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//The following was originally published in Naturephiles on [[ScienceFriday.com|http://www.sciencefriday.com/blogs/08/27/2012/a-warbler-rises-from-the-ashes.html?audience=2&series=2]].//
On a thin, sap-speckled branch of a jack pine, a male Kirtland’s warbler perches, its yellow chest puffed out and gleaming brilliantly under the sun. He poses proudly for a group of bird-watchers, whose eagerness to document this moment digitally sends their 400mm Canons and Nikons whirling in a shower of shutter clicks.
The sense of isolation that unfolds over the field of dry, brown grass, low shrubs, and stubby pines makes the excitement seem excessive at first. But this is the jack pine barrens of Michigan’s northern Lower Peninsula, the place where Kirtland's warblers (//Dendroica kirtlandii//) -- one of North America's rarest songbird species -- come to breed. Kirtland's warblers can be seen in the barrens only from late May until August or September, when they depart for their wintering grounds, more than 1,200 miles away in The Bahamas and nearby islands.
Down to just 167 singing males in 1987, the Kirtland's warbler population has rebounded, with 1,828 males counted in 2011. The species has risen, almost literally, like a phoenix from the ashes. The Kirtland's warbler builds its nest on top of sandy, well-drained soils and depends on shrubs to provide cover and food -- characteristics that in the barrens are made possible by fire. This association led to the warbler's nickname, the “bird of fire.”
The best breeding forests for Kirtland's warblers emerge about six years after a burn, when low shrubs, such as sweetfern, sand cherry, and blueberry, grow densely beneath and near young jack pines. By this time, the pines are at least five feet in height, and stands are separated by sprawling grassy openings.
Jack pine forests historically burned at regular intervals as a result of natural and human-associated factors. Native Americans, for instance, may have set fires intentionally in the barrens. But with the expansion of European settlement in the 19th and 20th centuries, fire suppression became the norm, and ecological succession suddenly was allowed to proceed in the barrens. As the forests grew up and the grasslands closed, the warblers' breeding habitat disappeared. And the warbler, too, began to disappear.
The Kirtland's warbler's survival was also endangered by the presence of brown-headed cowbirds (//Molothrus ater//). As their name suggests, cowbirds associate with cattle, and they presumably followed cattle, introduced by humans, into the Great Lakes region. Cowbirds, however, never build nests of their own. Instead, they lay their eggs in the nests of small birds like Kirtland's warblers and cause a reduction in host chick survival.
Fortunately, intense fire management and efforts to control cowbird nest parasitism in the jack pine barrens have paid off. There appear to be more Kirtland's warblers alive today than at any other time since the first specimen was collected in 1851 by Charles Pease. The species has extended its summer range, too, with nests found in places such as Wisconsin and north of the Lower Peninsula, into Ontario, Canada.
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Researchers in Australia have reported the discovery of a new species of dolphin, the [[Burrunan dolphin|Burrunan dolphin]] (//Tursiops australis//). Using a combination of mitochondrial DNA and microsatellite analysis and assessment of coloration and cranial characters, the team was able to conclude that a coastal dolphin endemic to south-eastern Australia was in fact different from the bottlenose species //Tursiops truncatus// and //Tursiops aduncus//.
The new species may already be endangered. According to the researchers, the Burrunan dolphin inhabits only a small region off southern and south-eastern Australia that lies close to a large urban and agricultural region on land. Furthermore, the dolphins are known from just two small resident populations.
For more information, see:
[[A New Dolphin Species, the Burrunan Dolphin Tursiops australis sp. nov., Endemic to Southern Australian Coastal Waters|http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0024047]]
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Welcome to Nature. Science. Life.
I am an author, freelance science writer, and editor based in Madison, Wisconsin, and a member of the National Association of Science Writers. This site provides information on my background in science and science writing.
For information about me and my writing experience, please visit [[The Writer]]. If you are interested in hiring me for a freelance writing project, please contact me via email (kerogers (at) nasw.org). Follow me on [[Twitter|http://twitter.com/#!/karaerogers]], too.
I am the author of //[[The Quiet Extinction: Stories of North America’s Rare and Threatened Plants|http://www.uapress.arizona.edu/Books/bid2541.htm]]// (University of Arizona Press, 2015) and //[[Out of Nature: Why Drugs From Plants Matter to the Future of Humanity|http://www.uapress.arizona.edu/Books/bid2350.htm]]// (University of Arizona Press, 2012).
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//Pygoscelis adeliae//
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!East Africa
!!Kenya
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!!Congo (Brazaville)
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//Fulica americana//
[img[Images/coot_small.JPG]]
Photo credit: J.D. Rogers
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The American pika (//Ochotona princeps//) was the second species petitioned for protection under the U.S. Endangered Species Act (ESA) because of threats posed by climate change (the polar bear was the first). In 2010, however, the U.S. Fish and Wildlife Service elected not to protect the American pika under the ESA, despite evidence of declines in pika populations linked to local climate change.
The American pika is a rodent-sized mammal that weighs between 4.5 and 7 ounces. It has round ears and is brown and gray in color. Although it looks an awful lot like a rodent, it is actually related to lagomorphs (hares and rabbits; family Leporidae). Pikas favor talus slopes in the mountains of the western United States, including in the Sierra Nevada, the Cascade Range, and the northern and southern Rocky Mountains. It is most often found at elevations between 8,000 and 13,000 feet, though in some areas it may be found at much lower elevations.
Pikas living at low-elevation sites are highly susceptible to local climate change, including warming and drying. They often cannot withstand prolonged exposure to temperatures above 75 to 78 °F.
For more, see: [[Pint-Sized Pika Challenged by Climate Change]].
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The apple tree (//Malus domestica//), the source of the beloved "orchard," "table," or simply "domestic" apple, is a descendent of the wild apple, //Malus sieversii//, which is native to mountainous areas of Central Asia. //M. domestica// emerged in Western Asia and is believed to have been one of the first cultivated trees in the world. There are now more than 7,500 cultivars worldwide, with China and the United States being the world's leading apple producers.
The apple genome contains some 57,000 genes (for comparison, the human genome consists of some 20,000 to 25,000 genes). Knowledge of the genome of the domestic apple could lead to the development of new approaches to prevent diseases affecting apple trees and techniques to further shape the size and taste of apples.
Throughout history, the apple has held a significant place in human culture. Perhaps most famous is the perception of the apple as the forbidden fruit. Indeed, the apple is believed to have been portrayed as a forbidden fruit in Greek mythology, and many suspect that the apple is in fact the forbidden fruit mentioned in the Book of Genesis.
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//Arctogadus glacialis//
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The Arctic fox (//Alopex lagopus//) is known for its fluffy white or bluish coat, small size, and remarkable hardiness. The fox's native habitat is the unforgiving tundra, where, during the winter, it endures temperatures that dip to more than 50° below freezing (Celsius). In the summer, its bright white coat turns brown or grey, enabling it to remain camouflaged with its surroundings. The Arctic fox is an omnivore. It eats plants, hunts small animals such as rodents, and scavenges on the remains of animals killed by predators such as polar bears.
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!East Asia
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Assassin bugs are aggressive insects with sharp, segmented beaks, which they use to suck the blood—and life—from unsuspecting victims.
[[Research published|http://heteroptera.ucr.edu/index.php?option=com_content&task=view&id=32&Itemid=51]] in 2011 the journal //Animal Behavior// revealed the extent of the bugs' true assassin nature. Waiting for a rustling of wind to drown out the sound of its movement, the assassin //Stenolemus bituberus// stalks its spider victims on their webs, taking advantage of web-building spiders' poor eyesight. The assassin inches closer and closer until suddenly it stabs its victim with its beak, killing the spider instantly.
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A 2009 report by the International Commission for the Conservation of Atlantic Tunas (ICCAT) indicated that Atlantic bluefin tuna stocks are 15 percent below their original size. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has created a proposal to ban international trade in Atlantic bluefin tuna. The proposal will be reviewed in March 2010 and would prevent trade temporarily to allow bluefin stocks to recover.
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//Fratercula arctica//
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The autumn crocus (//Colchicum autumnale// L.), also known as naked lady or meadow saffron, is a member of the Liliaceae family. It is a perennial herb that typically blooms in the fall (hence its common name). It is native to Eurasia and northern parts of Africa.
The autumn crocus is perhaps best known for its toxicity. Indeed, all parts of the plant are poisonous, though the seeds and corms are especially dangerous. These parts contain high concentrations of the alkaloid colchicine, a compound that inhibits cell division. A compound known as """ICT2588""", a derivative of colchicine, [[has been shown|http://www.nhs.uk/news/2011/09September/Pages/crocus-drug-studied-cancer-treatment.aspx]] to be effective against fibrosarcomas in mice. The compound is under investigation for its use in the treatment of human cancer.
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The Bengal tiger (//Panthera tigris tigris//), native to Bangladesh, India, China, Siberia, and Indonesia, is an iconic species known especially for its appearance, being orange with black stripes and white underside, chest, and eyebrows. The Bengal tiger is the most numerous of the remaining tiger species. Yet, there remain only 2,100 to 2,500 in the wild, and hence it is listed as endangered. Bengal tigers weigh between 300 and 500 pounds (females are lighter than males) and are ferocious predators, hunting large hoofed herbivorous quadrupeds such as gaur, water buffalo, and chital deer, as well as smaller animals such as hares.
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The bird-of-paradise flower (//Strelitzia reginae//) is native to South Africa and produces a remarkable orange and purplish-blue flower that resembles a bird, at the top of a long stalk. To learn more about this beautiful plant, read [[The Exotic Bird-of-Paradise Flower]].
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A study of the [[Somalian cavefish|Somalian cavefish]] //Phreatichthys andruzzii// has provided new insight into the role of light in maintaining circadian rhythm. //P. andruzzii// was found to have a 47-hour infradian rhythm (a circadian rhythm greater than 28 hours) that is influenced not by light but by food. When zebrafish, which have typical, light-sensitive, roughly 24-hour circadian rhythms, were fed at the same time each day for about a month, researchers found that "clock" genes associated with food became active, indicating that both light and food, not just light alone, were responsible for maintaining the fishes' internal clocks. In addition, the researchers discovered two new non-visual photoreceptors that are capable of influencing circadian rhythm.
For more information, see:
#[[A Blind Circadian Clock in Cavefish Reveals that Opsins Mediate Peripheral Clock Photoreception|http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001142]]
#[[Light-Insensitive Cavefish Provide Insight into Circadian Rhythm|http://www.talkingscience.org/2011/09/light-insensitive-cavefish-provide-insight-into-circadian-rhythm/]]
#//[[Phreatichthys andruzzii|http://www.iucnredlist.org/apps/redlist/details/40703/0]]//
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Blue whales (//Balaenoptera musculus//) are among the largest animals known, reaching lengths of up to 100 feet and weighing more than 100 tons. Some females can weigh as much as 150 tons! Blue whales found in the Southern Hemisphere tend to be larger than those occurring in the Northern Hemisphere. Like all other mammals, blue whales raise their young on milk, and they have lungs rather than gills.
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The bristlecone pine (//Pinus longaeva//) is a fascinating member of the pine family (Pinaceae) known for its often contorted appearance and its longevity. The oldest known bristlecone pine is an estimated 5,000 years old. These trees are native to the southwest region of the United States and Rocky Mountains. They are listed as vulnerable on the [[IUCN Red List of Threatened Species|http://www.iucnredlist.org/]].
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The bumblebee bat (//Craseonycteris thonglongyai//), also known as the hog nosed bat, Old World hog nosed bat, or Kitti's hog nosed bat, is one of the world's smallest mammals, weighing about two grams and measuring just over one inch in length. In addition to its small size, the bumblebee bat is also known its fleshy snout resembling that of a pig's. It is red-brown to gray in color and forages for insects just after sunset and just before sunrise.
The bumblebee bat's range extends from southern Myanmar to west-central Thailand. Many individuals appear to take refuge in limestone caves along rivers deep in the forests of Sai Yok National Park. The species has been in decline since the 1970s. Between 1983 and 1997, populations declined by an estimated 10 percent and between 1998 and 2008 by an estimated 14 percent. Fewer than 10,000 bumblebee bats are thought to exist in the wild today; a decline of another 10 percent is expected to occur in Thailand in the next decade.
For more, see:
[[The Flight of the Bumblebee Bat]]
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The Burrunan dolphin (//Tursiops australis//) is a coastal species that is endemic to a small region off southern and southeastern Australia. It is known from two small resident populations in that region. It is distinguished from the bottlenose dolphins //Tursiops truncatus// and //Tursiops aduncus// by physical features, such as its coloration and cranial structure, as well as by genetic features. The species was discovered in 2011 and may be endangered.
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//C. elegans// is a nematode (or roundworm) classified in the family Rhabditidae. It inhabits moist soil and is sometimes found on rotting vegetation. It is unsegmented, transparent, and grows to a length of approximately 1 mm. //C. elegans// typically is hermaphroditic and self-fertilizing; females do not occur naturally and males occur only very rarely.
//C. elegans// has a simple brain and nervous system that enables it to process sensory information. Hence, it senses and responds to chemical, temperature, and mechanical (e.g., touch, pressure) changes in its environment. These senses play a vital role in //C. elegans//' behavior and survival. Chemoreception, for example, enables the detection of food and potential mates (when males are present). //C. elegans// does not rely on vision, presumably because it evolved in and inhabits dark environments.
//C. elegans// possesses several key traits that make it ideal for scientific research. These traits include its transparent body (making its body structure readily observable under a microscope), its rapid rate of reproduction, its simple nervous system, and its genome. //C. elegans//' genome consists of about 20,000 genes, 40 to 50 percent of which are homologous to human genes.
Scientists have learned a great deal of information from their studies of //C. elegans//. Perhaps one of the most interesting areas of research involving the species is in the realm of space.
For more, see: [[Space Worms and the Biological Impact of Long-Duration Spaceflight]].
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The camphor tree (//Cinnamomum camphora//), a member of the laurel family (Lauraceae), is found in India, China, and parts of Southeast Asia. An aromatic waxy substance known as camphor that is produced by the tree and produces a cooling effect on the skin is used as a mild topical anesthetic.
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!Barbados
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//This post was originally published in my column [[NaturePhiles|http://www.talkingscience.org/category/naturephiles/]] on [[Talking Science|http://www.talkingscience.org/2012/02/chevrotains-and-the-world-of-unusual-tiny-ungulates/]].//
In the dense undergrowth of the tropical forests of Southeast Asia lives the world’s smallest hoofed mammal, the lesser Malay chevrotain (//Tragulus kanchil//). Weighing around 2 kg (4.4 pounds) and measuring about 50 cm (1.6 feet) in length, the little arched-back creature teeters along on delicate, stilt-like legs, dwarfed by the oversized jungle vegetation.
The lesser Malay is one of 10 living species of chevrotains, which are also known as mouse deer, because of their small size and deer-like appearance. And similar to deer, chevrotains have two-toed hooves and specialized stomachs that allow them to regurgitate and chew on partially digested plant matter to help breakdown undigestible cellulose -- characteristics that classify them as ruminants. Chevrotains, however, are the most primitive ruminants alive today, as evidenced by their lack of horns or antlers, their long upper canine teeth, and their three-chambered stomachs (as opposed to the typical four-chambered anatomy of other ruminants). These features, along with certain pig-like characteristics, have led some scientists to conclude that chevrotains form an evolutionary link between ruminants and nonruminants, or animals with single-chambered stomachs, such as pigs and humans.
[Img[Images/Lesser_malay_chevrotain.jpg]]
The lesser Malay chevrotain (//Tragulus kanchil//). Photo credit: Linda Kenney
But while information about the physical traits of chevrotains is available, knowledge of their behavior is lacking, in large part because of their secretive nature. For example, it was long thought that the lesser Malay chevrotain was nocturnal, but [[a radiotracking study|http://www.asmjournals.org/doi/abs/10.1644/1545-1542%282003%29084%3C0234%3AAAHUOL%3E2.0.CO%3B2]] published in 2003 that was conducted at the ~Kabili-Sepilok Forest Reserve on the island of Borneo described daytime foraging and nighttime resting, suggesting that the species is not nocturnal. That same study also revealed that lesser chevrotains in the reserve tended to spend early and late daylight hours in areas where gaps in the forest canopy permitted dense growth of climbing bamboo (Dinochloa), which presumably offered cover from predators when foraging for fruit and leaves. With the onset of darkness, the animals moved to elevated ridge areas to rest.
The lesser Malay chevrotain is one of six species in the genus //Tragulus//. Several of these species are readily distinguished by their size, geographical range, or coat coloration; others, however, are so similar in appearance that scientists can tell them apart only through careful analysis of cranial features. Such analyses have led to the division of the six species into 24 subspecies.
[Img[Images/Java_mouse_deer.jpg]]
The Java mouse deer (//Tragulus javanicus//). Photo credit: Levg
Other chevrotains include the Indian, yellow-striped, and white-spotted chevrotains of the genus //Moschiola// and the water chevrotain of the genus //Hyemoschus//. The Indian chevrotain typically is found on rocky, grassy hillsides or near streams in tropical deciduous and evergreen forests throughout much of India. The yellow-striped and white-spotted chevrotains, on the other hand, are found only in Sri Lanka, with the former inhabiting the wet, southwestern region and the latter the dry region that characterizes the east, west, and north of the country. All members of //Moschiola// are thought to be nocturnal and feed on shrubs, herbs, and fruit.
The water chevrotain (//Hyemoschus aquaticus//) is perhaps the best characterized and most unusual of the group, known for its tendency to dive underwater to escape predators. However, with its round, rodent-like body, spindly legs, and hoofed feet, it is an inefficient swimmer and tires quickly as it paddles along. Compared with other chevrotains, the water chevrotain is large, weighing 7 to 16 kg (15 to 35 pounds) and standing about 30 to 40 cm (1 to 1.3 feet) at the shoulder. It’s reddish-brown coat has dull white streaks and spots, which may help it to blend in with the dense cover of the tropical forests that characterize its native habitat in western and central Africa.
At least four species of chevrotains, including the water chevrotain, the silver-back chevrotain (//T. versicolor//), Williamson’s chevrotain (//T. williamsoni//), and the larger Malay chevrotain (//T. napu//), are decreasing in number. In addition, the Balabac chevrotain (//T. nigricans//), which inhabits the tiny island of the same name in the far southwestern Philippines, is endangered. However, because there is insufficient data on the actual population status of these species, and because national and local laws have not been enforced in the Philippines, little has been done to protect these amazing animals.
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//This post was originally published in my column [[NaturePhiles|http://www.talkingscience.org/category/naturephiles/]] on [[TalkingScience.org|http://www.talkingscience.org/2011/12/climate-humans-and-extinction-lessons-from-the-past/]].//
Around 20,000 years ago, as the Last Glacial Maximum—the world's last significant glacial period—was coming to a close, Earth began to change dramatically. The climate warmed, large ice sheets began to melt, and humans crept increasingly into northern latitudes. At the same time, large mammals, or megafauna, such as woolly mammoths, woolly rhinoceros, and cave lions, were disappearing. In the end, North America lost 72 percent of its megafauna, and Eurasia 36 percent.
[img[Images/Woolly_rhinoceros.jpg]]
A woolly rhinoceros (source: Henry Fairfield Osborn, //Men of the old stone age// 1915, illustrated by Charles R. Knight).
Climate change and humans appear to have served as the driving factors behind megafaunal extinction at the end of the Late Quaternary period (which began around 50,000 years ago). According to [[a study|http://www.nature.com/nature/journal/v479/n7373/full/nature10574.html]] published recently in the journal //Nature//, however, different species responded in different ways to climate and humans. For example, whereas climate change was a major factor in the downfall of the woolly rhinoceros and Eurasion musk ox, a combination of climate and human activity led to the demise of the Eurasian steppe bison. The findings are significant because they help dissipate some of the contention surrounding the specific roles of climate and humans in the context of this historical extinction episode. Perhaps more importantly, however, they highlight the challenges that lie ahead for scientists who are working to identify extant species that are at risk of extinction from climate change and human activity in the modern era.
To identify the specific contributions of climate and humans to megafaunal extinction, the scientists of the //Nature// study analyzed the demographic histories of six extinct or extant Late Quaternary megafauna herbivores of Eurasia and North America. The species included woolly mammoth (//Mammuthus primigenius//), woolly rhinoceros (//Coelodonta antiquitatis//), reindeer (//Rangifer tarandus//), musk ox (//Ovibus moschatus//), bison and Eurasion steppe bison (//Bison bison// and //B. priscus//), and wild and domestic horse (//Equus ferus// and //E. caballus//).
The scientists also determined the age of megafaunal remains using radiocarbon dating and investigated each species' genetic signature using mitochondrial DNA isolated from bone samples. From their analyses, they were able to determine past species distributions and the geographical overlap of each species with humans at the end of the Late Quaternary.
After the Last Glacial Maximum (LGM), the world's ice sheets began to retreat and climatic shifts forced habitat redistribution. For the woolly rhinoceros in Siberia, which had relatively little regional overlap with Paleolithic humans and was found in less than 11 percent of Siberian archaeological sites dating to the period after the LGM, climate likely was the predominant driver of extinction. A similar conclusion was reached for musk ox in Eurasia.
Wild horses, on the other hand, had a large geographical distribution, indicative of a large population, in Eurasia until about 6,000 years ago, which is inconsistent with climate-driven extinction during this time. Subsequent declines in the genetic diversity of the wild horse after the LGM, however, are coincident with human expansion in Europe and Asia, indicating that humans, likely through selective hunting, were responsible for the species' decline. Declines in bison and reindeer observed well after the LGM also reflect the impact of expanding human populations at that time.
The only species for which no conclusion could be reached regarding the cause of extinction was the woolly mammoth. Although archaeological evidence suggests geographical overlap between humans and woolly mammoth in Eurasia, Siberia, and North America, Siberian sites containing woolly mammoth remains decline markedly after the LGM, a phenomenon that could have been the result of human or climatic factors.
Evidence that shifts in habitat distribution were linked with species population size at the end of the Late Quaternary reinforces the significance of the relationship between habitat loss and the future of species alive today. Stemming the loss of habitat from climate change and human activities, particularly development and agriculture, is one of the greatest challenges now facing conservation.
Back to [[The Nature Beat|The Nature Beat]]
See also [[Eurasia|Eurasia]]
See also [[The Americas|The Americas]]
<<tiddler HideTiddlerTags>>
Back to [[Major Seas|Major Seas]]
Back to [[Bodies of Water|Bodies of Water]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Climate change and rapidly increasing levels of greenhouse gases are threatening the survival of the world's corals, which are key elements of ocean ecosystems. Scientists, concerned that corals are dying too quickly to be saved, have proposed freezing corals as a way to preserve samples for the future.
Back to [[Nature]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<list filter [tag[Coral]]>>
Back to [[In the Water|In the Water]]
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Back to [[The Nature Beat|The Nature Beat]]
[[Elusive Snails|http://sciencefriday.com/blogs/08/14/2012/elusive-snails.html?audience=2&series=2]]
[[The Fabled Jackdaw|http://sciencefriday.com/blogs/08/20/2012/the-fabled-jackdaw.html?audience=2&series=2]]
[[A Warbler Rises from the Ashes|http://sciencefriday.com/blogs/08/27/2012/a-warbler-rises-from-the-ashes.html?audience=2&series=2]]
[[Delmarva Peninsula's Endangered Squirrel |http://sciencefriday.com/blogs/09/04/2012/delmarva-peninsula-s-endangered-squirrel.html?audience=2&series=2]]
[[Foresight in the Arctic: Predation and Preservation|http://sciencefriday.com/blogs/09/10/2012/foresight-in-the-arctic-predation-and-preservation.html?audience=2&series=2]]
[[Children and Nature: The Need for Safe Places of Exploration|http://sciencefriday.com/blogs/09/17/2012/children-and-nature-the-need-for-safe-places-of-exploration.html?audience=2&series=2]]
[[Tiny Invasive Insect Rewrites the Landscape|http://sciencefriday.com/blogs/09/24/2012/tiny-invasive-insect-rewrites-the-landscape.html?series=2]]
<<tiddler HideTiddlerTags>>
<<list filter [tag[Eurasia1]]>>
Back to [[Species by Region|Species by Region]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
//Haematopus ostralegus//
[img[Images/oystercatcher_eurasian_small.jpg]]
Photo credit: J.D. Rogers
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
!East Europe
!!Russia
!North Europe
!!Channel Islands
!!Iceland
!South Europe
!West Europe
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
The European rabbit (//Oryctolagus cuniculus//) is native to the western Mediterranean and to northwestern Africa. It is a [[keystone species on the Iberian Peninsula|http://onlinelibrary.wiley.com/doi/10.1111/j.1523-1739.2008.00993.x/abstract;jsessionid=B2C54A9CD69095D7EDCBBE18061BD7FC.d03t01]] (Spain and Portugal), where it maintains open habitat and plant diversity through its grazing and foraging behavior. It is also an important source of prey for the Spanish Imperial eagle (//Aquila adalberti//), the Iberian lynx (//Lynx pardinus//), and other predators. The decline of European rabbit populations within the peninsula, however, [[has led to corresponding declines|http://www.iucnredlist.org/news/rabbits-at-risk-home-range]] in eagle and lynx populations.
Scientists [[reported in 2000|http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CB8QFjAA&url=http%3A%2F%2Fwww.carnivoreconservation.org%2Ffiles%2Factionplans%2Fcoe%2FSN111-E.pdf&ei=7RBnUK3LKYWryQGI_oCwDw&usg=AFQjCNEtk7JWxWC_-YpLSB1r0Bp6Nvqr9Q]] that some European rabbit populations in southwestern Spain (in Doñana National Park) had decreased by 95 percent since the 1950s. The primary cause was the arrival of two nonnative viral diseases: myxomatosis (introduced in France in 1952) and rabbit hemorrhagic disease (introduced to the Iberian Peninsula in the late 1980s). The loss of habitat, pest eradication, and hunting on the peninsula [[have also played a role|http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CB8QFjAA&url=http%3A%2F%2Fwww.ualberta.ca%2F~dhik%2Flsg%2Freport_lynx_rabit.pdf&ei=exZnUIGcNaavygGgmoH4CQ&usg=AFQjCNH2Jr1-pXasBzAFXmR0ikRKMzWp9A]] in its decline.
Outside of the Iberian Peninsula and the northwestern edge of Africa, the European rabbit has a notorious reputation as an invasive species. The species can now be found worldwide (except Antarctica). Its devastation to native flora and fauna in Australia, where in 1788 it arrived as a captive animal but in 1859 was released into the wild, has formed the basis for a variety of studies concerned with understanding the ecological impact of invasive species.
In Australia, the European rabbit is thought to have facilitated the extinction of at least several native species, particularly small mammals, with which it competes for habitat and food resources. Furthermore, the rabbit's populations are capable of explosive growth in certain years, enabling the species to quickly overtake more slowly reproducing native animals. Its impact on the greater bilby (//Macrotis lagotis//) in particular has become increasingly conspicuous, given the bilby's popularity among locals. In many areas beyond its native range, the European rabbit may cause economically significant damage to crops such as oats and wheat.
Despite its great numbers in places where it is invasive, the International Union for the Conservation of Nature (IUCN) has [[listed the European rabbit as near threatened|http://www.iucnredlist.org/details/full/41291/0]], since its populations remain significantly reduced on the Iberian Peninsula.
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
//Spizella pusilla//
[img[Images/FieldSparrow1_small.JPG]]
Photo credit: J.D. Rogers
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
The rare Fiji petrel (//Pseudobulweria macgillivrayi//) was sighted off Gau Island in May 2009. The sighting was the first confirmed at sea since the first specimen of the species was found in 1855 on Gau.
For more information, see:
#[[First observations of Fiji petrel Pseudobulweria macgillivrayi at sea: off Gau Island, Fiji, in May 2009.|http://www.boc-online.org/bulletins/downloads/Pseudobulweria%20macgillivrayi%20Shirihai%20et%20al.pdf]]
#[['Lost seabird' returns to ocean.|http://news.bbc.co.uk/earth/hi/earth_news/newsid_8250000/8250215.stm]]
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
<<list filter [tag[Fishes1]]>>
Back to [[In the Water|In the Water]]
Back to [[Map|Map]]
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
<<list filter [tag[Frog]]>>
Back to [[Tiny Life|Tiny Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
[[North America]]
[[Central America]]
[[South America]]
[[Caribbean]]
[[Europe]]
[[Africa]]
[[Asia]]
[[Oceania]]
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
!!!First, you will need to save this file to your local harddrive to edit. [[Right click and save as|tw_website_template_jdr.html]] to download this page for customization. Then open the saved version in a browser. After modifying, you can upload this file to a webserver to host your own site.
!!!To make this more suitable as a website, the following changes were made to the default [[empty|empty.html]] ~TiddlyWiki:
# Imported HideTiddlerTags, HideTiddlerSubtitle, HideTiddlerToolbar, ReplaceDoubleClick, SinglePageModePlugin, ToggleRightSidebar, InlineJavascriptPlugin from http://www.tiddlytools.com
# Created an [[Example]] tiddler showing how to hide toolbars, tags, and subtitle.
# Created a zzConfigTweaks tiddler to make the default options stick and tagged it with systemConfig tag so it loads
# Added the rightsidebar toggle dot to the subtitle
# Added {{{<span macro="tiddler ReplaceDoubleClick with: shift doubleclick"></span>}}} to the ViewTemplate
# Added these notes to the GettingStarted tiddler
!!!With the above changes, by default the rightsidebar is hidden. You can toggle it by clicking the period at the end of the subtitle. To edit a tiddler, you hold shift and double click the tiddler title. If you edit the [[Example]] tiddler, you can see the last three lines that hide the parts of a tiddler to make it look cleaner for a website.
To start customizing this blank TiddlyWiki, modify the following tiddlers:
* SiteTitle & SiteSubtitle: The title and subtitle of the site, as shown above (after saving, they will also appear in the browser title bar)
* MainMenu: The menu (usually on the left)
* DefaultTiddlers: Contains the names of the tiddlers that you want to appear when the TiddlyWiki is opened
You'll also need to enter your username for signing your edits: <<option txtUserName>>
The giraffe (//Giraffa camelopardalis//) is the tallest land mammal on Earth. In addition to its height, it is distinguished by its unusually long neck, its patchy brown coat, and its stubby horns. Giraffes are found primarily in East Africa.
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
The gray wolf (//Canis lupus//) is a member of the dog family (Canidae) and is perhaps best known for its extirpation from and reintroduction into the United States. It is thought that perhaps as many as 2 million gray wolves once roamed the planet, but today there are about 200,000, spread between Canada, the United States, and Eurasia. Many packs were killed off by human hunters.
A full-grown male may measure 2.5 feet at shoulder height, measure 4.5 to 6.5 feet in length from the nose to the tip of the tail, and weigh between 55 and 130 pounds. Males weighing more than 140 pounds have been found in the interior of Yellowstone National Park. They prey on elk, [[pronghorn|Pronghorn]], deer, [[moose|Moose]], bison, and caribou, typically chasing after weak or small individuals. They also eat smaller animals, such as rabbits, hares, and beavers.
Wolves have an amazingly complex social structure that is based on a highly organized hierarchy. An alpha male and an alpha female reside at the top of the hierarchy; their role involves leading the pack and determining the hierarchical rankings of others within the pack, all of whom are descendants of the alphas. Below the alphas are the betas, which reinforce the dominant position of the alphas and the subordinate positions of those in lesser ranks. An omega wolf forms the base of the hierarchy. Behaviors such as ritualistic fighting and submissive posturing are used to reinforce a wolf's position in the pecking order.
Some of the most famous wolf packs reside in Yellowstone, where the gray wolf was reintroduced in 1995. Since its reintroduction, however, the wolf has been the center of controversy. The extirpation of wolves from Wyoming changed Yellowstone's ecosystem by initiating a gradual collapse marked by the lack of growth of aspen saplings due to overgrazing primarily by elk. After reintroduction, the ecosystem began to rebound, aspen saplings began to grow and the size of overgrown elk herds was reduced. But many view the wolf as an enemy and claim that wolves outside Yellowstone's boundaries kill too many livestock. (Wolves actually claim far fewer livestock annually than other predators, such as coyotes; see [[here|http://www.nass.usda.gov/Statistics_by_State/Montana/Publications/livestock/sh_llos3.htm]].)
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Back to [[Major Seas|Major Seas]]
Back to [[Bodies of Water|Bodies of Water]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Back to [[Major Seas|Major Seas]]
Back to [[Bodies of Water|Bodies of Water]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<closeAll>><<permaview>><<newTiddler>><<newJournal 'DD MMM YYYY'>><<saveChanges>><<slider chkSliderOptionsPanel OptionsPanel 'options »' 'Change TiddlyWiki advanced options'>>
There are more than 55 species of Hawaiian honeycreepers, although today only about 18 or 19 species are extant. These songbirds are known variously for their bright coloration, bill shape, and unique behavior. Honeycreepers also serve as a remarkable example of adaptive radiation, the evolution of a group into diverse forms, each of which fulfills a unique ecological role.
Of the remaining species of honeycreepers, most are listed as endangered or critically endangered, due to disease (namely avian pox and avian malaria), habitat loss, predation by invasive predators, and competition with invasive birds. These factors, all of which came about following captain James Cook's discovery of the Hawaiian Islands in 1778, have caused the loss of more than a third of honeycreeper species. Another third had been lost between the time when humans first arrived on the islands, around 300 CE, and Cook's discovery.
For more, see: [[Trouble in Paradise: Mosquitoes, Disease, and Hawaii’s Native Forest Birds]].
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
/%
|Name|HideTiddlerSubtitle|
|Source|http://www.TiddlyTools.com/#HideTiddlerSubtitle|
|Version|0.0.0|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|script|
|Requires|InlineJavascriptPlugin|
|Overrides||
|Description|hide a tiddler's subtitle (dates/created by) display|
Usage: <<tiddler HideTiddlerSubtitle>>
%/<script>
var t=story.findContainingTiddler(place);
if (!t || t.id=="tiddlerHideTiddlerSubtitle") return;
var nodes=t.getElementsByTagName("*");
for (var i=0; i<nodes.length; i++)
if (hasClass(nodes[i],"subtitle"))
nodes[i].style.display="none";
</script>
/%
|Name|HideTiddlerTags|
|Source|http://www.TiddlyTools.com/#HideTiddlerTags|
|Version|0.0.0|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|script|
|Requires|InlineJavascriptPlugin|
|Overrides||
|Description|hide a tiddler's tagged/tagging display elements|
Usage: <<tiddler HideTiddlerTags>>
%/<script>
var t=story.findContainingTiddler(place);
if (!t || t.id=="tiddlerHideTiddlerTags") return;
var nodes=t.getElementsByTagName("div");
for (var i=0; i<nodes.length; i++)
if (hasClass(nodes[i],"tagged"))
nodes[i].style.display="none";
</script>
/%
|Name|HideTiddlerToolbar|
|Source|http://www.TiddlyTools.com/#HideTiddlerToolbar|
|Version|0.0.0|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|script|
|Requires|InlineJavascriptPlugin|
|Overrides||
|Description|hide a tiddler's toolbar display|
Usage: <<tiddler HideTiddlerToolbar>>
%/<script>
var t=story.findContainingTiddler(place);
if (!t || t.id=="tiddlerHideTiddlerToolbar") return;
var nodes=t.getElementsByTagName("*");
for (var i=0; i<nodes.length; i++)
if (hasClass(nodes[i],"toolbar"))
nodes[i].style.display="none";
</script>
The humpback whale (//Megaptera novaeangliae//) is among the world's most celebrated whales. It is found along the coasts of all oceans and is known for its large size, measuring as many as 14 meters in length and weighing 30–40 tons). It also performs remarkable migrations, traveling more than 8,000 km each year as it moves between its feeding and breeding habitats.
I was fortunate enough to interview University of Canterbury researcher Travis W. Horton, who in 2011 reported new insight into the humpback's remarkable migratory journey. That interview was published on the Britannica Blog, in [[In the Wake of the Humpback: Tracking Whale Migration (Science Up Front)|http://www.britannica.com/blogs/2011/08/wake-humpback-tracking-whale-migration-science-front/]].
Back to [[Life]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
[[Corals]]
[[Fishes]]
[[Marine Mammals]]
[[Oceans]]
[[Major Seas]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<list filter [tag[Indian]]>>
Back to [[Map|Map]]
Back to [[Oceans|Oceans]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
/***
|Name|InlineJavascriptPlugin|
|Source|http://www.TiddlyTools.com/#InlineJavascriptPlugin|
|Documentation|http://www.TiddlyTools.com/#InlineJavascriptPluginInfo|
|Version|1.9.4|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|plugin|
|Requires||
|Overrides||
|Description|Insert Javascript executable code directly into your tiddler content.|
''Call directly into TW core utility routines, define new functions, calculate values, add dynamically-generated TiddlyWiki-formatted output'' into tiddler content, or perform any other programmatic actions each time the tiddler is rendered.
!!!!!Documentation
>see [[InlineJavascriptPluginInfo]]
!!!!!Revisions
<<<
2009.02.26 [1.9.4] in $(), handle leading '#' on ID for compatibility with JQuery syntax
|please see [[InlineJavascriptPluginInfo]] for additional revision details|
2005.11.08 [1.0.0] initial release
<<<
!!!!!Code
***/
//{{{
version.extensions.InlineJavascriptPlugin= {major: 1, minor: 9, revision: 3, date: new Date(2008,6,11)};
config.formatters.push( {
name: "inlineJavascript",
match: "\\<script",
lookahead: "\\<script(?: src=\\\"((?:.|\\n)*?)\\\")?(?: label=\\\"((?:.|\\n)*?)\\\")?(?: title=\\\"((?:.|\\n)*?)\\\")?(?: key=\\\"((?:.|\\n)*?)\\\")?( show)?\\>((?:.|\\n)*?)\\</script\\>",
handler: function(w) {
var lookaheadRegExp = new RegExp(this.lookahead,"mg");
lookaheadRegExp.lastIndex = w.matchStart;
var lookaheadMatch = lookaheadRegExp.exec(w.source)
if(lookaheadMatch && lookaheadMatch.index == w.matchStart) {
var src=lookaheadMatch[1];
var label=lookaheadMatch[2];
var tip=lookaheadMatch[3];
var key=lookaheadMatch[4];
var show=lookaheadMatch[5];
var code=lookaheadMatch[6];
if (src) { // load a script library
// make script tag, set src, add to body to execute, then remove for cleanup
var script = document.createElement("script"); script.src = src;
document.body.appendChild(script); document.body.removeChild(script);
}
if (code) { // there is script code
if (show) // show inline script code in tiddler output
wikify("{{{\n"+lookaheadMatch[0]+"\n}}}\n",w.output);
if (label) { // create a link to an 'onclick' script
// add a link, define click handler, save code in link (pass 'place'), set link attributes
var link=createTiddlyElement(w.output,"a",null,"tiddlyLinkExisting",wikifyPlainText(label));
var fixup=code.replace(/document.write\s*\(/gi,'place.bufferedHTML+=(');
link.code="function _out(place){"+fixup+"\n};_out(this);"
link.tiddler=w.tiddler;
link.onclick=function(){
this.bufferedHTML="";
try{ var r=eval(this.code);
if(this.bufferedHTML.length || (typeof(r)==="string")&&r.length)
var s=this.parentNode.insertBefore(document.createElement("span"),this.nextSibling);
if(this.bufferedHTML.length)
s.innerHTML=this.bufferedHTML;
if((typeof(r)==="string")&&r.length) {
wikify(r,s,null,this.tiddler);
return false;
} else return r!==undefined?r:false;
} catch(e){alert(e.description||e.toString());return false;}
};
link.setAttribute("title",tip||"");
var URIcode='javascript:void(eval(decodeURIComponent(%22(function(){try{';
URIcode+=encodeURIComponent(encodeURIComponent(code.replace(/\n/g,' ')));
URIcode+='}catch(e){alert(e.description||e.toString())}})()%22)))';
link.setAttribute("href",URIcode);
link.style.cursor="pointer";
if (key) link.accessKey=key.substr(0,1); // single character only
}
else { // run inline script code
var fixup=code.replace(/document.write\s*\(/gi,'place.innerHTML+=(');
var c="function _out(place){"+fixup+"\n};_out(w.output);";
try { var out=eval(c); }
catch(e) { out=e.description?e.description:e.toString(); }
if (out && out.length) wikify(out,w.output,w.highlightRegExp,w.tiddler);
}
}
w.nextMatch = lookaheadMatch.index + lookaheadMatch[0].length;
}
}
} )
//}}}
// // Backward-compatibility for TW2.1.x and earlier
//{{{
if (typeof(wikifyPlainText)=="undefined") window.wikifyPlainText=function(text,limit,tiddler) {
if(limit > 0) text = text.substr(0,limit);
var wikifier = new Wikifier(text,formatter,null,tiddler);
return wikifier.wikifyPlain();
}
//}}}
// // GLOBAL FUNCTION: $(...) -- 'shorthand' convenience syntax for document.getElementById()
//{{{
if (typeof($)=='undefined') { function $(id) { return document.getElementById(id.replace(/^#/,'')); } }
//}}}
/***
|Name|InlineJavascriptPluginInfo|
|Source|http://www.TiddlyTools.com/#InlineJavascriptPlugin|
|Documentation|http://www.TiddlyTools.com/#InlineJavascriptPluginInfo|
|Version|1.9.6|
|Author|Eric Shulman|
|License|http://www.TiddlyTools.com/#LegalStatements|
|~CoreVersion|2.1|
|Type|documentation|
|Description|Documentation for InlineJavascriptPlugin|
''Call directly into TW core utility routines, define new functions, calculate values, add dynamically-generated TiddlyWiki-formatted output'' into tiddler content, or perform any other programmatic actions each time the tiddler is rendered.
!!!!!Usage
<<<
This plugin adds wiki syntax for surrounding tiddler content with {{{<script>}}} and {{{</script>}}} markers, so that it can be recognized as embedded javascript code. When a tiddler is rendered, the plugin automatically invokes any embedded scripts, which can be used to construct and return dynamically-generated output that is inserted into the tiddler content.
{{{
<script type="..." src="..." label="..." title="..." key="..." show>
/* javascript code goes here... */
</script>
}}}
All parameters are //optional//. When the ''show'' keyword is used, the plugin will also include the script source code in the output that it displays in the tiddler. This is helpful when creating examples for documentation purposes (such as used in this tiddler!)
__''Deferred execution from an 'onClick' link''__
<script label="click here" title="mouseover tooltip text" key="X" show>
/* javascript code goes here... */
alert('you clicked on the link!');
</script>
By including a {{{label="..."}}} parameter in the initial {{{<script>}}} marker, the plugin will create a link to an 'onclick' script that will only be executed when that specific link is clicked, rather than running the script each time the tiddler is rendered. You may also include a {{{title="..."}}} parameter to specify the 'tooltip' text that will appear whenever the mouse is moved over the onClick link text, and a {{{key="X"}}} parameter to specify an //access key// (which must be a //single// letter or numeric digit only).
__''Loading scripts from external source files''__
<script src="URL" show>
/* optional javascript code goes here... */
</script>You can also load javascript directly from an external source URL, by including a src="..." parameter in the initial {{{<script>}}} marker (e.g., {{{<script src="demo.js"></script>}}}). This is particularly useful when incorporating third-party javascript libraries for use in custom extensions and plugins. The 'foreign' javascript code remains isolated in a separate file that can be easily replaced whenever an updated library file becomes available.
In addition to loading the javascript from the external file, you can also use this feature to invoke javascript code contained within the {{{<script>...</script>}}} markers. This code is invoked //after// the external script file has been processed, and can make immediate use of the functions and/or global variables defined by the external script file.
>Note: To ensure that your javascript functions are always available when needed, you should load the libraries from a tiddler that is rendered as soon as your TiddlyWiki document is opened, such as MainMenu. For example: put your {{{<script src="..."></script>}}} syntax into a separate 'library' tiddler (e.g., LoadScripts), and then add {{{<<tiddler LoadScripts>>}}} to MainMenu so that the library is loaded before any other tiddlers that rely upon the functions it defines.
>
>Normally, loading external javascript in this way does not produce any direct output, and should not have any impact on the appearance of your MainMenu. However, if your LoadScripts tiddler contains notes or other visible content, you can suppress this output by using 'inline CSS' in the MainMenu, like this: {{{@@display:none;<<tiddler LoadScripts>>@@}}}
<<<
!!!!!Creating dynamic tiddler content and accessing the ~TiddlyWiki DOM
<<<
An important difference between TiddlyWiki inline scripting and conventional embedded javascript techniques for web pages is the method used to produce output that is dynamically inserted into the document: in a typical web document, you use the {{{document.write()}}} (or {{{document.writeln()}}}) function to output text sequences (often containing HTML tags) that are then rendered when the entire document is first loaded into the browser window.
However, in a ~TiddlyWiki document, tiddlers (and other DOM elements) are created, deleted, and rendered "on-the-fly", so writing directly to the global 'document' object does not produce the results you want (i.e., replacing the embedded script within the tiddler content), and instead will //completely replace the entire ~TiddlyWiki document in your browser window (which is clearly not a good thing!)//. In order to allow scripts to use {{{document.write()}}}, the plugin automatically converts and buffers all HTML output so it can be safely inserted into your tiddler content, immediately following the script.
''Note that {{{document.write()}}} can only be used to output "pure HTML" syntax. To produce //wiki-formatted// output, your script should instead return a text value containing the desired wiki-syntax content'', which will then be automatically rendered immediately following the script. If returning a text value is not sufficient for your needs, the plugin also provides an automatically-defined variable, 'place', that gives the script code ''direct access to the //containing DOM element//'' into which the tiddler output is being rendered. You can use this variable to ''perform direct DOM manipulations'' that can, for example:
* generate wiki-formatted output using {{{wikify("...content...",place)}}}
* vary the script's actions based upon the DOM element in which it is embedded
* access 'tiddler-relative' DOM information using {{{story.findContainingTiddler(place)}}}
Note:
''When using an 'onclick' script, the 'place' element actually refers to the onclick //link text// itself, instead of the containing DOM element.'' This permits you to directly reference or modify the link text to reflect any 'stateful' conditions that might set by the script. To refer to the containing DOM element from within an 'onclick' script, you can use "place.parentNode" instead.
<<<
!!!!!Instant "bookmarklets"
<<<
You can also use an 'onclick' link to define a "bookmarklet": a small piece of javascript that can be ''invoked directly from the browser without having to be defined within the current document.'' This allows you to create 'stand-alone' commands that can be applied to virtually ANY TiddlyWiki document... even remotely-hosted documents that have been written by others!! To create a bookmarklet, simply define an 'onclick' script and then grab the resulting link text and drag-and-drop it onto your browser's toolbar (or right-click and use the 'bookmark this link' command to add it to the browser's menu).
Notes:
*When writing scripts intended for use as bookmarklets, due to the ~URI-encoding required by the browser, ''you cannot not use ANY double-quotes (") within the bookmarklet script code.''
*All comments embedded in the bookmarklet script must ''use the fully-delimited {{{/* ... */}}} comment syntax,'' rather than the shorter {{{//}}} comment syntax.
*Most importantly, because bookmarklets are invoked directly from the browser interface and are not embedded within the TiddlyWiki document, there is NO containing 'place' DOM element surrounding the script. As a result, ''you cannot use a bookmarklet to generate dynamic output in your document,'' and using {{{document.write()}}} or returning wiki-syntax text or making reference to the 'place' DOM element will halt the script and report a "Reference Error" when that bookmarklet is invoked.
Please see [[InstantBookmarklets]] for many examples of 'onclick' scripts that can also be used as bookmarklets.
<<<
!!!!!Special reserved function name
<<<
The plugin 'wraps' all inline javascript code inside a function, {{{_out()}}}, so that any return value you provide can be correctly handled by the plugin and inserted into the tiddler. To avoid unpredictable results (and possibly fatal execution errors), this function should never be redefined or called from ''within'' your script code.
<<<
!!!!!$(...) 'shorthand' function
<<<
As described by Dustin Diaz [[here|http://www.dustindiaz.com/top-ten-javascript/]], the plugin defines a 'shorthand' function that allows you to write:
{{{
$(id)
}}}
in place of the normal standard javascript syntax:
{{{
document.getElementById(id)
}}}
This function is provided merely as a convenience for javascript coders that may be familiar with this abbreviation, in order to allow them to save a few bytes when writing their own inline script code.
<<<
!!!!!Examples
<<<
simple dynamic output:
><script show>
document.write("The current date/time is: "+(new Date())+"<br>");
return "link to current user: [["+config.options.txtUserName+"]]\n";
</script>
dynamic output using 'place' to get size information for current tiddler:
><script show>
if (!window.story) window.story=window;
var title=story.findContainingTiddler(place).getAttribute("tiddler");
var size=store.getTiddlerText(title).length;
return title+" is using "+size+" bytes";
</script>
dynamic output from an 'onclick' script, using {{{document.write()}}} and/or {{{return "..."}}}
><script label="click here" show>
document.write("<br>The current date/time is: "+(new Date())+"<br>");
return "link to current user: [["+config.options.txtUserName+"]]\n";
</script>
creating an 'onclick' button/link that accesses the link text AND the containing tiddler:
><script label="click here" title="clicking this link will show an 'alert' box" key="H" show>
if (!window.story) window.story=window;
var txt=place.firstChild.data;
var tid=story.findContainingTiddler(place).getAttribute('tiddler');
alert('Hello World!\nlinktext='+txt+'\ntiddler='+tid);
</script>
dynamically setting onclick link text based on stateful information:
>{{block{
{{{
<script label="click here">
/* toggle "txtSomething" value */
var on=(config.txtSomething=="ON");
place.innerHTML=on?"enable":"disable";
config.txtSomething=on?"OFF":"ON";
return "\nThe current value is: "+config.txtSomething;
</script><script>
/* initialize onclick link text based on current "txtSomething" value */
var on=(config.txtSomething=="ON");
place.lastChild.previousSibling.innerHTML=on?"disable":"enable";
</script>
}}}
<script label="click here">
/* toggle "txtSomething" value */
var on=(config.txtSomething=="ON");
place.innerHTML=on?"enable":"disable";
config.txtSomething=on?"OFF":"ON";
return "\nThe current value is: "+config.txtSomething;
</script><script>
/* initialize onclick link text based on current "txtSomething" value */
var on=(config.txtSomething=="ON");
place.lastChild.innerHTML=on?"enable":"disable";
</script>
}}}
loading a script from a source url:
>http://www.TiddlyTools.com/demo.js contains:
>>{{{function inlineJavascriptDemo() { alert('Hello from demo.js!!') } }}}
>>{{{displayMessage('InlineJavascriptPlugin: demo.js has been loaded');}}}
>note: When using this example on your local system, you will need to download the external script file from the above URL and install it into the same directory as your document.
>
><script src="demo.js" show>
return "inlineJavascriptDemo() function has been defined"
</script>
><script label="click to invoke inlineJavascriptDemo()" key="D" show>
inlineJavascriptDemo();
</script>
<<<
!!!!!Revisions
<<<
2010.12.15 1.9.6 allow (but ignore) type="..." syntax
2009.04.11 1.9.5 pass current tiddler object into wrapper code so it can be referenced from within 'onclick' scripts
2009.02.26 1.9.4 in $(), handle leading '#' on ID for compatibility with JQuery syntax
2008.06.11 1.9.3 added $(...) function as 'shorthand' for document.getElementById()
2008.03.03 1.9.2 corrected fallback declaration of wikifyPlainText() (fixes Safari "parse error")
2008.02.23 1.9.1 in onclick function, use string instead of array for 'bufferedHTML' (fixes IE errors)
2008.02.21 1.9.0 output from 'onclick' scripts (return value or document.write() calls) are now buffered and rendered into into a span following the script. Also, added default 'return false' handling if no return value provided (prevents HREF from being triggered -- return TRUE to allow HREF to be processed). Thanks to Xavier Verges for suggestion and preliminary code.
2008.02.14 1.8.1 added backward-compatibility for use of wikifyPlainText() in TW2.1.3 and earlier
2008.01.08 [*.*.*] plugin size reduction: documentation moved to ...Info tiddler
2007.12.28 1.8.0 added support for key="X" syntax to specify custom access key definitions
2007.12.15 1.7.0 autogenerate URI encoded HREF on links for onclick scripts. Drag links to browser toolbar to create bookmarklets. IMPORTANT NOTE: place is NOT defined when scripts are used as bookmarklets. In addition, double-quotes will cause syntax errors. Thanks to PaulReiber for debugging and brainstorming.
2007.11.26 1.6.2 when converting "document.write()" function calls in inline code, allow whitespace between "write" and "(" so that "document.write ( foobar )" is properly converted.
2007.11.16 1.6.1 when rendering "onclick scripts", pass label text through wikifyPlainText() to parse any embedded wiki-syntax to enable use of HTML entities or even TW macros to generate dynamic label text.
2007.02.19 1.6.0 added support for title="..." to specify mouseover tooltip when using an onclick (label="...") script
2006.10.16 1.5.2 add newline before closing '}' in 'function out_' wrapper. Fixes error caused when last line of script is a comment.
2006.06.01 1.5.1 when calling wikify() on script return value, pass hightlightRegExp and tiddler params so macros that rely on these values can render properly
2006.04.19 1.5.0 added 'show' parameter to force display of javascript source code in tiddler output
2006.01.05 1.4.0 added support 'onclick' scripts. When label="..." param is present, a button/link is created using the indicated label text, and the script is only executed when the button/link is clicked. 'place' value is set to match the clicked button/link element.
2005.12.13 1.3.1 when catching eval error in IE, e.description contains the error text, instead of e.toString(). Fixed error reporting so IE shows the correct response text. Based on a suggestion by UdoBorkowski
2005.11.09 1.3.0 for 'inline' scripts (i.e., not scripts loaded with src="..."), automatically replace calls to 'document.write()' with 'place.innerHTML+=' so script output is directed into tiddler content. Based on a suggestion by BradleyMeck
2005.11.08 1.2.0 handle loading of javascript from an external URL via src="..." syntax
2005.11.08 1.1.0 pass 'place' param into scripts to provide direct DOM access
2005.11.08 1.0.0 initial release
<<<
<<list filter [tag[Insect]]>>
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//This post was originally published in my column [[NaturePhiles|http://www.talkingscience.org/category/naturephiles/]] on [[Talking Science|http://www.talkingscience.org/2012/02/its-a-bird-its-a-plane-its-a-gliding-mammal/]].//
Gliding mammals sail silently from one tree to the next, maneuvering to their destinations with extraordinary precision and control, often in complete darkness. This unique ability is found in only about 60 species of mammals in the world, but those species include marsupials and placental animals, two very distantly related groups distinguished by the vast evolutionary differences in their reproductive systems. As a result, gliding mammals serve as a fascinating example of convergent evolution -- when similar physical and functional traits occur in unrelated species.
All gliding mammals share several key features, the most notable of which is the presence of a thin membrane of skin that runs between the forelimb and hind limb on each side of the body. When the animal leaps into the air and extends its feet outward, these membranes, known as patagia, become stretched by air pressure, essentially turning the animal’s body into a rectangular wing that produces lift and sustains gliding. While in the air, gliding mammals actively regulate aerodynamic forces, though often through unique mechanisms. For instance, whereas one species may rely primarily on tail movements to control orientation and trajectory during a glide, another species may rely on a combination of tail, arm, and leg adjustments.
[Img[Images/Sugar_glider.jpg]]
The sugar glider (//Petaurus breviceps//) is a type of gliding mammal. Photo credit: Anke Meyring
Some of the best-known gliding mammals are flying squirrels, which belong to the order Rodentia and are found in temperate and tropical forests in Asia, northern Europe, India, and North America. There are about 44 species of flying squirrels, of which the northern flying squirrel (//Glaucomys sabrinus//) holds the record for the longest glide, at almost 90 meters (295 feet). In addition to patagia, flying squirrels possess other specialized gliding adaptations, including a small shaft of cartilage on each wrist that helps control the patagia during gliding and a bushy, usually flattened tail that acts as a rudder for steering. The woolly flying squirrel (//Eupetaurus cinereus//) of south-central Asia is the largest of the group, weighing as much as 2.5 kg (5.5 pounds) and measuring about 45 to 60 cm (about 1.5 to 2 feet) in length from the head to the base of the tail. The lesser pygmy flying squirrel (//Petaurillus emiliae//) of Borneo is believed to be the smallest, though data on its size is lacking.
Another well-known gliding mammal is the sugar glider (//Petaurus breviceps//), which is one of six species of so-called wrist-winged gliders (genus //Petaurus//) of the order Diprotodontia that inhabit the forests of parts of northern and eastern Australia, New Guinea, and nearby islands. Wrist-winged gliders differ from flying squirrels in several ways, perhaps the most significant being that gliders are marsupials and flying squirrels are placental mammals. In addition, the attachment site of the patagia of wrist-winged gliders is the fifth finger of each forelimb, which differs from the cartilaginous attachment structure of flying squirrels. The sugar glider is the smallest member of //Petaurus//, weighing 80 to 170 grams (2.8 to 6 ounces) and measuring 15 to 21 cm (6 to 8 inches) in body length. The largest of the group is the yellow-bellied glider (//Petaurus australis//), which weighs 450 to 700 grams (1 to 1.5 pounds) and measures around 30 cm (1 foot) in body length.
[Img[Images/Colugo.jpg]]
The Sunda flying lemur (//Galeopterus variegatus//). Photo credit: Nina Holopainen
Other gliding mammals include the greater glider (//Petauroides volans//) and the feather-tailed glider (//Acrobates pygmaeus//), which are members of Diprotodontia, and the colugos (or flying lemurs, though they are not related to true lemurs) of Southeast Asia, which belong to the order Dermoptera. The two extant species of colugos are the Philippine flying lemur (//Cynocephalus volans//) and the Sunda flying lemur (//Galeopterus variegatus//). These animals have a patagium that extends from the shoulders to the tip of the tail, and they have webbed feet. Thus, colugos have more developed gliding capabilities compared with flying squirrels and gliding marsupials. These capabilities led to the proposal in the 1980s that colugos were very closely related to bats, but this idea has since been rejected by DNA analyses.
The physical differences and variations in aerodynamic control among gliding mammals are the result of independent evolutionary events. In fact, gliding evolved independently at least nine times in mammals, and each time, it came about through a series of increasingly sophisticated adaptations that provided greater control over aerial descent. While there is no clear explanation yet as to why some arboreal mammals took to aerial descent as a mode of locomotion in the first place, scientists suspect that habitat structure, predators, aerodynamic and landing forces associated with leaping or jumping, and energy expenditure during foraging may have been important factors.
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Oct. 22, 2011:
In StyleSheet, to center web page, changed:
#contentWrapper{
margin: 0 3.4em;
...
to:
#contentWrapper{
border: 0;
margin: 0 auto;
width: 960px;
...
Oct. 22, 2011:
In PageTemplate, to align right edge of image with blue bar under header, changed:
<div id='header' class='header' style='max-width: 910px;'>
to:
<div id='header' class='header' style='max-width: 950px;'>
My personal favorite...
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Kirtland's warbler (//Dendroica kirtlandii//) is one of North America's rarest species of songbird.
For more, see: [[A Warbler Rises from the Ashes]].
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{{nobullets{<<list filter [tag[Life1]]>>}}}
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//The following originally appeared in Naturephiles on ~TalkingScience.org and was republished on the [[Britannica Blog|http://www.britannica.com/blogs/2011/09/lightinsensitive-cavefish-provide-insight-circadian-rhythm/]].//
Each day, living organisms cycle through a series of physiological changes that correspond roughly to the 24-hour day-night cycle. In many species, this internal clock, known as circadian rhythm, is dictated by exposure to light. But what about species that are never exposed to light? A [[study|http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001142]] comparing the Somalian cavefish //Phreatichthys andruzzii//, which has a 47-hour rhythm that functions in the complete absence of light, with zebrafish (//Danio rerio//), which experience typical day-night cycles, revealed that there is in fact much more to circadian rhythm than light alone.
The study, conducted by scientists in Europe and published in //PLoS Biology//, examined the activity of zebrafish genes thought to influence circadian rhythm and the homologs of those genes in //P. andruzzii// following exposure to different light and dark cycles and to changes in food availability. The researchers found that even after exposure to alternating 12-hour periods of light and dark, //P. andruzzii// remained insensitive to light and maintained a food-driven infradian rhythm (an internal clock maintained on a 28-hour or longer cycle). This observation was not all that surprising, given that //P. andruzzii//'s eyes undergo degeneration during development, leaving it blind.
More intriguing, however, was the discovery that light may not be the only factor guiding circadian rhythm in light-sensitive species. This discovery came following a month-long experiment in which both //P. andruzzii// and zebrafish were fed at the same time each day and the activity of different clock genes measured. The only clock genes active in cavefish were those responsive to food. In zebrafish, however, genes producing responses to light and food, rather than simply light alone, were active.
The researchers compared the genes encoding light-responding cells known as photoreceptors in cavefish and zebrafish, looking specifically at two receptors—melanopsin and TMT (teleost multiple tissue)-opsin—that are thought to play a non-visual role in light detection and circadian rhythm. The investigation revealed that //P. andruzzii// has truncated forms of melanopsin and TMT-opsin that lack the regions implicated in light detection. When the zebrafish versions of these genes were inserted into the DNA of //P. andruzzii//, light sensitivity in cavefish was rescued. This suggests that melanopsin and TMT-opsin do in fact influence non-visual light sensitivity and therefore circadian rhythm.
The internal clock of //P. andruzzii//, however, appears to be quite complex. For instance, when the cavefish carrying the introduced zebrafish genes were treated with glucocorticoids, which in the laboratory can be used to trigger the rhythmic activity of clock genes, the cavefish slipped into a 43-hour cycle. Changes in temperature also influenced //P. andruzzii//'s internal clock but had little influence on zebrafish. Hence, more research is needed to fully understand //P. andruzzii//'s internal clock.
Additional investigation of factors other than light that influence circadian rhythm in light-sensitive animals could provide important insight into the internal clocks of a wide variety of species, including humans. Disruption of circadian rhythm is a source of stress that in humans can contribute to fatigue, sleep disorders, and depression.
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The little brown myotis, or little brown bat (//Myotis lucifugus//), is one of the most abundant mouse-eared bats (//Myotis//) in North America, being found in most U.S. states and in Canada. In the north it is found from central Alaska to Labrador in northeastern Canada. The southern end of its range extends to Arkansas.
As its name suggests, the little brown myotis is little, weighing just 0.025 to 0.5 ounce and measuring about 2.5 to 4 inches in body length, and its upper surface is brown in color, while its underparts are gray. It hibernates in the winter, with individuals gathering into large groups and colonizing cool, humid caves, where temperatures are a steady 40 °F and humidity levels hover around 90 percent. In the summer, the little brown myotis roosts in warm areas, most commonly under the roofs of barns and similar buildings. The little brown myotis feeds on insects and favors wetland habitat, where mosquitoes, midges, gnats, and other insects are abundant, enabling it to consume up to half its body weight in insects each night. Its lifespan is 20 to 30 years in the wild.
In 2005-06 scientists learned of a disease known as white nose syndrome (WNS), which was later associated with a newly discovered species of fungus, //Geomyces destructans//. WNS poses a major threat to bat survival. The fungus grows in bat hibernicula and infects the skin and connective tissue of the wings, thereby disrupting hibernation and causing the bat to expend energy to stay warm after wakening. Bats that are repeatedly awakened from hibernation starve, become dehydrated, and eventually die. Some bats fly out of their caves in mid-winter in search of food and water, only to perish from exposure to cold. Bats that survive infection may have signs of impaired wing function, which can affect flying efficiency, leading to declines in foraging and reproductive success. Estimates indicate that by the end of winter 2012, WNS will have killed a total of 2 million bats, many of which have been little brown bats, since its discovery.
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[img[Buy it from The University of Arizona Press|Images/Rogers_small_QE_cover.jpg][http://www.uapress.arizona.edu/Books/bid2541.htm]]
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<html>
<img src="Images/worldmap_small.jpg" width="700" height="355" alt="Worldmap" usemap="#worldmap_small" />
<map name="worldmap_small">
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<area shape="rect" coords="324,39,570,150" href="index.html#[[Eurasia]]" alt="Eurasia" />
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<area shape="rect" coords="6,192,99,237" href="index.html#[[Oceania]]" alt="Oceania" />
<area shape="rect" coords="427,172,532,258" href="index.html#[[Indian%20Ocean]]" alt="The Indian Ocean" />
</map>
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<<closeAll>><<permaview>><<newTiddler>><<newJournal 'DD MMM YYYY'>><<saveChanges>><<slider chkSliderOptionsPanel OptionsPanel 'options »' 'Change TiddlyWiki advanced options'>>
As the largest member of the deer family (Cervidae), the moose (//Alces alces//) is a conspicuous member of the fauna inhabiting North America and Eurasia. Four subspecies of moose are recognized: the Alaskan moose (//Alces alces gigas//), found in Alaska, the western Yukon, and northwestern British Columbia; the Shiras moose (//Alces alces shirasi//), found along the Rocky Mountains from Canada to Colorado; the northwestern moose (//Alces alces andersoni//), found in the northern parts of Michigan and Minnesota and in central Canada; and the eastern moose (//Alces alces americana//), found in the northeastern United States and eastern Canada.
The Alaskan moose is the largest of the group, with full-grown bulls weighing 1,200 to 1,600 pounds and measuring about 7 feet at the shoulder. Adult females, on the other hand, are smaller, weighing about 800 to 1,300 pounds. The Shiras moose is the smallest subspecies.
In Eurasia, moose are found in northern areas, such as northern Europe (e.g., Norway, Finland, and the Baltic States) and Russia, as well as countries in the east, such as the Ukraine and Belarus.
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{{nobullets{<<list filter [tag[Nature1]]>>}}}
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
In the last few weeks, I've added information on some fascinating species found in the Americas and Eurasia:
[[Gray wolf|Gray wolf]]
[[Moose|Moose]]
[[Little brown myotis|Little brown myotis]]
[[Bumblebee bat|Bumblebee bat]]
Back to [[The Nature Beat|The Nature Beat]]
Back to [[The Americas|The Americas]]
Back to [[Eurasia|Eurasia]]
<<tiddler HideTiddlerTags>>
!Canada
!Greenland
!United States
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
Last Updated: 8/24/2015
Copyright © Kara Rogers
kerogers (at) nasw.org
More Naturephiles on the Science Friday blog:
[[The Numbat: A Most Unusual Marsupial|http://sciencefriday.com/blogs/08/07/2012/the-numbat-a-most-unusual-marsupial.html]]
[[Life in the Street Canyon: The Role of Plants in Maintaining Air Quality|http://sciencefriday.com/blogs/07/24/2012/life-in-the-street-canyon-the-role-of-plants-in-maintaining-air-quality.html?series=2&interest=&audience=&author=]]
[[The Contagious Nature of Yawning|http://sciencefriday.com/blogs/07/17/2012/the-contagious-nature-of-yawning.html?series=2&interest=&audience=&author=]]
[[Mosquitoes Go With the Flow When Flying in the Rain|http://sciencefriday.com/blogs/06/26/2012/mosquitoes-go-with-the-flow-when-flying-in-the-rain.html?series=2&interest=&audience=&author=]]
Back to [[The Nature Beat|The Nature Beat]]
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<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
<<list filter [tag[Oceania1]]>>
Back to [[Map|Map]]
Back to [[Species by Region|Species by Region]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<list filter [tag[Ocean]]>>
Back to [[In the Water|In the Water]]
Back to [[Species by Region|Species by Region]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
[[Birds of the Americas]]
[[Birds of Eurasia]]
[[Birds of Africa]]
[[Birds of Antarctica]]
[[Birds of Oceania]]
[[Seabirds]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
The orange clownfish (//Amphiprion percula//) is found in the Pacific Ocean, from northeastern Australia to Melanesia. It is known for its bright orange color, marked by three wide white vertical bars edged in black. It lives in close relationship with sea anemones in shallow reef waters, where water temperatures are about 25 to 28 °C and where there is sufficient sunlight to support the photosynthetic golden-brown algae that live on the anemones.
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Today was the official launch of [[outofnature.net|http://outofnature.net]], where visitors can learn more about my forthcoming book //Out of Nature: Why Drugs from Plants Matter to the Future of Humanity//. The web site features, among other things, a synopsis of the book, an extensive plant taxonomy section, and links to places where the book can be purchased. It'll be out in print in February 2012. Happy reading!
Back to [[The Nature Beat|The Nature Beat]]
<<tiddler HideTiddlerTags>>
<<list filter [tag[Pacific]]>>
Back to [[Map|Map]]
Back to [[Oceans|Oceans]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<!--{{{-->
<div id='header' class='header' style='max-width: 950px;'>
<div class='headerShadow'>
<span class='siteTitle' refresh='content' tiddler='SiteTitle'></span>
<span class='siteSubtitle' refresh='content' tiddler='SiteSubtitle'></span>
</div>
</div>
<div id='mainMenu'>
<span refresh='content' tiddler='MainMenu'></span>
<span class='searchBar' macro='search'></span>
<span id='noticeBoard' refresh='content' tiddler='NoticeBoard'></span>
</div>
<div id='sidebar'>
<div id='sidebarOptions' refresh='content' tiddler='MochaSideBarOptions'></div>
<div id='sidebarTabs' refresh='content' force='true' tiddler='SideBarTabs'></div>
</div>
<div id='displayArea' style='max-width: 750px;'>
<div id='messageArea'></div>
<div id='tiddlerDisplay'></div>
</div>
<div id='contentFooter' refresh='content' tiddler='contentFooter'></div>
<!--}}}-->
//The following was originally published in Naturephiles on ~TalkingScience.org and was republished on the Encyclopaedia Britannica's [[Advocacy for Animals|http://advocacy.britannica.com/blog/advocacy/2014/06/pint-size-pika-threatened-by-climate-change/]] blog.//
Chirping from the talus slopes of the Teton Range in the Rocky Mountains, the American pika (//Ochotona princeps//) sends a warning call to intruders — in this case humans climbing up the switchbacks in Grand Teton National Park’s Cascade Canyon. Sounding its alarm from a rocky perch, then darting into crevices and shadow on the steep slope, the rodent-sized, round-eared, brownish gray pika goes largely unnoticed. But as the second species petitioned for protection under the U.S. Endangered Species Act (ESA) because of climate change-associated threats (the polar bear was the first), the pika cannot afford to be overlooked for much longer.
The American pika lives primarily at elevations between 8,000 and 13,000 feet, though it may be found at significantly lower elevations, including a little above sea level. Low-elevation pika populations, however, are at high risk of climate change, particularly local warming and decreased precipitation. Populations of pika in Yosemite National Park, for example, have migrated more than 500 feet upslope over the course of the last century, a shift coincident with a temperature increase of 5.4 °F in Yosemite during that same period of time. More significantly, over the course of only a decade — between 1999 and 2008 — pikas in the Great Basin on the eastern edge of the Sierra Nevada experienced a nearly five-fold increase in extinction rate and an 11-fold increase in the rate of upslope retreat. Pikas there are now moving upslope at a rate of 475 feet per decade.
In 2010, despite the documented loss of pikas and evidence linking pika declines and range shifts with climate change, the U.S. Fish and Wildlife Service (FWS) decided not to protect the American pika under the ESA. The decision was denounced by the nonprofit Centers for Biological Diversity, which had petitioned for the species’ protection, and was supported by some biologists, who claimed that most populations of the American pika are stable.
Pikas, however, are highly susceptible to warm temperatures and will die within several hours of constant exposure to temperatures of 75 to 78 °F. Their survival also appears to depend heavily on contiguous habitat. For instance, a study of historical pika population sites in the southern Rockies, where pika habitat extends over a large area, revealed that just four out of 69 populations had been extirpated since the 1980s. The extirpations occurred at sites that were once wet but that had dried out over the course of the last 100 years.
Contiguous habitat and upslope migration are the pika’s only hope for escape from local climate warming and drying. But at higher elevations, food may be scarce and the climate too cold, and given the isolation of pika populations, it remains to be seen whether migration and dispersal to new areas can actually rescue the species. Furthermore, several decades into the future, the high, mountainous elevations where pikas can now find refuge may no longer be cool and wet enough to support their survival.
Indeed, climate prediction models have suggested that summertime temperatures in pika habitat will increase by 5.4 °F by 2050. While the FWS cited this figure in its report explaining why pika do not warrant protection under the ESA, such an increase will render the lower elevations of many mountain ranges, including the Teton Range, uninhabitable for pika. And while it is difficult to predict precise temperature increases beyond 2050, temperatures likely will continue to rise, forcing the American pika higher and higher, further restricting its range and its chances of survival in the process.
Back to [[Nature]]
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Back to [[On the Land|On the Land]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Back to [[On the Land|On the Land]]
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//Ursus maritimus//
[img[polar_bear3.jpg]]
Photo by Susanne Miller
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Polar bears (//Ursus maritimus//) live in the cold, ice-encrusted Arctic and are often found atop floating ice sheets. They have thick fur coats and an insulating fat layer under their skin that helps them stay warm. Polar bears are good swimmers, sometimes obtaining speeds of more than 6 mph. They use their front legs to pull themselves along and their hindlegs to steer. Polar bears are carnivores, eating mainly seals, fish, whale carcasses, and reindeer and occasionally feeding on berries and kelp.
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The pronghorn (//Antilocapra americana//) is found on the plains, deserts, and grasslands of North America. Although it looks very much like an antelope, it is actually a distant relative. In fact, the pronghorn is classified in an entirely separate family, Antilocapridae. It is the only living representative of this family, a distinction due in part to its atypical horns.
The horns of the pronghorn are flattened, hollow, and branched. One of the branches forms a forward-pointing prong, for which the animal is named. Unlike animals such as antelope, goats, and bison (which have hollow, unbranching horns that are not shed) and animals such as deer and elk (which have solid, branching horns that are shed), pronghorn shed their hollow horns annually. Both male and female pronghorns have horns (the horns of females often are absent or much reduced in size), a trait they share in common with reindeer.
[img[Images/pronghorn1_small.JPG]]
Photo credit: Jeremy D. Rogers
[img[Images/pronghorn2_small.JPG]]
Photo credit: Jeremy D. Rogers
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Also known as the fire lobe of the chimney, //Pyrolobus fumarii// is the most heat-tolerant organism on Earth, surviving at a record high of 235 °F. In 1997 German microbiologist Karl O. Stetter discovered //P. fumarii// in the wall of a black smoker (a hydrothermal vent named for the black plumes created as the sulfide minerals it emits mix with the cold surrounding water). The smoker was located about 12,000 feet below the ocean’s surface in the Mid Atlantic Ridge. Hence, the organism tolerates not only extremely hot water with high concentrations of sulfide minerals but also pressures as high as 250 bars (3,625 psi; life at sea level experiences just 14.7 psi).
//P. fumarii// is a chemolithoautotroph, meaning it eats inorganic chemicals, hydrogen, and carbon dioxide; it extracts these chemicals from the walls of black smokers. //P. fumarii// has a genome that consists of about 2,000 genes, many of which share very little or no similarity with genes of other microorganisms. This suggests that //P. fumarii// is genetically fit for life in extreme heat.
[img[Images/black_smoker.jpg]]
A black smoker at a mid-ocean ridge hydrothermal vent.
Credit: OAR/National Undersea Research Program (NURP); NOAA
Read more about //P. fumarii//: [[Life in the Smoker: The Fire Lobe of the Chimney|http://www.talkingscience.org/2011/11/life-in-the-smoker-the-fire-lobe-of-the-chimney/]]
Back to [[Microorganisms|Microorganisms]]
Back to [[Tiny Life|Tiny Life]]
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The red-billed quelea (//Quelea quelea//) is one of world's most abundant birds. It inhabits the savanna and low-lying veld of sub-Saharan Africa, where, in a single day, it may consume one-half or more of its own body weight of grain. Giant flocks of queleas land in fields of cereal crops, causing massive destruction. Indeed, this finchlike songbird is a major pest in Africa.
The red-billed quelea has remarkably complex feeding and migration strategies, oriented around local rainfall and seed and insect abundance. Learn more about the quelea in [[The Red-Billed Quelea: Africa’s Avian Riff-Raff|http://www.talkingscience.org/2010/12/the-red-billed-quelea-africas-avian-riff-raff/]].
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/%
|Name|ReplaceDoubleClick|
|Source|http://www.TiddlyTools.com/#ReplaceDoubleClick|
|Version|2.0.0|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|script|
|Requires|InlineJavascriptPlugin|
|Overrides|tiddler background click and doubleclick handlers|
|Description|disable doubleclick-to-edit-tiddler or replace doubleclick with shift/ctrl/alt+singleclick|
Usage:
in tiddler content:
<<tiddler ReplaceDoubleClick>> or
<<tiddler ReplaceDoubleClick with: key trigger>>
in ViewTemplate:
<span macro="tiddler ReplaceDoubleClick"></span> or
<span macro="tiddler ReplaceDoubleClick with: key trigger"></span>
where:
'key' (optional) is one of: none (default), ctrl, shift, or alt
'trigger' (optional) is one of: click, doubleclick (default)
* if no key parameter (or "none") is specified, then the double-click action is **disabled** for that tiddler.
* if a key (other than none) is specified, the doubleclick action for the tiddler will only be invoked
when the key+trigger combination is used.
* note: double-clicking will also trigger the single-click handler. As a result, when 'click' option is specified,
either click OR double-click (plus the specified key) will trigger the action.
Revisions:
2.0.0 renamed from ShiftClickToEdit and merged with DoubleClickDisable and added support specifying alternative key+click combination
%/<script>
var here=story.findContainingTiddler(place); if (!here) return;
if (here.ondblclick) {
here.setAttribute("editKey","none");
if ("$1"=="shift" || "$1"=="ctrl" || "$1"=="alt")
here.setAttribute("editKey","$1"+"Key");
var trigger=("$2"=="click")?"onclick":"ondblclick";
here.save_dblclick=here.ondblclick;
here.ondblclick=null;
if (here.getAttribute("editKey")!="none")
here[trigger]=function(e) {
var ev=e?e:window.event;
if (ev[this.getAttribute("editKey")])
this.save_dblclick.apply(this,arguments);
}
}
</script>
*[[A link]]
*[[A link]]
*[[A link]]
*<<closeAll>>
*<<permaview>>
*<<saveChanges>>
Ringed seals (//Pusa hispida//) are named for the pale rings that appear on their gray bodies, primarily on the back. They are widely distributed in the circumpolar oceans of the Northern Hemisphere. They feed on arctic cod, mollusks, and planktonic crustaceans. Although they are common, because they depend on sea ice for breeding and molting, climate change is considered a threat to their existence.
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<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
//The following was originally published in Naturephiles on [[ScienceFriday.com|http://www.sciencefriday.com/blogs/10/22/2012/riverside-s-rodent-the-kangaroo-rat-that-stood-up-to-development.html?audience=2&series=2]].//
The endangered Stephen's kangaroo rat actually is not a rat -- it is more closely related to rodents such as squirrels and gophers than it is to notorious pests like the Norway rat and house rat. But those opposed to the animal's protection might be tempted to invoke the misconception. In 1993 the tiny, two-ounce, cinnamon-furred creature was blamed for the loss of homes from a brushfire in Riverside County, Southern California, and more recently it has been viewed as an impediment to job-creating development in the region.
Earlier this year, developers and conservationists agreed to split nearly 1,200 acres of land lying west of the March Air Reserve Base in Riverside County. Approximately 660 acres will go to the conservation of the kangaroo rat. The land, however, which had been targeted for industrial development, originally belonged in its entirety to the U.S. Fish and Wildlife Service (FWS). It had been set aside in the 1990s as the March Stephens' Kangaroo Rat Preserve. The following decade, however, the FWS gave it to commercial developers, accepting a parcel of preservable land farther away from Riverside in exchange. The trade, however, threatened to break up a corridor of preserves on which a variety of native species depend.
The Stephen's kangaroo rat (//Dipodomys stephensi//) is an unusual creature. Like other kangaroo rats, it is known for its long, rat-like tail and large, kangaroo-like hind feet -- traits that arguably work against it when it comes to shedding the “rat” label. But identity crisis aside, real conflicts do exist when it comes to the animal's conservation and human interests in the Riverside area, which is the animal's last native refuge. There, in addition to its impact on development, the kangaroo rat has also been a potential concern for farmers, because of its taste for crop seeds. Its conservation has been further complicated by mixed perceptions about how Southern California's habitats should be managed.
Conservation scientists have been working to maintain the region's native coastal sage scrub and chaparral-grass habitat. To do so, however, has required prescribed burns, which keep nonnative species out and maintain the open character of the region's native habitats. (Fire suppression in the 20th century had caused some areas of local scrubland to begin to mature into woodland, squeezing out flora and fauna adapted to the scrub environment.) Controlled burns may also help to limit the severity and frequency of destructive, high-intensity fires brought on by fire suppression and drought.
The kangaroo rat, through its consumption of seeds of wild plants, helps to prevent the succession of desert scrubland to woodland. Its presence also is important for prey species such as coyotes and foxes and barn owls and long-eared owls, animals that add to the character of the Southern California landscape. And other species in the area, such as bobcats and the endangered coastal California gnatcatcher (//Polioptila californica//), benefit from the conservation of the kangaroo rat's habitat, too.
The kangaroo rat's conflict with humans has been lessened somewhat by efforts to translocate animals, moving them from areas where they are under particular duress to the Southwestern Riverside County ~Multi-Species Reserve, for example. But while translocation has been beneficial, protection of the Stephen’s kangaroo rat continues to be challenged by the general lack of knowledge about the animal, especially concerning its reproductive and social behavior. Adults are solitary, and they emerge from their underground burrows to forage for just one hour each night, making them elusive and their study difficult.
Cultivating a sense of appreciation for an animal like the Stephen's kangaroo rat is not a simple task, particularly given residents' fears about the potential for prescribed burns to grow into uncontrollable fires and popular notions about woodlands, which may be ascribed superior aesthetic value compared with scrublands. But there are five other endangered species of kangaroo rats in California. And all -- like the state's rugged coast and interior mountains -- are inherently valuable and, in this author's opinion, deserving of protection.
Back to [[Nature]]
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{{nobullets{<<list filter [tag[Science1]]>>}}}
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
Back to [[Major Seas|Major Seas]]
Back to [[Bodies of Water|Bodies of Water]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
<<list filter [tag[Sea]]>>
<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
<<list filter [tag[Seabird]]>>
Back to [[On the Wing|On the Wing]]
Back to [[Map|Map]]
<<tiddler HideTiddlerTags>><<tiddler HideTiddlerSubtitle>><<tiddler HideTiddlerToolbar>>
The secretary bird (//Sagittarius serpentarius//), also known as the marching eagle, inhabits the plains of sub-Saharan Africa and is the only terrestrial bird of prey. It may travel, by foot, as many as 20 miles in a single day in search of prey. The secretary bird is found primarily in open areas, such as grasslands, savannas, and semi-desert regions. Its range extends from Senegal in the west to Ethiopia and Somalia in the east; the southernmost it has been found is the Cape Peninsula in South Africa. Secretary birds eat small mammals as well as insects, snakes, amphibians, and other birds or bird eggs.
The bird may have been named for the raised crest of black feathers on its head, which resemble the quill pens historically carried behind secretaries' ears. //Sagittarius//, however, means "archer," a name possibly given in reference to the pointed crest feathers. Also, the Arabic //saqr-et-tair//, which means "hunter-bird," sounds similar to the French //secrétaire// and may have served as the origin of the secretary bird's name.
Read more about the secretary bird: [[The Marching Eagle: Africa’s Secretary Bird|http://www.talkingscience.org/2011/11/the-marching-eagle-africas-secretary-bird/]]
Back to [[Life]]
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<<tiddler HideTiddlerTags>>
<<tiddler HideTiddlerSubtitle>>
<<tiddler HideTiddlerToolbar>>
/***
|Name|SinglePageModePlugin|
|Source|http://www.TiddlyTools.com/#SinglePageModePlugin|
|Documentation|http://www.TiddlyTools.com/#SinglePageModePluginInfo|
|Version|2.9.6|
|Author|Eric Shulman - ELS Design Studios|
|License|http://www.TiddlyTools.com/#LegalStatements <br>and [[Creative Commons Attribution-ShareAlike 2.5 License|http://creativecommons.org/licenses/by-sa/2.5/]]|
|~CoreVersion|2.1|
|Type|plugin|
|Requires||
|Overrides|Story.prototype.displayTiddler(), Story.prototype.displayTiddlers()|
|Options|##Configuration|
|Description|Show tiddlers one at a time with automatic permalink, or always open tiddlers at top/bottom of page.|
This plugin allows you to configure TiddlyWiki to navigate more like a traditional multipage web site with only one tiddler displayed at a time.
!!!!!Documentation
>see [[SinglePageModePluginInfo]]
!!!!!Configuration
<<<
<<option chkSinglePageMode>> Display one tiddler at a time
><<option chkSinglePagePermalink>> Automatically permalink current tiddler
><<option chkSinglePageKeepFoldedTiddlers>> Don't close tiddlers that are folded
><<option chkSinglePageKeepEditedTiddlers>> Don't close tiddlers that are being edited
<<option chkTopOfPageMode>> Open tiddlers at the top of the page
<<option chkBottomOfPageMode>> Open tiddlers at the bottom of the page
<<option chkSinglePageAutoScroll>> Automatically scroll tiddler into view (if needed)
Notes:
* The "display one tiddler at a time" option can also be //temporarily// set/reset by including a 'paramifier' in the document URL: {{{#SPM:true}}} or {{{#SPM:false}}}.
* If more than one display mode is selected, 'one at a time' display takes precedence over both 'top' and 'bottom' settings, and if 'one at a time' setting is not used, 'top of page' takes precedence over 'bottom of page'.
* When using Apple's Safari browser, automatically setting the permalink causes an error and is disabled.
<<<
!!!!!Revisions
<<<
2008.10.17 [2.9.6] changed chkSinglePageAutoScroll default to false
| Please see [[SinglePageModePluginInfo]] for previous revision details |
2005.08.15 [1.0.0] Initial Release. Support for BACK/FORWARD buttons adapted from code developed by Clint Checketts.
<<<
!!!!!Code
***/
//{{{
version.extensions.SinglePageModePlugin= {major: 2, minor: 9, revision: 6, date: new Date(2008,10,17)};
//}}}
//{{{
config.paramifiers.SPM = { onstart: function(v) {
config.options.chkSinglePageMode=eval(v);
if (config.options.chkSinglePageMode && config.options.chkSinglePagePermalink && !config.browser.isSafari) {
config.lastURL = window.location.hash;
if (!config.SPMTimer) config.SPMTimer=window.setInterval(function() {checkLastURL();},1000);
}
} };
//}}}
//{{{
if (config.options.chkSinglePageMode==undefined)
config.options.chkSinglePageMode=false;
if (config.options.chkSinglePagePermalink==undefined)
config.options.chkSinglePagePermalink=true;
if (config.options.chkSinglePageKeepFoldedTiddlers==undefined)
config.options.chkSinglePageKeepFoldedTiddlers=false;
if (config.options.chkSinglePageKeepEditedTiddlers==undefined)
config.options.chkSinglePageKeepEditedTiddlers=false;
if (config.options.chkTopOfPageMode==undefined)
config.options.chkTopOfPageMode=false;
if (config.options.chkBottomOfPageMode==undefined)
config.options.chkBottomOfPageMode=false;
if (config.options.chkSinglePageAutoScroll==undefined)
config.options.chkSinglePageAutoScroll=false;
//}}}
//{{{
config.SPMTimer = 0;
config.lastURL = window.location.hash;
function checkLastURL()
{
if (!config.options.chkSinglePageMode)
{ window.clearInterval(config.SPMTimer); config.SPMTimer=0; return; }
if (config.lastURL == window.location.hash) return; // no change in hash
var tids=decodeURIComponent(window.location.hash.substr(1)).readBracketedList();
if (tids.length==1) // permalink (single tiddler in URL)
story.displayTiddler(null,tids[0]);
else { // restore permaview or default view
config.lastURL = window.location.hash;
if (!tids.length) tids=store.getTiddlerText("DefaultTiddlers").readBracketedList();
story.closeAllTiddlers();
story.displayTiddlers(null,tids);
}
}
if (Story.prototype.SPM_coreDisplayTiddler==undefined)
Story.prototype.SPM_coreDisplayTiddler=Story.prototype.displayTiddler;
Story.prototype.displayTiddler = function(srcElement,tiddler,template,animate,slowly)
{
var title=(tiddler instanceof Tiddler)?tiddler.title:tiddler;
var tiddlerElem=document.getElementById(story.idPrefix+title); // ==null unless tiddler is already displayed
var opt=config.options;
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Freelance science writer Kara Rogers<<tiddler ToggleRightSidebar with: ".">>
[img[Images/header.jpg]]
Nature. Science. Life.{{justifyright{[img[Twitter|Images/twitter_nature_icon.png][http://twitter.com/#!/karaerogers]]
}}}
The Somalian cavefish (//Phreatichthys andruzzii//) is a blind species of fish that is known particularly for its food-driven, 47-hour infradian rhythm (a circadian rhythm greater than 28 hours). It is also quite small, growing to a maximum length of just 2.4 inches.
For more, see:
[[Light-Insensitive Cavefish Provide Insight into Circadian Rhythm]]
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!Brazil
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//The following was originally published in Naturephiles on ~TalkingScience.org and was republished on the [[Britannica Blog|http://www.britannica.com/blogs/2011/12/space-worms-biological-impact-longduration-spaceflight/]].//
Space explorers and science fiction authors have long dreamed of space colonization, of the day when the human species will inhabit distant planets. Habitable planets, however, lie beyond the roughly 1,200-mile-boundary of low Earth orbit (LEO), which humans have not flown past since the final Apollo mission in December 1972. Indeed, beyond-LEO travel is fraught with technological and logistical issues. And it poses significant challenges to human survival—problems that researchers are now addressing through studies in space with the worm //Caenorhabditis elegans//, an organism that shares 40 to 50 percent genetic similarity with humans and hence offers insight into potential impacts of distant space travel on human physiology.
In a [[paper|http://rsif.royalsocietypublishing.org/content/early/2011/11/22/rsif.2011.0716.full]] published in the //Journal of the Royal Society Interface//, scientists from the United States, United Kingdom, and Canada described an automated, remotely monitored culture system for growing //C. elegans// during long-duration LEO spaceflight. The scientists successfully tested the system in a six-month-long trial aboard the International Space Station (ISS) and now say that the automated system is ready for deployment on unmanned missions beyond LEO, to other planets, such as Mars.
The worms lived in specialized culture cells connected by peristaltic pumps and filled with a liquid medium that supported their survival. For launch and flight to the ISS, the worms were maintained in a growth-arrested state, which helped them resist stress. Once aboard the space station, they were revived through feeding and began to grow and reproduce. Their growth, reproduction, and movement in response to long-duration spaceflight were monitored and analyzed from a laboratory on Earth via remote uplink to cameras mounted on the culture cells. Hence, there was never any need for humans aboard the ISS to handle the cells.
The scientists observed //C. elegans// for 12 generations in space and compared their findings with their observations of Earth-bound worms, which served as controls. The comparisons revealed that long-duration flight aboard the ISS had no effect on worm development. In addition, when fully fed, space //C. elegans// demonstrated rates of movement comparable to their Earth counterparts, and when deprived of food, both populations showed similar declines in movement, which recovered to normal after feeding. The experiments demonstrated not only that //C. elegans// could serve as a biological model in long-duration spaceflight but also that a biological species could reproduce and grow normally under spaceflight conditions.
Unmanned missions using space worms as biological models offer key advantages to understanding the effects of long-duration, beyond-LEO travel on living organisms. For example, it is far less expensive and much safer to send worms into space instead of humans. In addition, the success of the liquid life-support system designed for //C. elegans// may help scientists conceive of new ideas for mechanisms of human life support and radiation shielding technologies, which will be required for space colonization. Radiation in space, in fact, is a significant threat to human health and survival.
While space colonization likely remains a long way off, the need to escape from Earth in the future may be real, and it may be approaching more rapidly than we suspect. As the world population grows and resources become scarce, and with another ice age possibly looming a few millennia ahead, the future of our species could someday depend on the human colonization of other planets.
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{{nobullets{<<list filter [tag[Region]]>>}}}[[Oceans]]
[[Major Seas]]
See also [[Map|Map]]
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Stony corals, which include brain and mushroom corals, are the primary reef-building corals. They secrete calcium carbonate, which produces a hard skeleton. The skeletons are glued together by calcium carbonate secreted by a type of red algae known as coralline algae. The layering of coral skeletons and calcium carbonate gives rise to coral reefs.
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//The following was originally published in Naturephiles on ~TalkingScience.org.//
//Pheidole// ants, of which there are more than 1,100 known species, making the genus one of the largest in the taxonomic system, are known for their extraordinary diversity. And among their sundry forms is a “supersoldier” subcaste, a rare group of ant sumo wrestlers. But as a team of scientists from Europe, Canada, and the United States discovered, although supersoldiers are produced by just a few //Pheidole// species and thus are infrequent in nature, all //Pheidole// ants have the potential to produce them, and they have possessed this ability since the genus evolved some 35 to 60 million years ago.
The [[study|http://www.sciencemag.org/content/335/6064/79.abstract]], published in //Science//, revealed that the production of //Pheidole// supersoldiers is the result of a developmental program that likely was present in the common ancestor of all //Pheidole// ants. It also suggested that the production of supersoldiers may be triggered by environmental factors and that repeated stimulation of the developmental program through time allowed the evolution of supersoldier subcastes to occur in parallel in different //Pheidole// species.
Supersoldiers are produced with some frequency in at least eight //Pheidole// species found in the southwestern United States, generally in areas also inhabited by predatory army ants. //Pheidole// species apparently have evolved different strategies to deal with army ant raids; for example, while some species evacuate their nests and flee, others stay put and rely on supersoldiers for defense. When army ants attack, supersoldiers block nest entrances with their large heads, preventing invaders from penetrating the colony. The giants also use their extra large size to intimidate and fight off the enemy.
The researchers began investigating the development of supersoldiers after having observed a supersoldier-like subcaste in a wild colony of //Pheidole morrisi// ants. The supersoldier-like individuals, the team believed, arose from abnormalities in the growth and the development of soldier larvae. To test their hypothesis, they reconstructed the evolutionary history of 11 //Pheidole// species, two of which, //P. obtusospinosa// and //P. rhea//, produce supersoldier subcastes. The analyses revealed that the subcastes evolved independently in these two species, meaning that the subcastes evolved in parallel. This in turn presumably enabled adaptive variation and the emergence of new phenotypes (observable traits) in each species. New phenotypes are vital in helping species' thrive in their environments.
The ability of some //Pheidole// species to repeatedly produce supersoldiers appears to be mediated by a substance known as juvenile hormone, the production of which is thought to be dictated by nutrition, with increased availability of nutrients facilitating the development of supersoldiers. Because the entire //Pheidole// genus was suspected of retaining an ancestral potential for supersoldiers, the researchers exposed //P. hyatti// and //P. spadonia// (two species that do not normally produce supersoldiers) to the chemical methoprene, which mimics juvenile hormone. Following exposure to methoprene, both species produced supersoldier-like ants, indicating that the developmental potential had in fact been retained.
The researchers suspect that the ancestral developmental program of supersoldiers in //Pheidole// is the result of genetic accommodation, a process characterized by the emergence and incorporation of a new phenotype into a population. Genetic accommodation occurs through natural selection, in which environmental factors control the frequency and expression of genes. Possible selection pressures for supersoldier production in //Pheidole// may include nutrient availability and army ant raids.
The limited number of //Pheidole// species that produce supersoldier subcastes suggests that selection pressures favoring the giants have lessened over time. For example, selection for supersoldiers may have been reduced in //P. hyatti// when the species found greater success in nest evacuation compared with supersoldier defense during army ant attacks. Still, all //Pheidole// retain the developmental program for supersoldiers, possibly because its loss would compromise the development of the soldier caste itself.
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//This post was originally published in my column [[NaturePhiles|http://www.talkingscience.org/category/naturephiles/]] on [[Talking Science|http://www.talkingscience.org/2012/01/taking-chance-out-of-species-richness-in-tropical-forests/]].//
Community structure in ecology is defined by species richness and population abundance, characteristics that some scientists have argued are produced by unrelated, chance processes. But [[new research|http://www.sciencemag.org/content/335/6067/464.abstract]] by a team of scientists in Germany and the United States has taken chance out of the biodiversity equation. After uncovering similarities in the community structure of tropical forests in three regions of the world, the scientists concluded that species richness and abundance must be governed by related, deterministic processes, including predation and disease.
The latest research, published in the journal //Science//, is not the first to challenge the notion that chance processes are the major drivers of evolutionary diversification, an idea otherwise known as neutral ecological theory, which was introduced in 2001 by American ecologist Stephen Hubbell. This controversial theory describes speciation and extinction processes as stochastic, or nondeterministic, such that each species progresses and evolves in random fashion in space and time. Thus, under neutral theory, differences between similar species within a community have no bearing on whether or not each species is successful.
[img[Images/rainforest_sm.JPG]]
Rainforest in Victoria, Australia.
Neutral theory is based on what Hubbell described as functional equivalence, the hypothesis that species of similar position within a community experience the same birth, death, dispersal, and speciation rates. Beyond this “symmetry” in vital traits, Hubbell argued, species of the same trophic level may differ in any of a number of ways. Furthermore, as long as symmetry is maintained, complex processes, including competition, may exist in neutral theory. However, important ecological processes, such as predation and disease, are asymmetrical, involving dissimilar species from different trophic levels, and therefore fall beyond the scope of neutral theory.
Neutral theory predicts that evolutionary diversification and population abundance are unrelated across independently evolved ecological communities in different parts of the world. However, as the authors of the //Science// study found, the number of tree species and the number of individuals in tree families were comparable for forest plots in Africa, tropical America (the Neotropics), and Southeast Asia. Between regions, such as between forest plots in Ecuador and Malaysia, correlations were strongest among higher taxonomic groups, namely families and orders, and were weakest among genera and species. In contrast, within regions, such as among forest plots in the Neotropics alone, there were strong correlations in the number of species in genera. The researchers suspect that the latter phenomenon may be due to common ancestry and migration of plants within regions, resulting in the homogenization of floras and similarities in lower level taxonomic structure.
Comparisons with the fossil record revealed that the representation of families and the number of species within families have been conserved within regions over tens of millions of years. Thus, similarities in family-level species richness have persisted in different regions despite independent speciation and extinction processes. The findings suggest that, while nature can be unpredictable, deterministic processes strongly influence tree diversity and abundance at regional levels in tropical forests. These insights could prove valuable to forest conservation and efforts to protect rainforest biodiversity.
While it seems probable that random processes work in tandem with deterministic processes, the scientists also suggest that the abundance and diversity of plant species in tropical forests could be influenced by the ~Janzen-Connell effect. According to this hypothesis, predation on seeds and seedlings by insects, herbivores, and pathogens creates openings between different species of plants, thereby providing opportunity for colonization by other species.
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//This post was originally published in Naturephiles on ~TalkingScience.org and republished on the [[Britannica Blog|http://www.britannica.com/blogs/2011/04/aspen-catkin-fuzzy/]].//
Early spring is a deceiving time. Though the world around us bears a monochrome complexion and there lingers a stubborn coolness that makes summer seem ever distant, plants—from the tiniest grasses and shrubs to the tallest trees—begin gearing up for a burst of growth and regeneration. And after a long, cold winter, one very welcome, though very subtle, event is the emergence of aspen catkins, a clear indication that spring—despite the grayness that may yet fill the sky beyond our windows—has in fact arrived.
[Img[Images/aspencatkins_20110410T133258_IMG_9792_small.JPG]]
Aspen catkins in the wind. Photo by Jeremy D. Rogers
Aspen catkins, which emerge before leaves appear, are cylindrical in shape and fuzzy, with feather-like tufts of hair adorning numerous tiny seeds. Their fluffy appearance is endearing. But it is the fate of the catkins that really captures the imagination, tempting us to look ahead to the future. What will become of this fuzzy little thing?
Aspens, of which there are three species—the American quaking aspen (//Populus tremuloides//), the American big-tooth aspen (//P. grandidentata//), and the European aspen (//P. tremula//)—exhibit several curious traits when it comes to reproduction. For example, each tree is either male or female, a condition known as dioecism, and while both male and female aspens produce catkins, only the male catkin has pollen, which is transferred to a female by the wind. And when the right breeze comes along in early summer, the pollinated female will release her seeds, which parachute along through the air, swept away to some distant place.
Aspens have a low rate of reproductive success. Indeed, it takes trillions of seeds being dispersed on the wind each year to ensure that a percentage sufficient for species propagation happens to parachute into a suitable environment, where they can germinate and sprout. Reproductive success is limited in part because aspens have strict germination constraints. For example, aspens are shade-intolerant, and therefore a seed needs a sunny spot to grow. That spot also must be free from seed-eating animals and able to retain moisture.
Another constraint on reproduction actually is imposed prior to pollination and has to do with the distance between male and female trees. Each aspen grove is a clone, meaning that all the trees in a grove are identical to the founder sapling. Hence, if a female sapling happened to give rise to the grove, all the individual trees in the grove will be female. This means that pollination can occur only if groves of the opposite sex are relatively close to one another. If they are separated by too great a distance, pollination between them is unlikely.
The future of each species of aspen hinges on its tufted catkin seeds, new generations of which face the perilous wind-borne journey every spring. Most do not make it. The ones that do, however, spawn entire groves of aspens—stands of trees that may survive for hundreds or possibly thousands of years.
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//This post originally appeared in Naturephiles on ~TalkingScience.org and was republished on the [[Britannica Blog|http://www.britannica.com/blogs/2011/08/exotic-birdofparadise-flower/]].//
The bird-of-paradise flower, so-named for its remarkable bird-like appearance when in bloom, is a favorite among horticulturists and can be found growing in gardens worldwide. In the wild, however, the plant’s range is limited to the subtropical coastal thickets of South Africa, between ~KwaZulu-Natal province in the southeast and the south-central Eastern Cape province.
The bird-of-paradise, or crane, flower (//Strelitzia reginae//) was discovered in 1772-73 by Scottish botanist Francis Masson, who worked for the Royal Gardens at Kew. At the time, Masson was on a plant-hunting expedition in South Africa, and throughout his journey he sent hundreds of specimens, one of which was the bird-of-paradise, to the gardens. In 1773 English botanist Sir Joseph Banks, who was then serving as the unofficial director of the Kew Gardens, introduced the plant to Britain. He named it Strelitzia after Charlotte of ~Mecklenburg-Strelitz, queen consort of George III.
The bird-of-paradise is classified in the order Zingiberales, a group of flowering plants containing ginger, banana, and their relatives. Members of this order are grouped together in part because they are monocots—their embryos have only a single cotyledon, or seed leaf (dicots, the other major group of flowering plants, have two cotyledons). Monocotyledonous plants also characteristically have trimerous (three-part) flowers and parallel-veined leaves (in contrast to the net-like and crossing reticulate veins of dicotyledonous plants).
The bird-of-paradise grows to about 3 ½ to 4 feet in height and has clumps of stiff bananalike leaves, gray to green in color, extending up from its base. Its flowers emerge from a beak-like structure known as the spathe, which sits horizontally at the top of a long stalk and forms a sheath that protects the flower. The color of the spathe ranges from green to purple.
Flowers typically appear in mid-winter and open in succession, with the first ones opening in spring. Each flower consists of three orange upright sepals and three blue petals. Located at the base of the flower where two of the petals join together is the nectary, a nectar-secreting organ. When birds such as the amethyst sunbird (//Nectarinia amethystina//) and the lesser double-collared sunbird (//Cinnyris chalybeus//) land on the flower to drink the nectar, the petals open and pollen becomes attached to the birds’ feet.
Pollination is complete when birds transfer pollen from one bird-of-paradise flower to another. The seeds that form following fertilization give rise to small fruits, which eventually split open, exposing the seeds. The seeds are eaten by birds, which scatter them in new areas, thereby helping the plant maintain its distribution across its habitat. Seeds are often collected by horticulturists for plant cultivation. Because the plant is so widely cultivated, seeds generally are gathered from cultivars, rather than from plants in the wild.
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//The following was originally published in Naturephiles on ~TalkingScience.org.//
Fin whales are enormous animals, with the largest individuals measuring nearly 90 feet in length and weighing 80 tons. Something that large should be conspicuous, especially in the coastal waters where fin whales spend much of their time. But the species’ propensity to disperse to open water and steep declines in its numbers in the 20th century have rendered it a rare sight. And so, relative to its famous baleen cousins, the blue whale and the [[humpback|Humpback whale]], the fin whale is lesser known, and its behavior little understood.
Fin whales (//Balaenoptera physalus//) are large from birth. In the last couple months of gestation, in one of the fastest fetal growth spurts known to animals, they more than double in size, growing to about 21 feet and two tons by the time they are born. Within five or six years, most fin whales have reached their adult size, and their distinguishing features have become pronounced. These features include a prominent ridge that stretches from the tip of the upper jaw to the blowhole, a pointed or hooked dorsal fin, and a sharp ridge that runs along the top edge of the lower back.
Fin whales also have remarkably long and trim bodies, which contrast with the stockier build of blue whales and humpbacks. In fact, although some blue whales may weigh more than twice as much as the largest fin whales when full-grown, blue whales are about the same length as or only slightly longer than fin whales. The latter's slender, hydrodynamic profile allows it to explode in bursts of speed of as many as 25 knots, making it one of the fastest whales in the world. That speed is especially useful for feeding, when a rapid lunge into a school of prey, with mouth wide open, allows for the swift intake of food.
While fin whales feed primarily on krill, they also enjoy small fish, such as capelin, herring, and sandlance. Like some other whales that feed on schooling fish, fin whales will circle their prey to encourage the fish to gather into a tight group. They then lunge into the school with mouth agape, engulfing both fish and water. The whales' baleen filters the water, trapping the fish in the mouth.
Although it is not known with certainty, fin whales may also make use of their asymmetrical coloration when feeding. The asymmetry affects the lower right and left jaws, with the right side being gray or white and the left black or dark brown; this coloration is repeated in the fin whale's baleen. When lunging on a school of fish from above, fin whales may do so on their right sides, thereby showing the white jaw to their prey and thus blending in with light from the sky above. This may confuse the fish just long enough to allow the whales to capture a larger quantity than they would otherwise.
Fin whales inhabit the world’s major oceans but occur most frequently in temperate and polar waters. But relatively little is known about their movements. For instance, while they occur over a wide range of latitudes throughout the year, suggesting that they do not migrate, some groups appear to move into winter or summer ranges occupied by other groups within their latitudinal range. Tracking the movements of fin whales is made difficult by their tendency to swim alone or in small groups dispersed over large areas and by their occasional mingling with blue whales.
For much of its coexistence with whaling vessels piloted by humans, the fin whale's greatest asset has been its speed. But with the appearance of faster vessels and stronger harpoons in the 20th century, fin whales could no longer escape man. The result was the persecution of the species, to near extinction, particularly in the Southern Hemisphere.
Today the fin whale is listed as endangered. But while populations in [[Antarctica|Antarctica]] still suffer low numbers, those in the North Atlantic appear to be recovering, aided in part by the female fin whale's ability to bear offspring every two or three years for the greater part of her 80-year-long life.
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//The following was originally published on [[ScienceFriday.com|http://www.sciencefriday.com/blogs/10/25/2011/the-flight-of-the-bumblebee-bat.html?series=2]].//
In the dark depths of a limestone cave in Sai Yok National Park, a tiny bat hangs effortlessly from the ceiling, resting, waiting for sunset, when it will take flight and embark on its nightly foraging expedition. It will not be out for long—indeed, this bat, the bumblebee bat (//Craseonycteris thonglongyai//), needs only a few small insects to satisfy its appetite. It is, after all, a mere two grams in weight and a little over an inch in length, making it one of the world’s smallest mammals.
The bumblebee bat is also known as the hog-nosed bat or Old World hog-nosed bat. Both names reflect the bat’s other distinguishing trait, a fleshy pig-like snout. The “Old World” name also alludes to the part of the world it inhabits. Its true range in the Old World, however, extends only from southern Myanmar to west-central Thailand, which is the site of Sai Yok park.
Within its range, the bumblebee bat spends much of its time hidden in limestone caves along rivers on the edges of bamboo and deciduous forests. Its red-brown to gray color helps it blend seamlessly into the background of its cave habitat. It flies only under the cover of darkness in the dense forests, where it is but a fleeting shadow in the night. Such secretive behavior would suggest that bumblebee bats are avoiding predators. But exactly what predators the bats are evading remains unknown.
In fact, there is much about the bumblebee bat that has yet to be described. For example, little is known about their reproductive behavior and whether colonies move from one cave to another. What is known, is that like most other types of bats, the bumblebee bat navigates and locates prey by emitting high-pitched sounds that bounce off objects and reflect back to its ears. This process, known as echolocation, provides the bat with different types of information, such as variations in loudness, time delay from when a pulse of sound was emitted and returned, and time differences in the return of sound to the two ears. From this information, they are able to detect the precise location, orientation, and type of prey they encounter.
The bumblebee bat’s remote cave sites would suggest that the species is safe from potentially threatening human activities. But since its discovery in the 1970s by Thai mammologist Kitti Thonglongya (for whom it is sometimes referred to as Kitti’s hog-nosed bat), the species has been in decline. According to the IUCN Red List of Threatened Species, colonies at some cave sites decreased by 10 percent between 1983 and 1997 and by an estimated 14 percent between 1998 and 2008. In fact, there are now fewer than 10,000 bumblebee bats left in the wild, and populations in Thailand are expected to decrease by another 10 percent in the next decade.
Major threats to the existence of the bumblebee bat stem from human activities and include, for example, human intrusion into caves from tourism and religious pilgrimages and habitat destruction from mining and the burning of forests around cave entrances. Many of these activities suggest that people are unaware of the bat’s presence or the impact of their own presence. So, as part of efforts to save the tiny creature, conservationists must now work to improve public education and awareness. Along with scientific study, education and awareness will better equip the public and scientists with the knowledge they need to ensure the bumblebee bat’s protection.
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//This post was originally published in my column [[NaturePhiles|http://www.talkingscience.org/category/naturephiles/]] on [[Talking Science|http://www.talkingscience.org/2012/01/the-impact-of-rising-ocean-carbon-levels-on-fish-behavior/]].//
The continued increase of atmospheric carbon suggests that by the end of this century the world’s oceans, which absorb 25 percent of our carbon dioxide emissions, could contain twice as much of the greenhouse gas as they do now. Such a steep rise could have significant impacts on some species of marine fish, since the introduction of more carbon dioxide turns seawater acidic and dramatically alters the animals’ sensory response -- changes that a [[new report|http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate1352.html]] published in the journal //Nature Climate Change// indicates are mediated by a chemical receptor in the brain known as ~GABA-A.
Since the late 1990s, scientists have known that ocean acidification alters seawater carbonate and aragonite chemistry, which affects the calcification and deposition of shell and skeletal materials in marine invertebrates such as corals and shellfish. In the last several years, however, scientists have also discovered that high seawater carbon dioxide levels, equivalent to those expected at the end of the century, affect fish. Among the behavioral changes observed thus far are disruption of hearing and smell (olfaction) in juvenile [[orange clownfish|Orange clownfish]] (//Amphiprion percula//) and of lateralization (favored turning direction) in yellowtail demoiselles (//Neopomacentrus azysron//).
[img[Images/Amphiprion_percula_sm.JPG]]
The orange clownfish, //Amphiprion percula//.
In fish, high carbon levels in water can cause acidosis (excessive acid in body fluids), a potentially life-threatening condition. Fish try to overcome acidosis through acid-base regulation and the accumulation of bicarbonate, which neutralizes acids and thereby prevents body fluids from becoming too acidic. But as the new study, conducted by a team of scientists from Australia, Italy, and Norway, has shown, this process reverses the normal function of the ~GABA-A receptor.
In the vertebrate brain, the ~GABA-A (gamma-aminobutyric acid-A) receptor is inhibitory, acting to attenuate the transmission of chemical signals between neurons. This occurs when chloride ions, and to a lesser extent bicarbonate ions, flow through the receptor and into the cell in response to some external signal. When intracellular chloride and bicarbonate concentrations become too high, the reverse happens -- the receptor conducts the ions out of the cell. By doing so, however, the inhibitory effect is lost, and the neurons become excitable. In the study, the scientists hypothesized that this reversal in receptor activity was responsible for the observed changes in sensory behavior in juvenile fish.
To investigate their hypothesis, the scientists reared larval clownfish in either control or high carbon environments and determined the effects of carbon on olfactory responses. Controls (fish raised in a carbon environment similar to that currently found in the ocean) avoided water trails that contained the odor of blue-spotted rockcod (Cephalopholis cyanostigma), a clownfish predator. Fish exposed to high carbon levels, however, were drawn to the odor. This abnormal response was corrected when gabazine, a chemical that blocks the ~GABA-A receptor, was added to the water.
In another series of experiments, the team investigated lateralization as a measure of brain function in yellowtail demoiselles. They collected wild yellowtails and exposed them to either control or high carbon environments and then recorded observations of turning direction in a T-shaped maze. Under normal conditions, yellowtails show a preference for turning left or right that is greater than expected by chance. Following exposure to large amounts of carbon, however, the researchers found that the fish turned at random. Similar to the abnormal olfactory responses in clownfish, the atypical lateralization effect in yellowtail demoiselles was corrected by gabazine.
Because gabazine binds only to ~GABA-A receptors, the findings indicate that carbon dioxide interferes with normal ~GABA-A activity and that this interference produces the behavioral abnormalities observed in coral reef fish. The existence of ~GABA-A receptors in the brains of vertebrates and invertebrates suggests that increasing carbon dioxide levels in the atmosphere and ocean could have effects across a variety of ecosystems. These effects, however, likely are to be most pronounced in aquatic ecosystems, because carbon dioxide is far more soluble in water than oxygen and because aquatic species tend to have relatively low carbon dioxide levels in their blood.
The researchers suspect, however, that because water-breathing species use different strategies to cope with high acidity, only certain groups of aquatic life may be susceptible to the effects of increasing carbon levels in seawater. The most vulnerable groups would include those species that rely almost exclusively on acid-base regulation, such as teleosts and crustaceans, and species that have unusually high rates of oxygen consumption, such as coral reef fish larvae and pelagic fish.
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See also [[Oceans|Oceans]]
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//The following was originally published in Naturephiles on ~TalkingScience.org (later moved to [[ScienceFriday.com|http://www.sciencefriday.com/blogs/12/20/2011/the-life-of-the-least-weasel.html?series=2]]).//
With a black button nose, large round eyes, and fuzzy knobs of ears, the least weasel is undoubtedly adorable. And it is made all the more so by its small size, with the tiniest individuals weighing just 25 grams and measuring a mere four inches in length. But beneath the fur and the lanky little profile lies a fierce meat-hungry predator, a bantamweight killer that carries a reputation as the world's smallest carnivore^^1^^.
The least weasel (//Mustela nivalis//) has an appetite for rodents and other small mammals but will also prey on lizards, birds' eggs, chicks, and small amphibians, such as frogs and salamanders. In some instances, aided by their deftness and determination, they will attack rabbits and other mammals that are relatively large. The type of prey taken by least weasels depends mainly on seasonal and geographical factors, which determine the abundance of prey animals, particularly voles, lemmings, mice, and shrews.
Least weasels enjoy a wide distribution, inhabiting much of Europe, North Africa, Asia, and the northern region of North America. They are also found on New Zealand, on a small handful of Japanese islands, on São Tomé off central Africa, on the Portuguese archipelago of the Azores, and on several Mediterranean islands. The species, however, is not native to the majority of these islands.
Within its geographical range, the least weasel occupies a variety of habitats. For instance, while it often lives in boreal forests, where it benefits from dense tree cover and understory that conceals it from its predators, it is also found in meadows and prairies and in scrubby and even semi-desert areas. In each of these habitats, it commonly makes its home in burrows or dens abandoned by other small animals.
In winter, the least weasel’s fur is transformed from a rich brown with white underbelly and feet to completely white with a few black hairs adorning the tip of its tail. This conversion is most thoroughly effected in the northern reaches of its distribution, where fading into the pale backdrop of snow-covered landscapes is not simply an art but a skill for survival. Indeed, its white coat conceals it from prey and predator alike, enabling it to blend in with the snow as it tunnels close to its quarry before a kill and to hide from its greatest adversaries—birds of prey circling in the air or perched in trees high above. Least weasels’ survival in winter is aided further by their habit of creating food stores, which can see them through even the harshest of freezing weather.
The reproductive behavior of the least weasel differs from that of many mustelids (the common name given to members of the family Mustelidae, which includes weasels). Indeed, some mustelids, including badgers, martens, and wolverines, exhibit delayed implantation, in which fertilized embryos produced from a mating that occurred in late summer or fall do not attach to the uterine lining and begin to develop until spring. Delayed implantation helps ensure that offspring will be born under favorable conditions, such as when food resources are plentiful and the weather is warm. It also limits the number of litters produced per year to just one. In contrast, least weasels do not experience delayed implantation, and they have a brief gestation period (34 to 37 days). Hence they are able to produce two litters of offspring in a single year.
The least weasel’s robust reproductive activity has helped it maintain apparently viable populations, despite threats such as loss of habitat to logging and agriculture and exposure to poisonous substances, including rodenticides. But it will not be able to endure such pressures for very long. Its short life span, just 1 to 2 years in the wild, leaves the species susceptible to swift declines. Populations in Europe are already deteriorating, and it is now only rarely seen in certain other areas of its native range.
^^1^^The northern short-tailed shrew (//Blarina brevicauda//), which weighs about 20 to 22 grams and measures three to four inches in length, also eats small animals; however, it also eats seeds and other plant plants and therefore is not strictly carnivorous.
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//The following was originally published in Naturephiles on ~TalkingScience.org.//
Badwater Basin in Death Valley sits 282 feet below sea level and is known for its extensive salt flats and brackish water. The harsh environment is forbidding to all but the specially adapted and salt-tolerant. And in its collection of atypical life-forms is a group of greigite-producing magnetic bacteria, which were first isolated from a sample of brackish spring water and were described in [[a report|http://www.sciencemag.org/content/334/6063/1720.abstract]] published in //Science//.
Magnetic bacteria orient and navigate along magnetic fields and are guided in their movements by intracellular organelles known as magnetosomes, of which there are two types—those that contain nanocrystals of the iron-oxide mineral magnetite (Fe~~3~~O~~4~~), and those that contain crystals of the iron-sulfide mineral greigite (Fe~~3~~S~~4~~). The magnetosomes form chains along the cell's plasma membrane and are fixed into a permanent magnetic dipole. The strength of the magnetic dipole (the magnetic dipole moment) is such that the entire organism is always oriented along the geomagnetic field, switching its orientation only when a stronger field is applied. Magnetic bacteria have one of two polarities, North or South, which is dictated by the orientation of the magnetic dipole.
The Badlands microorganisms are unique from most previously known magnetic bacteria in that they contain both magnetite and greigite magnetosomes, as opposed to just one or the other. The proportion of the two magnetosomes varies with the chemical features of the environment. For example, when hydrogen sulfide is allowed to accumulate in the bacterial growth medium, the predominant magnetosomes are greigite-producing. When hydrogen sulfide concentrations decrease, the cells contain primarily magnetite-producing magnetosomes. The ability to switch between the two forms of biomineralization may be the result of two different magnetosome gene clusters—one for magnetite and one for greigite—that occur in the organism's genome.
The //Science// study demonstrated that the greigite-producing bacteria can thrive in an anaerobic environment with a liquid medium for sulfate-reducing bacteria. Hence, sulfate appears to be an environmental factor that determines whether the bacteria produce greigite. This observation indicates that the organisms constitute a group of sulfate-reducing bacteria, which phylogenetic analyses placed within the class //Deltaproteobacteria//.
//Deltaproteobacteria// also contains a group of greigite-producing multicellular prokaryotes known as many-celled magnetotactic prokaryotes, or ~MMPs. ~MMPs are obligately multicellular and consist of 10 to 60 genetically identical cells, shaped into a hollow ball. The cells reproduce together, with all the individual cells dividing at the same time; when a cell is removed from the MMP, it dies. Despite their differences in cellular behavior, ~MMPs and the Badlands microogranisms both exhibit motility in response to magnetic fields, under the direction of greigite magnetosomes.
The greigite-producing bacteria could have impacts in nanotechnology and biotechnology. Magnetite, for example, is being explored for various applications, such as the development of novel drug delivery systems. Similar investigations for greigite had been delayed in part by the lack of a biological source that could be grown in culture.
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[[Pronghorn|Pronghorn]] (//Antilocapra americana//) are ridiculously fast, reaching speeds of more than 80 or 90 km/hr. Cheetahs, by comparison, can sprint in excess of 100 or 110 km/hr. But pronghorn also have remarkable stamina, sustaining speeds of about 60-65 km/hr over long distances—something the cheetah cannot do. With no predators even nearing the pronghorn's speed, we have to ask: why is the pronghorn so fast? The best explanation proposed to date is that the pronghorn is running from the shadows of extinct predators.
Learn more about the pronghorn's remarkable running ability:
[[The Pronghorn of North America: Running from the Past|http://www.talkingscience.org/2011/10/the-pronghorn-of-north-america-running-from-the-past/]]
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//The following was originally published in Naturephiles on ~TalkingScience.org (later moved to [[ScienceFriday.com|http://www.sciencefriday.com/blogs/01/17/2012/the-tiny-frogs-of-papua-new-guinea.html?series=2]]).//
Lilliputian life is all around us -- in trees and water, or as a team of U.S. scientists [[reported|http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0029797]], in leaf litter on the forest floor. Indeed, it was beneath the leaves in the lowland rainforests of eastern Papua New Guinea where they discovered two new species of tiny frogs. The most diminutive of the two, at 7 to 8 mm in length, claims the title of world’s smallest vertebrate, and its discovery raises intriguing questions about the limits of extreme body size.
The record-setting species is known as //Paedophryne amauensis//, and before it came along, the world’s largest and smallest vertebrates, the blue whale and the fish //Paedocypris progenetica//, respectively, were both aquatic. This relationship suggested that perhaps there was something about the buoyancy of water that supported the survival of animals with extreme body size. And while there still might be something to that hypothesis, the new frog is terrestrial, indicating that for tiny creatures at least, there is more to survival than a buoyant buffer of water.
The team’s report, published in the journal //~PLoS ONE//, also describes the discovery of a second new species, //Paedophryne swiftorum//, which is a microhylid (small frog) that measures about 8 to 9 mm in length. The researchers determined that the two frogs were in fact separate species, and were different from the other two members of //Paedophryne// (//P. kathismaphlox// and //P. oyatabu//), using morphological, ecological, and genomic analyses. (//P. kathismaphlox// and //P. oyatabu// were reported in 2010 and are also found in eastern Papua New Guinea.)
Through genetic comparisons with other species in the family Microhylidae, to which the genus //Paedophryne// belongs, the scientists also were able to establish the new species’ evolutionary relationship with other small frogs. A major finding of the comparisons was the evolutionary divergence of //Paedophryne//, which indicated that the extremely small frogs had appeared early on in the evolution of New Guinea microhylids. Hence, the tiny creatures have been hiding in the rainforests there for a very long time. While their small size certainly made it easy for them to hide, they likely also managed to escape human notice for so long because the high-pitched calls that they make sound remarkably similar to those of stridulatory insects (such as katydids and crickets).
Based on the amount of calling by //P. swiftorum//, the researchers estimate that the frogs may occur relatively close to one another within the leaf litter, and thus they may be fairly common in the East Papuan Aggregate Terrain of the Papuan Peninsula (eastern Papua New Guinea). Their density and ecological position, as predator of small invertebrates and prey of larger animals, indicates that they fulfill an important role within the Papuan rainforest ecosystem.
The rich biodiversity of the Papua New Guinea rainforests suggests that there may even be other species of frogs awaiting discovery. For now, however, given that approximately 32 percent of amphibians worldwide have gone extinct or at high risk of doing so soon, simply knowing of the existence of the //Paedophryne// species and that they may be abundant within their habitat is encouraging.
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//The following was originally published in Naturephiles on [[ScienceFriday.com|http://www.sciencefriday.com/blogs/04/03/2012/the-victory-squawk-of-the-little-blue-penguin.html?series=2]].//
Victory is sweet, so much so that we often feel compelled to rejoice with a cry of triumph. For some animals, that cry not only announces a win to all those within earshot but also serves surprisingly complex social functions. Take, for instance, the call of the victorious little blue penguin (//Eudyptula minor//), which a [[study|http://www.sciencedirect.com/science/article/pii/S0003347211005240]] in the journal //Animal Behavior// revealed has a direct effect on the behavior of "social eavesdroppers" -- penguins who, from the safety of their burrows, assess the quality of fighting individuals based solely on their vocalizations.
Male little blue penguins are fierce defenders of their territories and frequently become engaged in flipper-slapping territorial disputes. At the conclusion of a scuffle, the winner celebrates with a so-called triumph display, in which he delivers a victory bray -- a distinctive squawk that according to the new study serves as a sort of warning signal to other males in the colony, potentially mitigating future confrontations for the winner and preventing embarrassing defeats for lesser male challengers.
Little blue penguins, which are the smallest penguins in the world, are social animals that use vocalization during activities such as courtship and foraging and as a way of announcing their arrival at their home burrows. However, while much is known about the various functions of many of the penguins' calls, the social significance of vocalization associated with victory calls had remained unclear.
To assess the impact of triumph brays on the behavior of eavesdropping penguins, the scientists played a recording of a vocal exchange and flipper-slapping fight between territorial males and then played recordings of both the victor's triumph call and the loser's call. They then measured the heart rates of eavesdroppers in response to the sounds using heart monitors hidden in artificial eggs that were placed in the penguins' nests. The team found that eavesdropping males' heart rates increased in response to the victor's call when compared with the loser's call. In addition, in simulated approach experiments in which the loser's or winner's call was played just outside the entrance of an eavesdropper's burrow, the scientists discovered that eavesdropping males challenged the loser's call with vocalizations of their own but fell silent when the triumph call was played.
Triumph displays and other forms of postconflict signaling have been documented in a variety of species, including birds such as the Canada goose (//Branta canadensis//), the greylag goose (//Anser anser//), and the bell shrike (//Laniarius aethiopicus//), as well as animals such as the green frog (//Rana clamitans//) and an insect known as the Wellington tree weta (//Hemideina crassidens//). Postconflict signaling in these species appears to function either as a form of advertising, in which the winner's display communicates his dominance to eavesdroppers, or as a form of intimidation, in which the winner's display serves to reduce the chance that the loser will initiate a future challenge. Thus, in many ways, by showing off a little after a victory, these animals are simply establishing their reputation as winners. In other words, they're behaving very much like humans.
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CV can be made available upon request (contact me: kerogers (at) nasw.org). Freelance rates determined on a per project basis.
''Education'':
Ph.D. in Pharmacology/Toxicology, minor in Cancer Biology, University of Arizona (2006)
B.S. in Biology, minor in Chemistry, Midway College (2001)
''Author of'':
//[[The Quiet Extinction: Stories of North America’s Rare and Threatened Plants|http://www.uapress.arizona.edu/Books/bid2541.htm]]// (University of Arizona Press, 2015)
//[[Out of Nature: Why Drugs from Plants Matter to the Future of Humanity|http://www.outofnature.net/]]// (University of Arizona Press, 2012) (Read a review here: [[Journal of Ethnopharmacology|Images/ethnopharm_bookreview_outofnature.pdf]])
''Some writing and editing samples'':
''Magazine'':
Saving Steps: On the March to End Amputation ([[Temple Health Magazine, Spring 2015|http://issuu.com/templehealth/docs/thmagazine_spring2015?e=3002455/2634927]])
Epigenetic Therapy: A Sea Change for Cancer? ([[Temple Health Magazine, Spring 2015|http://issuu.com/templehealth/docs/thmagazine_spring2015?e=3002455/2634927]])
''News'':
Temple University
[[Researchers Identify Brain Areas Activated by Itch-Relieving Drug|http://www.temple.edu/medicine/temple_research_identifies_brain_areas_activated_by_itch_drug.htm]] (Sept. 22, 2014)
[[Temple Scientists Studying Mitochondrial Calcium Handling Yield New Disease Targets|http://www.temple.edu/medicine/mitochondrial_calcium_handling.htm]] (Dec. 12, 2013)
[[Youthful Stem Cells from Bone Can Heal the Heart, Raising Hope for New Heart Therapies, Temple Scientists Report|http://temple.edu/medicine/bone_stem_cells_heal_heart.htm]] (Sept. 5, 2013)
[[Clues to heart disease in unexpected places, Temple researchers discover|http://www.temple.edu/medicine/clues_to_heart_disease.htm]] (April 15 2013)
/%[[Temple Surgeon Working to Bring New Stent for Aortic Aneurysm to University Hospital Patients|http://www.temple.edu/medicine/multilayer_stent_technology.htm]] (Jan. 27, 2014)
[[Temple Research on Bone-Derived Stem Cells that Repair Heart Tissue Gains Interest|http://www.temple.edu/medicine/bone_stem_cells_repair_heart.htm]] Dec. 5, 2013)
[[Temple's Steven Houser, PhD, FAHA, Recognized by the American Heart Association for Career Contributions to Cardiovascular Research|http://www.temple.edu/medicine/houser_aha_awards.htm]] (Nov. 20, 2013)
[[Breakthrough by Temple Researchers Could Lead to New Treatment for Heart Attack|http://www.temple.edu/medicine/protein_research_tnni3k.htm]] (Nov. 6, 2013)
[[Temple scientists weaken HIV infection in immune cells using synthetic agents related to active ingredient in marijuana|http://www.temple.edu/medicine/hiv_immune_cells.htm]] (May 1, 2013)%/
Northwestern University Newscenter
[[Northwestern Writers Helps Local Teens Get Creative|http://www.northwestern.edu/newscenter/stories/2008/08/writing.html]] (August 2008)
[[iLABS Network Gives ETHS Students Ability To Do Advanced Research Remotely|http://www.northwestern.edu/newscenter/stories/2008/08/ilabs.html]] (August 2008)
University of Arizona News
[[Nerve Cells' Power Plants Caught in a Traffic Jam|http://uanews.org/node/11470]] (August 2005)
[[Lehmann Lovegrass Won't Succumb to Fire|http://uanews.org/node/9890]] (August 2004)
[[Can We Restore Wetlands And Leave The Mosquitoes Out?|http://uanews.org/node/9713]] (May 2004)
''Scientific Journals'':
Rogers, Kara, and Gilbert M. Lenoir. [[Cancer research in France|http://onlinelibrary.wiley.com.ezproxy.library.wisc.edu/doi/10.1002/ijc.29131/full]]. //Int. J. Cancer// Published online 14 Aug. 2014. DOI: 10.1002/ijc.29131
Freelance, //International Journal of Cancer// (2012-2015).
''Books'':
Editor of [[more than 20 books|http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dstripbooks&field-keywords=KARA+rogers+rosen&x=0&y=0]] for Rosen Educational Publishing and Britannica Educational Publishing.
Collaborated with Constable & Robinson Publishing, London, on //The Britannica Guide to the Brain// (2008) and //The Britannica Guide to Genetics// (2009).
''Blogs'':
Scientific American Guest Blog:
[[Epigenetics: A Turning Point in Our Understanding of Heredity|http://blogs.scientificamerican.com/guest-blog/2012/01/16/epigenetics-a-turning-point-in-our-understanding-of-heredity/]]
[[Machine Counterpart: Nature’s New Creatures|http://blogs.scientificamerican.com/guest-blog/2012/05/08/machine-counterpart-natures-new-creatures/]]
[[The Legacy of Lifestyle|http://blogs.scientificamerican.com/guest-blog/2013/03/27/the-legacy-of-lifestyle/]]
/%[[Bee Brain Plasticity: Turning Back the Clock on Aging|http://blogs.scientificamerican.com/guest-blog/2012/07/11/bee-brain-plasticity-turning-back-the-clock-on-aging/]]
[[Authenticating Cells Out of Curiosity, Not Fear|http://blogs.scientificamerican.com/guest-blog/2012/11/26/authenticating-cells-out-of-curiosity-not-fear/]]%/
''Other'':
Field Museum, Chicago:
For //In the Field// magazine, winter 2007: [[Q&A interview with Michael O. Dillon on the George Washington Carver exhibition|http://www.archive.org/stream/infieldbulletino79fiel#page/6/mode/2up/search/rogers]].
Press coverage, 2012 American Association of Cancer Research conference, Chicago:
[[Novel PI3K Inhibitors Enter Human Studies|http://cancerdiscovery.aacrjournals.org/content/2/5/OF3.full?sid=b1831d48-32b9-40b7-abc0-899e6834997b]]. //Cancer Discovery// May 2012 (online 4 April 2012).
Press coverage, 2012 American Society of Clinical Oncology conference, Chicago:
[[Anti-PD-1 Drug Shows Strong Promise|http://cdnews.aacrjournals.org/node/13803]]. //Cancer Discovery// 7 June 2012
[[Finding Your Place in Cancer Research|http://cancerdiscovery.aacrjournals.org/content/early/2012/06/20/2159-8290.CD-NB2012-063.full?sid=a6905dcd-5780-4c5c-b28c-5bbdcae60a02]]. //Cancer Discovery// 21 June 2012.
[[Author of numerous articles |http://www.britannica.com/bps/user-profile/6713/Kara-Rogers]] in the //Encyclopaedia Britannica//.
/%''The writer in the press'':
Guarino, Mark. [[Kentucky Derby 2011: Drug use questions hang over US horse racing|http://www.csmonitor.com/USA/Sports/2011/0507/Kentucky-Derby-2011-Drug-use-questions-hang-over-US-horse-racing]], //The Christian Science Monitor//. 7 May 2011.
Rudnicki, Alicia. [[Lemonade While Pregnant|http://www.livestrong.com/article/527611-lemonade-while-pregnant/]], //Live Strong.com//. 1 Sept. 2011.
[[What is Listeria and How do you protect yourself|http://averagepersongardening.blogspot.com/2011/09/what-is-listeria-and-how-do-you-protect.html]], //Mike the Gardener//. 20 Sept. 2011.
Rudnicki, Alicia. [[How to Build Endurance When Running for the Mature Menopausal Woman|http://www.livestrong.com/article/550998-how-to-build-endurance-when-running-for-the-mature-menopausal-woman/]], //Live Strong.com//. 9 Nov. 2011.%/
/%Rogers K and Meaney FJ. “Eugenics.” In: Sarah Boslaugh, editor. //Encyclopedia of Epidemiology//. SAGE Publications, 2008.
Rogers K. “"""Vector-Borne Disease""".” In: Sarah Boslaugh, editor. //Encyclopedia of Epidemiology//. SAGE Publications, 2008.
Ahrens K, Rogers K, Feuerbacher O, """Prue-Owens""" K, Currie J, and Meaney FJ. “History of genetics.” In: H. James Birx, editor. //Encyclopedia of Anthropology//. SAGE Publications, 2006.
Rogers K and Meaney FJ. “Biological anthropology and neo-Darwinism.” In: H. James Birx, editor. //Encyclopedia of Anthropology//. SAGE Publications, 2006.%/
/%[[Naturephiles|http://sciencefriday.com/blogs/?series=2#page/posts/1]]
[[Science Up Front|http://www.britannica.com/blogs/category/science-up-front/]]
[[Profile and posts|http://www.britannica.com/blogs/author/krogers/]] for the Britannica Blog%/
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//The following was originally published in Naturephiles on ~TalkingScience.org (later moved to [[ScienceFriday.com|http://www.sciencefriday.com/blogs/02/07/2012/trouble-in-paradise-mosquitoes-disease-and-hawaii-s-native-forest-birds.html?series=2]]).//
The southern house mosquito (//Culex quinquefasciatus//) arrived in Hawaii in the 1820s, its larvae likely entering the local water supply when contaminated water casks aboard a sailing vessel were dumped at the port of Maui. Up to that time, mosquitoes had been nonexistent on the islands, and hence native birds had evolved in environments without mosquito-borne disease, leaving them with no innate defense against infection. As a result, the arrival of avian pox (in the 1800s) and avian malaria (in the early 1900s), both of which are transmitted by //Culex// and presumably reached the islands in nonnative birds transported on ships, facilitated the near decimation of Hawaii’s forest birds.
Avian pox is a viral disease that in addition to being transmitted by mosquitoes, can be passed to uninfected birds through physical contact with infected individuals, contact with contaminated surfaces, or ingestion of contaminated food or water. Infection produces wart-like growths in areas of skin that are unprotected by feathers, such as around the eyes and on the beak, potentially impairing vision or the ability to feed. In “wet” pox, the growths form internally, in the mouth and throat or in the respiratory tract, causing difficulty with swallowing and breathing.
Avian malaria is a protozoal disease that in Hawaii is caused primarily by the species Plasmodium relictum, which is transmitted from infected to uninfected birds in the saliva of //Culex// mosquitoes. Following infection, the parasites go through two rounds of maturation, first in cells in the spleen and skin and then in macrophages (a type of white blood cell) in a variety of tissues, before invading and destroying red blood cells, which in susceptible birds can result in death from anemia. Birds that survive the acute phase develop chronic infection, in which parasites become encysted in tissues and cycle between dormant and active stages, sometimes causing periodic relapses of disease symptoms. Chronic infection also renders birds immune to reinfection with the same parasite.
[[Hawaiian honeycreepers|Hawaiian honeycreeper]], a group of songbirds that serves as a classic example of adaptive radiation (evolution into a wide variety of types, each with a specialized ecological role), have been the most heavily affected by avian pox and malaria. Since the time of captain James Cook’s first European discovery of the islands in 1778, disease and factors such as habitat loss, nonnative predators, and nonnative birds competing for habitat have led to the extinction of about one-third of the more than 55 known species of honeycreepers. These losses, combined with the loss of another third between the time when humans settled the islands (around 300 CE) and 1778, means that today, only 18 or 19 species are still alive. The majority of these are considered endangered or critically endangered.
Some of Hawaii’s native forest birds have found refuge from disease in high-elevation forests, which lie above the survival range of //Culex// mosquitoes. High-elevation forests, however, offer suboptimal habitat for species that evolved in lowland forests. In addition, climate change, and climate warming in particular, could allow //Culex// to migrate upslope, forcing the birds to move even further beyond the lowlands.
While the outlook remains bleak for many of Hawaii’s native forest birds, populations of some species have stabilized or are increasing, thanks in part to conservation efforts. Conservation successes include stable or growing populations of the bright orange Akepa (//Loxops coccineus//), the crimson-colored Apapane (//Himatione sanguinea//), and the yellow Kauai Amakihi (//Hemignathus kauaiensis//), all of which are honeycreepers. With increased awareness and improved understanding of species’ needs, and with a little help from birds that have been able to survive acute avian malaria, researchers are confident that other species can be rescued from the edge of extinction as well.
Back to [[Nature]]
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Turmeric (//Curcuma longa//), a herbaceous plant in the ginger family (Zingiberaceae), is perhaps best known as the source of curcumin. Curcumin displays a number of biological activities that are of particular interest for drug development. For instance, it [[has been found|http://clincancerres.aacrjournals.org/content/early/2011/08/05/1078-0432.CCR-11-1272]] to inhibit a cell signaling pathway involved in the development of head and neck cancer and to suppress the production of pro-inflammatory molecules in human saliva that are associated with the development of cancer.
Turmeric has long been used in traditional medicine in India and was the source of biopiracy complaints in the 1990s, when a team of researchers attempted to patent curcumin.
Back to [[Life]]
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I had the pleasure of exploring this immensely complex question for the Science Friday blog. Check it out [[here|http://www.sciencefriday.com/blogs/04/10/2013/will-there-be-another-ice-age.html?series=28]].
Back to [[Science]]
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