March 4, 2008, 6:11 PM CT

Two Kinds Of Carbon To Survive Coral Bleaching

How well ocean reefs recover from the growing damage caused by warming sea temperatures depends both on how much the tiny coral polyps can eat, and how healthy they can keep the microscopic algae that live inside their bodies.

New research intended to dissect one of the planet's most fertile and endangered ecosystems may change the way researchers look at this symbiotic partnership, shifting it from a case where the polyps function only as landlords to one where the tiny creatures actually nurture their algae.

Preliminary findings were presented today in two papers at the 2008 Ocean Sciences meeting in Orlando. The research focuses on the key role that carbon plays on the recovery of damaged coral reefs.

Andrea Grottoli, an assistant professor of earth sciences at Ohio State University, has spent the last 14 years studying two common forms of coral that populate the reefs near the Hawaii Institute of Marine Biology.

Two years ago, she reported that one of the corals she tested, Montipora capitata, or "rice" coral, was able to recover rapidly from bleaching because it increased its rate of feeding five-fold in comparison to how fast another form, Porites compressa, or "finger" coral, fed.

This strategy of gluttony enabled Montipora to survive the long-term damage that corals suffer when sea temperature climbs beyond the narrow 4 - 6 degree C range, where Porites might not......... Posted by: Janet      Read more         Source

March 4, 2008, 5:24 PM CT

National Zoo scimitar-horned oryx going into the wild

A male scimitar-horned oryx from the Smithsonians National Zoos Conservation and Research Center in Front Royal, Va., is playing an important role in ensuring the species does not vanish from the planet.

The oryx, along with eight others from American and European zoos, was sent to Tunisia in December 2007 for an eventual reintroduction into the wild, where they have been extinct since the late 1970s. Oryx are a type of desert antelope that are mostly white with reddish-brown necks and marks on the face and a long, dark, tufted tail. They stand up to 4 feet and 6 inches tall at the shoulder, and both male and female oryx have curved horns that grow to be several feet long.

Eventhough the animals have been returned to Tunisia, researchers cannot just simply release them into the wild. For now, the oryx are being kept in a 20,000-acre fenced area in the Dghoumes National Park. Within this protected zone, the five males and four females will reproduce and become acclimated to their arid surroundings. Once a sustainable population has been established, possibly a decade or so from now, the fences will come down.

Oryx were once common in the wild. As recently as 1900, there were as a number of as 1 million of them in North Africa. But their numbers began to dwindle as they were hunted, both for sport and food. To ensure that the same problems do not plague the oryx that are being reintroduced into the wild, the Tunisian government is planning conservation programs to educate local people about the importance of protecting the animals......... Posted by: Kelly      Read more         Source

March 3, 2008, 9:56 PM CT

Sleep patterns of Pigeons

In humans, as in all mammals, sleep consists of two phases: deep, dreamless slow-wave-sleep (SWS) alternates with dream phases, called Rapid Eye Movement (REM)-sleep. Although several studies suggest that information is processed and memories are consolidated during sleep, this remains a hotly debated topic in neurobiology. Comparative studies in birds may help to clarify the function of sleep by revealing overriding principles that would otherwise remain obscure if we only studied mammals. This is because birds are the only taxonomic group other than mammals to show both SWS and REM sleep. Interestingly, the independent evolution of similar sleep states in birds and mammals might be related to the fact that each group also independently evolved large brains capable of performing complex cognitive processes. In their actual study, researchers from the Max-Planck Institute of Ornithology in Seewiesen, Germany showed for the first time that birds compensate for sleep loss in a manner similar to humans (Journal of Sleep Research, Online-Publication February 27, 2008).

During SWS, the synchronous, slow oscillations of neurons are reflected in the EEG (Electroencephalogram), as large slow-waves with a frequency of less than 4 Hz, hence the name slow-wave sleep. The amount of slow-waves is positively correlated with the depth of sleep, and may reflect restorative processes occurring during sleep. Indeed, humans, and other mammals, recover from periods of sleep loss, primarily by increasing the amount of slow-waves, particularly during the first hours of SWS, in essence sleeping more intensely. Although birds also show SWS, it has been unclear whether they show a similar response to sleep loss. Dolores Martinez-Gonzalez and colleagues at the Max Planck Institute for Ornithology in Seewiesen found now, that birds - in this case pigeons - also do not simply shrug of sleep loss......... Posted by: Kelly      Read more         Source

March 3, 2008, 9:49 PM CT

Are wolves the pronghorn's best friend?

As western states debate removing the gray wolf from protection under the Endangered Species Act, a new study by the Wildlife Conservation Society cautions that doing so may result in an unintended decline in another species: the pronghorn, a uniquely North American animal that resembles an African antelope.

The study, appearing in the latest issue of the journal Ecology, says that fewer wolves mean more coyotes, which can prey heavily on pronghorn fawns if the delicate balance between predators and their prey is altered. As per the study, healthy wolf packs keep coyote numbers in check, while rarely feeding on pronghorn fawns themselves. As a result, fawns have higher survival rates when wolves are present in an ecosystem.

People tend to believe that more wolves always mean fewer prey, said WCS researcher Dr. Kim Berger, lead author of the study. But in this case, wolves are so much bigger than coyotes that it doesnt make sense for them to waste time searching for pronghorn fawns. It would be like trying to feed an entire family on a single Big Mac.

Over a three-year period, scientists radio-collared more than 100 fawns in wolf-free and wolf-abundant areas of Grand Teton National Park and monitored their survival throughout the summer. The results showed that only 10 percent of fawns survived in areas lacking wolves, but where coyote densities were higher. In areas where wolves were abundant, 34 percent of pronghorn fawns survived. Wolves reduce coyote numbers by killing them outright or by causing them to shift to safer areas of the Park not utilized by wolves......... Posted by: Kelly      Read more         Source

March 3, 2008, 9:21 PM CT

Low 2007 salmon returns along West Coast

NOAA researchers are reviewing unusual environmental conditions in the Pacific Ocean as the likely culprit for the dramatically low returns of Chinook and coho salmon to rivers and streams along the West Coast of the United States in 2007.

Scientists from NOAAs Northwest and Southwest Fisheries Science Centers are comparing data on the low food production of the California Current in 2005 that occurred when this years returning salmon would have been entering the ocean from their natal streams to feed and grow.

The cold waters of the California Current flow southward from the northern Pacific along the West Coast and are linked to upwelling, an ocean condition caused by winds that bring nutrients to the oceans surface and is the main source of nourishment for the oceans food web. In 2005 a southward shift in the jet stream, delayed favorable winds and upwelling for the California Current, which normally begins in spring. The winds instead arrived in mid-July, causing high surface water temperatures and very low nutrient production within the nearshore marine ecosystem.

We are not dismissing other potential causes for this years low salmon returns, said Usha Varanasi, NOAA Fisheries Service Science Center Director for the Northwest Region. But the widespread pattern of low returns along the West Coast for two species of salmon indicates an environmental anomaly occurred in the California Current in 2005......... Posted by: Kelly      Read more         Source

March 3, 2008, 8:29 PM CT

Northern Right Whales Head South to Give Birth

Like a number of northerners who head south to warmer climates for the winter, a number of Northern right whales also head south in November and stay into April. Their destination is the only known calving ground for this rare and endangered population-the waters off Florida, Georgia and South Carolina. When they arrive, NOAA researchers are there to greet them, and to take DNA samples.

Eventhough they are large animals, finding them in the ocean is not easy. "Like people, they don't all congregate in one spot," says NOAA researcher Dr. Richard Pace of the challenge. "There may be one here, and three others 50 miles away. And you don't know who will be there this year." Pace, and his colleagues from the Georgia Department of Natural Resources (GDNR) and the Florida Fish and Wildlife Conservation Commission (FWC), are primarily focused on locating right whale newborns and adults who have still not been sampled.

To find the whales, the scientists depend heavily on aerial spotting teams. Once close enough to a whale, the scientists work from an inflatable boat to collect small samples of skin and blubber. The DNA found in the skin can be used to determine sex and create a genetic "fingerprint" for later re-identification. These samples will be added to an already extensive collection of right whale DNA, maintained at Trent University in Ontario, Canada, obtained from approximately 300 individuals......... Posted by: Janet      Read more         Source

March 3, 2008, 8:25 PM CT

Key For Converting Waste To Electricity

Scientists at the University of Minnesota studying bacteria capable of generating electricity have discovered that riboflavin (usually known as vitamin B-2) is responsible for much of the energy produced by these organisms.

The bacteria, Shewanella, are usually found in water and soil and are of interest because they can convert simple organic compounds (such as lactic acid) into electricity, as per Daniel Bond and Jeffrey Gralnick, of the University of Minnesota's BioTechnology Institute and department of microbiology, who led the research effort.

"This is very exciting because it solves a fundamental biological puzzle," Bond said. "Researchers have known for years that Shewanella produce electricity. Now we know how they do it".

The discovery means Shewanella can produce more power simply by increased riboflavin levels. Also, the finding opens up multiple possibilities for innovations in renewable energy and environmental clean-up. The research is reported in the March 3 issue of the Proceedings of the National Academy of Sciences.

The interdisciplinary research team, which included several students, showed that bacteria growing on electrodes naturally produced riboflavin. Because riboflavin was able to carry electrons from the living cells to the electrodes, rates of electricity production increased by 370 percent as riboflavin accumulated......... Posted by: Janet      Read more         Source

March 2, 2008, 9:01 PM CT

Darwin was wrong about the origins of chickens

A novel genetic study has revealed why chickens have yellow legs, demonstrating that though Charles Darwin was right about a number of things, his view on the origins of the chicken was not entirely correct. The study, published February 29 in the open-access journal PLoS Genetics, reveals the genetic basis for the appearance of yellow skin in billions of chickens raised worldwide.

Yellow-skinned chickens have a different version of a gene than their white-skinned cousins. Darwin believed that all chickens came from a wild species known as the red junglefowl. When the scientists looked for the yellow-skin gene in the red junglefowl, they only found the genetic variant that codes for white skin. More surprisingly, when they finally did find the yellow-skin version of the gene, it was present in a completely different wild species: the grey junglefowl.

Greger Larson, a Research Fellow at Uppsala University and at Durham University, UK said: Darwin recognized the importance of studying domestic animals as a model of evolution and this insight has proved enormously influential. The ironic thing is that he believed that dogs were hybrids of several wild ancestors but that chickens only had one, and he was wrong on both counts.

Yellow coloring comes from pigments found in feed called carotenoids. The gene in question codes for an enzyme that degrades carotenoids into a colorless form. White-skinned chickens express this enzyme in skin. In contrast, yellowskinned chickens do not express the enzyme in skin, allowing the carotenoids to accumulate and produce yellow coloring. Interestingly, the gene functions normally in other tissues and yellow-skinned chickens have no general defect in carotenoid metabolism......... Posted by: Kelly      Read more         Source

March 2, 2008, 8:58 PM CT

Zebrafish provide useful screening tool for genes

A small striped fish is helping researchers understand what makes people susceptible to a common form of hearing loss, although, in this case, its not the fishs ears that are of interest. As per a research findings reported in the Feb. 29 issue of the journal PLoS Genetics, scientists at the University of Washington have developed a research method that relies on a zebrafishs lateral linethe faint line running down each side of a fish that enables it to sense its surroundingsto quickly screen for genes and chemical compounds that protect against hearing loss from some medications. The study was funded in part by the National Institute on Deafness and Other Communication Disorders (NIDCD), one of the National Institutes of Health.

The fishs lateral line contains sensory cells that are functionally similar to those found in the inner ear, except these are on the surface of the fishs body, making them more easily accessible, said James F. Battey, Jr., M.D., Ph.D., director of the NIDCD. This means that researchers can very efficiently analyze the sensory structures under different conditions to find out what is likely to cause damage to these structures and, on the other hand, what can protect them from damage.

When people are exposed to some antibiotics and chemotherapy agents, the sensory structures in the inner ear, called hair cells, can be irreversibly damaged, resulting in hearing loss and balance problems. Such medications are called ototoxic. People vary widely in their susceptibility to these agents as well as to damage caused by other chemical agents, loud sounds and aging......... Posted by: Kelly      Read more         Source

March 2, 2008, 8:25 PM CT

Ski tourism stressing capercaillie

Ski tourism is raising stress levels among capercaillie, which could harm the birds fitness and ability to breed successfully, ecologists have found. Writing in the British Ecological Societys Journal of Applied Ecology, scientists warn that forests should be kept free from tourism infrastructure if they are inhabited by capercaillie - a species whose numbers are declining markedly across central Europe.

The study by ecologists from Switzerland, Gera number of and Austria used a new technique to assess the impact of ski tourism on capercaillie. Working in the Southern Black Forest in Gera number of, they collected the birds droppings before and after the start of the ski season, and analysed them for levels of the breakdown products of the stress hormone corticosterone. They observed that levels of the breakdown products of the stress hormone were significantly higher in birds living in areas with moderate or high levels of ski tourism.

One of the study's authors, Dr Lukas Jenni of the Swiss Ornithological Institute says: Ski tourism affects both habitat use and stress hormone levels in capercaillie, and this could adversely affect their body condition and overall fitness. Because of this, we recommend that managers keep forests inhabited by capercaillie free from tourism infrastructure and retain undisturbed forest patches within skiing areas......... Posted by: Kelly      Read more         Source