Sun, 11 Mar 2007 18:20:25 GMT

Large-billed Reed-warbler Bird Rediscovered in Thailand After 130 Years

After 130 years of its hide-n-seek with scientists, the wetland bird — large-billed reed-warbler has been spotted once again at a wastewater treatment plant in Thailand, the Birdlife International informed.

It has been discovered in 1867 in the Sutlej Valley of India, and since then it had not been seen. Thus, little is known about the bird. I6ts being so rare had kicked up debates among scientists on
if it represented a true species or was an aberrant individual of a more common species.

It was on on March 27, 2006, the debate apparently got settled with one of the bird species having being captured by Philip Round, an ornithologist at Bangkok’s Mahidol University. The bird has been captured at a wastewater treatment center outside Bangkok, according to the conservation organization in Cambridge, England.

Philip Round said in a statement,

Although reed-warblers are generally drab and look very similar, one of the birds I caught that morning struck me as very odd, something about it didn’t quite add up.

Then, it dawned on me. I was probably holding a large-billed reed-warbler,” he said. “I was dumbstruck.

The birds photographs and DNA samples sent to the Staffan Bensch of Sweden’s Lund University confirmed Rounds findings. Bensch, who had previously examined this Indian specimen, confirmed that the bird represented a valid species.

Photo Courtesy: AP/Phillip Round/The Wetland Trust, HO

Posted by: Irani      Read more     Source

March 5, 2007, 10:05 PM CT

How buddies help alpha males get the girl

Why do some individuals sacrifice their own self-interest to help others? The evolution and maintenance of cooperative behavior is a classic puzzle in evolutionary biology. In some animal societies, cooperation occurs in close-knit family groups and kin selection explains apparently selfless behavior. Not so for the lance-tailed manakin. Males of this little tropical bird cooperate in spectacular courtship displays with unrelated partners, and the benefits of lending a helping wing may only come years down the line. Instead of fighting over females, pairs of male lance-tailed manakins team up to court prospective mates. Two males dance together for interested females, using tightly synchronized 'leapfrog' and flight displays to impress the opposite sex. But when the dance is over, only the dominant male, the alpha, gets the chance to mate. Emily DuVal, of UC Berkeley's Museum of Vertebrate Zoology, studied these birds to answer the question of why subordinate beta males cooperate. Starting in 1999, DuVal color-banded and observed wild lance-tailed manakins in Panam to follow changes in status over multiple years. Then she used genetic analyses to determine chicks' paternity and genetic relationships among adults.

The results of DuVal's work, would be reported in the recent issue of The American Naturalist, showed that male partners were unrelated, and betas rarely sired chicks, ruling out two of the major hypotheses explaining males' cooperative behavior. Following males across years showed that betas became alphas more often than other males, but not necessarily at the same territory where they were betas. Even when the local alpha slot was empty, some betas moved to be helpers elsewhere rather than take over the vacant position. "Without being an alpha, there's essentially no chance for these males to reproduce," says DuVal. "My results suggest that betas could actually benefit from staying betas for a while, for example by gaining courtship skills during a sort of apprenticeship or by forming alliances with other males who later act as their betas." These results contrast with those from studies of other birds with cooperative courtship displays: wild turkeys strut cooperatively with close relatives, and ruffs (a shorebird) form alliances of males that often both mate while they are partners. These contrasts are interesting because they show that similar behavior can result from very different social and selective environments. DuVal is now a postdoctoral researcher at the Max Planck Institute for Ornithology, Gera number of, where she is investigating how female lance-tailed manakins choose their mates......... Posted by: Kelly      Read more         Source

March 5, 2007, 9:54 PM CT

Migration Of Avian Flu Virus

UC Irvine scientists have combined genetic and geographic data of the H5N1 avian flu virus to reconstruct its history over the past decade. They observed that multiple strains of the virus originated in the Chinese province of Guangdong, and they identified a number of of the migration routes through which the strains spread regionally and internationally.

By knowing where H5N1 strains develop and migrate, health officials can better limit the spread of the virus by strategically intervening. Local vaccinations can be better administered by using strains from regions that have repeatedly contributed to infections.

"If you can control the virus at its source, you can control it more efficiently," said Walter Fitch, professor of ecology and evolutionary biology in the School of Biological Sciences at UCI and co-author of the study. "With a road map of where the strain has migrated, you're more likely to isolate the strain that you should be using to make the vaccine".

The study appears this week in the online early edition of the Proceedings of the National Academy of Sciences.

This research offers the first statistical analysis detailing the geographic distribution of influenza A H5N1, the bird flu strain. While prior work informally identified H5N1 strains by location, the UCI analysis is the first to systematically track the migration of H5N1 through its evolutionary history, adding new details that identify the relative importance of the geographic and evolutionary advances the virus makes......... Posted by: Kelly      Read more         Source

March 1, 2007, 10:00 PM CT

Evolutionary History Of Vespid Wasps

Researchers at the University of Illinois have conducted a genetic analysis of vespid wasps that revises the vespid family tree and challenges long-held views about how the wasps' social behaviors evolved. In the study, reported in the Feb. 21 Proceedings of the National Academy of Sciences, the scientists found genetic evidence that eusociality (the reproductive specialization seen in some insects and other animals) evolved independently in two groups of vespid wasps.

These findings contradict an earlier model of vespid wasp evolution, which placed the groups together in a single lineage with a common ancestor.

Eusocial behavior is quite rare, and generally involves the breeding of different reproductive classes within a colony. The sterile members of the group perform tasks that support their fertile counterparts. Eusociality occurs in only a few species of insects, rodents, crustaceans and other arthropods.

The evolution of eusociality in wasps has long been a source of debate, said U. of I. entomology graduate student Heather Hines and entomology professor Sydney Cameron, who is the principal investigator of the study. A previous model of vespid wasp evolution placed three subfamilies of wasps - the Polistinae, Vespinae and Stenogastrinae - together in a single evolutionary group with a common ancestor. This model did not rely on a genetic analysis of the wasps, but instead classified them as per several physical and behavioral traits......... Posted by: Kelly      Read more         Source

March 1, 2007, 9:48 PM CT

A frenzy of fruit fly methods

For the past century, fruit fliesor Drosophilahave provided innumerable insights into the genetics and biology of development, learning and memory, behavior, vision, and other processes. But for scientists who conduct these studies, the logistics of housing and feeding the hundreds or thousands of flies needed for experiments can be daunting. To address this concern, the current issue of Cold Spring Harbor Protocolsreleased online today www.cshprotocols.org includes a series of articles for maintaining and manipulating flies in the laboratory.

One of the articles, freely accessible at http://www.cshprotocols.org/cgi/content/full/2007/6/pdb.ip35, provides tried-and-true advice on how to maintain fly stocks, set up appropriate matings, and control contamination and diseases. Because flies are considered a premier model organism for genetics studies, the featured article also presents techniques for inducing mutations into the DNA of flies. The article will be useful for biologists starting to work with flies in the laboratory, as well as for existing fly laboratories looking to reorganize.

Other articles published recently include methods for harvesting and analyzing fly embryos, as well as protocols for characterizing proteins from a variety of sources. These publications join in a growing library of high-quality methods from Cold Spring Harbor Protocols For a complete list of freely accessible protocols......... Posted by: Kelly      Read more         Source

March 1, 2007, 9:45 PM CT

Why do birds migrate?

Why do some birds fly thousands of miles back and forth between breeding and non-breeding areas every year whereas others never travel at all? .

One textbook explanation suggests either eating fruit or living in non-forested environments were the precursors needed to evolve migratory behavior.

Not so, report a pair of ecologists from The University of Arizona in Tucson. The pressure to migrate comes from seasonal food scarcity.

"It's not just whether you eat insects, fruit, nectar or candy bars or where you eat them -- it matters how reliable that food source is from day-to-day," said W. Alice Boyle. "For example, some really long-distance migrants like arctic terns are not fruit-eaters".

Boyle, an adjunct lecturer in UA's department of ecology and evolutionary biology and co-author Courtney J. Conway, a UA assistant professor of natural resources and a research scientist with the U.S. Geological Survey, report their findings in the March 2007 issue of American Naturalist.

To figure out the underlying pressures that drive some birds to leave home for the season, the team wanted to examine a related set of species and compare their size, food type, habitat, migratory behavior and whether they fed in flocks.

Boyle and Conway focused on 379 species of New World flycatchers from the suborder Tyranni. One of the largest groups of New World birds, the Tyranni includes kingbirds, flycatchers, phoebes and such southern Arizona birdwatchers' delights as vermillion flycatchers and rose-throated becards. Tropical members include manakins and cotingas......... Posted by: Kelly      Read more         Source

February 28, 2007, 9:43 PM CT

Iron and phytoplankton, fish populations

A new study suggests that the iron-rich winter runoff from Pacific Northwest streams and rivers, combined with the wide continental shelf, form a potent mechanism for fertilizing the nearshore Pacific Ocean, leading to robust phytoplankton production and fisheries.

The study, by three Oregon State University oceanographers, was just published by the American Geophysical Union in its journal, Geophysical Research Letters.

West coast researchers have found that ocean chlorophyll levels, phytoplankton production and fish populations generally increase in the Pacific Ocean the farther north you go (from southern California to northern Washington). No one has a definitive explanation for the increase, the OSU researchers say, though some scientists have suspected river runoff may play a role. That theory has generally been discounted, they added, because river flows are low in the summer when phytoplankton blooms occur.

In their study, however, the OSU researchers observed that Northwest rivers churn out huge amounts of iron in the winter and deposit it on the continental shelf, where it sits until the spring and summer winds begin the ocean upwelling process. The authors studied the relationships between phytoplankton, river runoff and shelf width all along the West Coast......... Posted by: Kelly      Read more         Source

February 27, 2007, 9:37 PM CT

Light On Blue Whales And Their Calls

Using a variety of new approaches, researchers at Scripps Institution of Oceanography at UC San Diego are forging a new understanding of the largest mammals on Earth.

In one recently published study on blue whales, Scripps scientists used a combination of techniques to show for the first time that blue whale calls can be tied to specific behavior and gender classifications. In a separate study, scientists used recordings of blue whale songs to determine the animal's population distributions worldwide.

While the specific function of songs and calls produced by whales remains a mystery to a large degree, the sounds are thought to mediate social interactions between the animals.

The first study, led by Scripps postdoctoral researcher Erin Oleson and Scripps scientist John Hildebrand, describes the behavioral context of calls produced by eastern North Pacific blue whales. Few scientists have attempted to link sound production with specific behaviors or environmental conditions to attempt to determine the significance of whale calls.

"This is the first study that has been able to study the calls by directly observing the animal while it is calling and gathering key information such as depth and body orientation-getting a sense of what the animal is doing underwater," said Oleson. "Once you understand the context of specific types of sounds, then you can use those sounds to infer something about what they are doing when you are not there to actually see them doing it."........ Posted by: Kelly      Read more         Source

February 27, 2007, 9:22 PM CT

Brain maps online

Digital atlases of the brains of humans, monkeys, dogs, cats, mice, birds and other animals have been created and posted online by scientists at the UC Davis Center for Neuroscience.

BrainMaps.org features the highest resolution whole-brain atlases ever constructed, with over 50 terabytes of brain image data directly accessible online. Users can explore the brains of humans and a variety of other species at an unprecedented level of detail, from a broad view of the brain to the fine details of nerves and connections. The website also includes a suite of free, downloadable tools for navigating and analyzing brain data.

"A number of users have described it as a 'Google Maps' of the brain," said Shawn Mikula, a postdoctoral researcher at UC Davis who is first author on a paper describing the work.

The high-resolution maps will enable scientists to use "virtual microscopy" to compare healthy brains with others, looking at structure, gene expression and the distribution of different proteins. They will enable better understanding of the organization of normal brains, and could help scientists in identifying fine morphological and chemical abnormalities underlying Alzheimer's, Parkinson's and other neurological diseases, Mikula said.

To make the maps, the scientists started with sections of brain mounted on microscope slides. Those slides were scanned to create image files or "virtual slides," and assembled like tiles into composite images. The maps have a resolution of better than half a micrometer per pixel, or 55,000 dots per inch, with virtual slides approaching 30 gigabytes in size each......... Posted by: Kelly      Read more         Source

February 27, 2007, 7:56 PM CT

Why migrate? It's not for the fruit

Why do some birds fly thousands of miles back and forth between breeding and non-breeding areas every year whereas others never travel at all? One textbook explanation suggests that eating fruit or living in nonforested environments were the precursors needed to evolve migratory behavior. Not so, report ecologists W. Alice Boyle and Courtney J. Conway of the University of Arizona, Tucson, in the recent issue of the American Naturalist. Conway is also a research scientist with the U.S. Geological Survey. The two showed the pressure to migrate comes from seasonal food scarcity. It's the first time the technique called phylogenetic independent contrasts has been used to identify the causes of bird migration. "It's not just whether you eat insects, fruit, or candy bars, or where you eat them it matters how reliable that food source is from day-to-day," Boyle said. "For example, some really long-distance migrants like Arctic Terns are not fruit-eaters."

The new research indicates that one strategy for dealing with seasonal changes in food availability is migration. The team also observed that birds that forage with others of the same species are less likely to migrate. "Flocking can be an alternative way of dealing with food shortages," Boyle said. When birds band together to search for food, the group is more likely to find a new patch of food than is one lone individual. To figure out the underlying pressures that drive some birds to leave home for the season, Boyle and Conway focused on 379 species of New World flycatchers from the suborder Tyranni. For all those species the researchers compared the species' size, food type, habitat, migratory behavior, and whether the birds fed in flocks. A universal assumption about bird migration has been that short-distance migration is an evolutionary stepping stone to long-distance migration. The team's work contradicts that idea by showing that short-distance migrants are inherently different from their globe-trotting cousins......... Posted by: Kelly      Read more         Source