October 31, 2006, 5:05 AM CT

New Species Discovered Inhawaiian Islands

A three-week scientific expedition to French Frigate Shoals in the Northwestern Hawaiian Islands Marine National Monument returned to Honolulu on Sunday with the discovery of a number of new species and a better understanding of marine biodiversity in the Hawaiian Archipelago.

An all-star team of world-renowned taxonomists (biologists specializing in identifying and naming organisms) and an experienced support crew collected and photographed a number of species that they cannot identify and are believed to be new species to science. The expedition found several potentially new species of crabs, corals, sea cucumbers, sea quirts, worms, sea stars, snails, and clams. A number of other species were observed that are known from other areas but have never been recorded from French Frigate Shoals, the Northwestern Hawaiian Islands, or even the Hawaiian Archipelago. From this expedition, well over a hundred new species records will likely be identified for French Frigate Shoals.

Researchers aboard the National Oceanic and Atmospheric Administration Ship Oscar Elton Sette conducted biodiversity surveys at French Frigate Shoals, with a focus on the small marine organisms - crabs, worms, and a number of other invertebrates, algae, and even microbes - which are often overlooked but that make up the majority of living diversity on coral reefs. "It was a very successful expedition by almost any criterion, and the discovery phase has really only just begun. In the coming months, and even over the next several years, we will be conducting morphological examinations and analyzing genetic sequence data in order to further identify and classify these organisms, and possibly to shed some light on where these species originated," said Dr. Joel W. Martin of the Natural History Museum of Los Angeles County. "What we did not find is also important. There were several groups of animals that we expected to find but did not find, or found only rarely, such as porcellanid crabs. The apparent absence of these common reef organisms may provide insight into how the unique flora and fauna of French Frigate Shoals came to be."........

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October 31, 2006, 4:51 AM CT

Global Warming And Insect Population Growth

Insects have proven to be highly adaptable organisms, able through evolution to cope with a variety of environmental changes, including relatively recent changes in the world's climate. But like something out of a scary Halloween tale, new University of Washington research suggests insects' ability to adapt to warmer temperatures carries an unexpected consequence – more insects.

It appears that insect species that adapt to warmer climates also will increase their maximum rates of population growth, which UW researchers say is likely to have widespread affects on agriculture, public health and conservation.

Many studies have shown that insects readily adapt to the temperature of their environment. For example, those living in deserts easily tolerate high temperatures but are much less tolerant of cold temperatures than insects living in mountains. Now UW biology researchers have found that insect species that have adapted to warmer environments also have faster population growth rates. The research shows, in effect, that "warmer is better" for insects, said Melanie Frazier, a UW biology doctoral student.

"Enhanced population growth rates for butterflies might be a good thing, but enhanced growth rates for mosquito populations is much more dubious," said Frazier, who is lead author of the new research, published in the October edition of the journal The American Naturalist.........

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October 31, 2006, 4:21 AM CT

Insights Into Spiders' Polymer Art

A team of MIT engineers has identified two key physical processes that lend spider silk its unrivaled strength and durability, bringing closer to reality the long-sought goal of spinning artificial spider silk.

Manufactured spider silk could be used for artificial tendons and ligaments, sutures, parachutes and bulletproof vests. But engineers have not managed to do what spiders do effortlessly.

As per a research findings reported in the recent issue of the Journal of Experimental Biology, Gareth H. McKinley, professor of mechanical engineering, and his colleagues examined how spiders spin their native silk fibers, with hopes of ultimately reproducing the process artificially.

McKinley heads the Non-Newtonian Fluid Dynamics research group in MIT's Department of Mechanical Engineering. Non-Newtonian fluids behave in strange and unexpected ways because their viscosity, or consistency, changes with both the rate and the total amount of strain applied to them.

Spider silk is a protein solution that undergoes pronounced changes as part of the spinning process. Egg whites, another non-Newtonian fluid, change from a watery gel to a rubbery solid when heated. Spider silk, it turns out, undergoes similar irreversible physical changes.

Stickiness and Flow........

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October 29, 2006, 7:45 PM CT

Untold Stories Of Elk Skeleton

Seeing the well-preserved antlers, skull and partial skeleton of a very large elk that was found in northern Wisconsin was impressive enough. But what really intrigued Jean Hudson was what was found nearby - a Clovis point, a type of spearhead used by hunters from about 10,000 years ago.

Very few have been found this far north, and this spearhead may be the one that doomed the animal all those millennia ago, says Hudson, an associate professor of anthropology. Or the two specimens could be completely unrelated, she says.

If the two are linked, it would mean that the elk remains are especially rare. More physical evidence of animals such as mastodons, wooly mammoths and giant bison exists than that of elk, says Hudson.

But decoding the secrets of an animal skeleton requires asking the same questions you would at a crime scene investigation: What were the time, cause and circumstances of death? It also involves sometimes getting it wrong, leading to new questions.

A swimmer discovered the antlers of what appears to be a prehistoric elk at the bottom of Middle Eau Claire Lake in Barnes, Wis., last summer. Matt McKay of the Department of Natural Resources in Hayward, who is assigned to the maintenance of the Clam Lake elk herd, estimated the elk would have been between 1,000 and 1,100 pounds when it was alive.........

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October 29, 2006, 6:52 PM CT

Flight of the Bumblebee

Rebecca Flanagan has probably come as close as a human can to reading the mind of a bumblebee.

Flanagan, a graduate student in biological sciences, and Associate Professor Jeffrey Karron are studying the behaviors of bees as they gather pollen - which plant species the bees forage on, which flowers they probe and in what order, and how a number of blooms they visit before moving on to another plant. In doing so, the bees make plant reproduction possible by dispersing pollen.

To predict where each bee that she tracks will carry its pollen next, Flanagan has to literally think like one.

"Once they've learned a foraging style that's been successful, they are more likely to stick with it rather than invest time in learning something new," says Flanagan.

But why go to such lengths to map the flight of the bumblebee? It may seem random and inconsequential. But it is neither, says Karron.

The bees are pivotal players in determining which plant populations survive through successful reproduction. If researchers could better understand nature's decision-making process, then they could use the information to increase crop yields and to boost conservation of native plant communities.

Best bee practices

Because there are a number of bee behaviors, the task isn't simple, but with tedious scrutiny it is documentable.........

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October 27, 2006, 9:23 PM CT

How Female Pronghorns Choose Mate?

When a female animal compares males to choose a mate, she can't order a laboratory genetic screen for each suitor. Instead, she has to rely on external cues that may indicate genetic quality. Until now, biologists have focused on elaborate ornaments, such as the peacock's tail, as cues that females might use.

The thorny problem has been to explain how the connection between male genetic quality and ornament quality can be maintained. If an ornament gives a male a mating advantage, then evolution would rapidly move to the point where all males, regardless of genetic quality, have high-quality ornaments.

"Female mate choice is likely a very important evolutionary force that does much more than select for ornaments in a few species," said John Byers of the University of Idaho. "It may be universally important in maintaining population genetic quality".

In work supported by the National Science Foundation (NSF), Byers has shown that certain females can choose good genes in a species that does not have ornaments, such as the American pronghorn, an antelope-like mammal that evolved in North America. Byers has been studying pronghorn at the National Bison Range, a 30-square-mile National Wildlife Refuge in northwestern Montana, for 20 years, and recognizes all individual pronghorn in the population.........

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October 27, 2006, 9:01 PM CT

Mate-attracting Chemicals

Silkworm moths are white-haired with two-inch wingspans
It's all about "the birds and the bees." And now, "the silkworm moths and the fruit flies".

A chemical ecologist and a genetics researcher at the University of California, Davis, have joined forces to trick fruit flies into thinking that silkworm moths are potential mates.

Groundbreaking research in the labs of chemical ecologist Walter Leal and genetics researcher Deborah Kimbrell shows that genetically engineered fruit flies responded to the silkworm moth scent of a female.

The practical implications of the findings could be widespread. Methods that can attract or repel insects have important applications for agricultural pests and medical entomology. The research could lead to designing better chemicals to attract insects and designing better chemicals to suppress insect communication. That is because insects communicate or smell through their antennae.

A number of insect species, including silkworm moths, release sex pheromones or chemical signals to attract a mate. "Silkworm moths utilize smell more strongly than any other senses," said Leal, professor and chair of the Department of Entomology. "Moths keep on the trail of a scent until they find a female".

"We got a very clear response," he said. "Our electrophysiological recordings and direct stimulation testing showed that the transgenic fruit flies definitely responded to the moth pheromone."........

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October 27, 2006, 5:19 AM CT

What Killed Dinosaurs 65 Million Years Ago

Growing evidence shows that the dinosaurs and their contemporaries were not wiped out by the famed Chicxulub meteor impact alone, as per a paleontologist who says multiple meteor impacts, massive volcanism in India and climate changes culminated in the end of the Cretaceous Period.

The Chicxulub impact may have been the lesser and earlier of a series of meteor impacts and volcanic eruptions that pounded life on Earth for more than 500,000 years, say Princeton University paleontologist Gerta Keller and her collaborators Thierry Adatte from the University of Neuchatel, Switzerland, and Zsolt Berner and Doris Stueben from Karlsruhe University in Gera number of.

A final, much larger and still unidentified impact 65.5 million years ago appears to have been the last straw, said Keller, exterminating two-thirds of all species in one of the largest mass extinction events in the history of life. It's that impact - not Chicxulub - that left the famous extraterrestrial iridium layer found in rocks worldwide that marks the impact that finally ended the Age of Reptiles, Keller believes.

"The Chicxulub impact alone could not have caused the mass extinction," said Keller, "because this impact predates the mass extinction".

Keller is scheduled to present that evidence at the annual meeting of the Geological Society of America (GSA) in Philadelphia, on Tuesday, October 24, 2006.........

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October 27, 2006, 4:39 AM CT

What Makes A Bee A He Or A She?

Three years ago, researchers pinpointed a gene called csd that determines gender in honey bees, and now a research team led by University of Michigan evolutionary biologist Jianzhi "George" Zhang has unraveled details of how the gene evolved. The new insights could prove useful in designing strategies for breeding honey bees, which are major pollinators of economically important crops-and notoriously tricky to breed.

The findings of Zhang and collaborators appear in a special issue of Genome Research devoted to the biology of the honey bee. The issue will be published online and in print Oct. 26, coinciding with the publication of the honey bee genome sequence in the journal Nature.

Researchers have long known that in bees-as well as wasps, ants, ticks, mites and some 20 percent of all animals-unfertilized eggs develop into males, while females typically result from fertilized eggs. But that's not the whole story, and the discovery in 2003 of csd (the complementary sex determination gene) helped fill in the blanks. The gene has a number of versions, or alleles. Males inherit a single copy of the gene; bees that inherit two copies, each a different version, become female. Bees that have the misfortune of inheriting two identical copies of csd develop into sterile males but are quickly eaten at the larval stage by female worker bees.........

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October 26, 2006, 4:50 AM CT

Nuclear Receptors In Bee Genome

Susan Fahrbach, a Wake Forest University biologist, is among the more than 170 scientists who helped decode the honey bee genome. She contributed to the article on the bee genome sequence that appears in the Oct. 26 issue of Nature.

Her piece of the puzzle -- analyzing the nuclear hormone receptors found in the bee genome -- also appears in the current issue of Insect Molecular Biology.

The honey bee was chosen to have its genome sequenced because of its dual importance to agriculture and medicine. The well-known pollination activities of honey bees add billions of dollars of value to U.S. crops every year, but bees are also used in the laboratory to study issues correlation to human health such as immunity, longevity and diseases of the X chromosome. In addition, brain researchers are interested in the honey bee's complex social life and their ability to communicate the location of flowers to other members of the hive.

Fahrbach, Reynolds Professor of Developmental Neuroscience, and her co-scientists at Wake Forest and the University of Illinois, searched the genome sequence to find all of the nuclear receptors encoded in the bee genome. They observed that the same nuclear receptors that control the development of the nervous system during the early.........

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