May 7, 2008, 6:26 PM CT

Platypus Genome Decoded

The curious discovery of the duck-billed, egg-laying, otter-footed, beaver-tailed, venomous platypus in Australia in 1798 convinced British researchers that it must be a hoax. Sketches of its appearance were believed to be impossible.

But new research proves that the oddness of the platypus' looks isn't just skin-deep. Platypus DNA is an equally cobbled-together array of avian, reptilian and mammalian lineages that may hold clues for human disease prevention.

Mark Batzer and Andrew C. Pereboom of Louisiana State University, along with an international group of researchers led by Wes Warren at Washington University in St. Louis, Missouri, recently completed the first draft sequence and analysis of the platypus genome.

It was the first genome sequencing project of a mammal that lays eggs, confirming that platypus DNA also looks like something of a patchwork.

"Their genomic organization was strange and a little unexpected," says Batzer. "It appeared much more bird- and reptile-like than mammalian, even though it is indeed classified as a mammal.".

Having the genome in hand is a huge step for researchers seeking new details about evolution and human disease. The fact that the platypus is an ancient animal that is relatively primitive and unchanged may be a scientific boon for researchers......... Posted by: Kelly      Read more         Source

May 5, 2008, 5:46 PM CT

Global warming will negatively impact tropical species

Global warming is likely to reduce the health of tropical species, researchers from UCLA and the University of Washington report May 6 in Proceedings of the National Academy of Sciences.

At the same time, a little bit of warming may actually move certain organisms, especially insects, in the high latitudes closer to their optimal temperature, the scientists say.

"In the tropics, most of the organisms we have studied, from insects to amphibians and reptiles, are already living at their optimal physiological temperatures," said Curtis Deutsch, UCLA assistant professor of atmospheric and oceanic sciences and co-author of the study. "When warming starts, they do less well as they move toward the hottest end of their comfort range. Even a modest increase in temperature appears rather large to them and negatively impacts their population growth rates." .

Why should we be concerned with the fate of insects in the tropics? .

"The biodiversity of the planet is concentrated in tropical climates, where there is a tremendous variety of species," Deutsch said. "This makes our finding that the impacts of global warming are going to be most detrimental to species in tropical climates all the more disturbing. In addition, what hurts the insects hurts the ecosystem. Insects carry out essential functions for humans and ecosystems such as pollinating our crops and breaking down organic matter back into its nutrients so other organisms can use them. Insects are essential to the ecosystem." ......... Posted by: Kelly      Read more         Source

May 2, 2008, 8:14 AM CT

Bees Disease - One Step Closer To Finding A Cure

Researchers in Gera number of have discovered a new mechanism of infection for the most fatal bee disease. American Foulbrood (AFB) is the only infectious disease which can kill entire colonies of bees. Every year, this notifiable disease is causing considerable economic loss to beekeepers all over the world. The only control measure is to destroy the infected hive.

The mechanism of infection (pathogenic mechanism) was originally believed to be through the growth of a bacterium called Paenibacillus larvae in the organ cavity of honey bee larvae. The accepted view was that the bacteria germinate preferentially at either end of the gut of honey bee larvae then make holes in the gut wall and enter the larval organ cavity, the presumed primary place of bacterial proliferation.

In a paper published in Environmental Microbiology, Professor Elke Genersch and his colleagues in Berlin explain that they have discovered that these bacteria cause infection in a completely different way. They colonize the larval midgut, do most of their multiplying in the mid-gut - living from the food ingested by the larvae - until eventually the honey bee larvae gut contains nothing but these disease-causing (pathogenic) bacteria. It isn't until then that the bacteria 'burst' out of the gut into the organ cavity thereby killing the larvae. These findings are a major breakthrough in honeybee pathology......... Posted by: Kelly      Read more         Source

April 30, 2008, 6:58 PM CT

It's a unisex brain with specific signals

Research by Yale researchers shows that males and females have essentially unisex brains at least in flies as per a recent report in Cell designed to identify factors that are responsible for sex differences in behavior.

The scientists showed that a courting song and dance routine that only male flies naturally perform one wing is lifted and wiggled to make a humming song can also be triggered in female flies by artificially stimulating particular brain cells that are present in both sexes. It isnt what youve got its how you use it, the authors say.

It appears there is a largely bisexual or unisex brain. Anatomically, the differences are subtle and a few critical switches make the difference between male and female behavior, said senior author Gero Miesenboeck, formerly of Yale University and now at the University of Oxford.

As per the authors, most male animals have to perform elaborate courtship displays to try to convince the female that they are worthy mates. Their study was designed to see what neurons were responsible for behavior in the courtship dance of flies, and how the neural circuits in males and females differed. To do this, they genetically engineered specific neurons in the fly to respond to light. This optical trick allowed them to activate the neural circuits that control the behavior pattern directly......... Posted by: Kelly      Read more         Source

April 30, 2008, 6:36 PM CT

Sequencing of Protein from T. rex Confirms Dinosaurs' Link to Birds

Researchers have put more meat on the theory that dinosaurs' closest living relatives are modern-day birds.

Molecular analysis, or genetic sequencing, of a 68-million-year-old Tyrannosaurus rex protein from the dinosaur's femur confirms that T. rex shares a common ancestry with chickens, ostriches, and to a lesser extent, alligators.

The dinosaur protein was wrested from a fossil T. rex femur discovered in 2003 by paleontologist John Horner of the Museum of the Rockies; the bone was found in a fossil-rich stretch of land in Wyoming and Montana.

The new research results, published this week in the journal Science, represent the first use of molecular data to place a non-avian dinosaur in a phylogenetic tree, a "tree of life," that traces the evolution of species.

"These results match predictions made from skeletal anatomy, providing the first molecular evidence for the evolutionary relationships of a non-avian dinosaur," says Science paper co-author Chris Organ, a researcher at Harvard University. "Even though we only had six peptides--just 89 amino acids--from T. rex, we were able to establish these relationships.".

"Tests of the peptide sequences in T. rex bone fossils have confirmed that newer methods of molecular systematics agree with more traditional methods of taxonomic classification based on morphology, or shapes," says Paul Filmer, program director in the National Science Foundation (NSF)'s Division of Earth Sciences, which funded the research......... Posted by: Kelly      Read more         Source

April 30, 2008, 5:52 PM CT

Photochemical Compass for Bird Navigation

A team of scientists at Arizona State University and the University of Oxford are the first to model a photochemical compass that may simulate how migrating birds use light and Earth's weak magnetic field to navigate. The team reports in the April 30, 2008, online issue of Nature that the photochemical model becomes sensitive to the magnitude and direction of weak magnetic fields similar to Earth's when exposed to light. The research funded by the National Science Foundation (NSF) demonstrates that this phenomenon, known as chemical magnetoreception, is feasible and gives insight into the structural and dynamic design features of a photochemical compass.

The most common bird migration pattern in the northern hemisphere is to fly north in the summer to breed in the Artic and to fly south to warmer regions for the winter.

Regardless of which way they are flying, migrating birds are important ecologically as a food source for other animals. They also transport plankton, materials involved in plant reproduction and hitchhikers such as ticks and lice, which can carry micro-organisms harmful to human health.

About 50 animal species, ranging from birds and mammals to reptiles and insects, use Earth's weak magnetic field for navigation. Earth's magnetic field ranges from approximately 30 to 60 millionths of one tesla. By comparison, magnetic resonance imaging, or MRI, uses magnetic fields from 1.5 to 3.0 tesla......... Posted by: Kelly      Read more         Source

April 30, 2008, 5:38 PM CT

Engineering and invention on the half-shell

Marine snails, sea urchins, and other animals from the sea are teaching scientists in UC Riversides Department of Chemical and Environmental Engineering how to make the world a better place.

Consider, for example, the possibilities of designing a lightweight armor that would protect U.S. soldiers in Iraq from Improvised Explosive Devices. Or, what flexible ceramics might offer industry. Or, how everyone could benefit from new ways of producing and storing energy.

Nature holds these secrets and the answers to the questions that Prof. David Kisailuss research group is learning how to ask. My hope, Kisailus said, is that we can truly learn from these organisms how to design, optimize, and synthesize engineering materials that display properties that we as engineers can only dream of.

Studying ocean animals daily as they grow seems a tough task for Inland Southern California scientists. Instead of commuting to the coast, the scientists have brought the oceans to UCR in a unique 500-gallon seawater system that dominates the Biomimetic and Nanostructured Materials Laboratory, offering homes for both coldwater (60 degrees Fahrenheit) and tropical (80 degrees Fahrenheit) species.

While some people trek to exotic, faraway locales to admire the beauty of coral reefs, at UCR, people simply can visit Bourns Hall to see a dramatic and authentic tropical coral reef ecosystem. Another showcase tank boasts a thriving coldwater marine population that includes Californias red abalone (Haliotis rufescens), purple and brown sea urchins (Strongylocentrotus purpuratus and Lytechinus pictus), giant keyhole limpets (Megathura crenulata), several coral species (Balanophyllia elegans, Astrangia lajollaensis and Paracyathus stearnsi), along with numerous colonies of club-tipped corallimorpharians (Corynactis californica)......... Posted by: Kelly      Read more         Source

April 29, 2008, 8:33 PM CT

Bison can thrive again

Bison can repopulate large areas from Alaska to Mexico over the next 100 years provided a series of conservation and restoration measures are taken, according to continental assessment of this iconic species by the Wildlife Conservation Society and other groups. The assessment was authored by a diverse group of conservationists, scientists, ranchers, and Native Americans/First Nations peoples, and appears in the recent issue of the journal Conservation Biology.

The authors say that ecological restoration of bison, a keystone species in American natural history, could occur where conservationists and others see potential for large, unfettered landscapes over the next century. The general sites identified in the paper range from grasslands and prairies in the southwestern U.S., to Arctic lowland taiga in Alaska where the sub-species wood bison could once again roam. Large swaths of mountain forests and grasslands are identified as prime locations across Canada and the U.S., while parts of the desert in Mexico could also again support herds that once lived there.

The researchers assessed the restoration potential of these areas by creating a conservation scorecard that evaluated the availability of existing habitat, potential for interaction with other native species, such as elk, carnivores, prairie dogs, and grassland birds, and a variety of other factors, including the socio-economic climate of the regions and the potential for cultural re-connection with bison. The higher the score of these factors, the more likely restoration could take place over time......... Posted by: Kelly      Read more         Source

April 28, 2008, 5:48 PM CT

Protect Endangered Right Whales

Endangered North Atlantic right whales are safer along Massachusetts Bay's busy shipping lanes this spring, thanks to a new system of smart buoys. The buoys recognize whales' distinctive calls and route the information to a public Web site and a marine warning system, giving ships the chance to avoid deadly collisions.

The 10-buoy Right Whale Listening Network (http://listenforwhales.org/) -- developed at the Cornell Lab of Ornithology and Woods Hole Oceanographic Institution -- is arriving barely in time for the beleaguered right whale. The species was hunted to the brink of extinction centuries ago, and now fewer than 400 of the 50-ton black giants remain. Collisions with ships are currently a leading cause of death.

Living 60 years or more, right whales skim tiny plankton from the shallow coastal waters of the Atlantic. Each winter and spring, a number of right whales congregate -- along with fin, minke and humpback whales -- in the Stellwagen Bank National Marine Sanctuary, 25 miles east of Boston Harbor, which bisects official shipping lanes used by some 1,500 container ships, tankers, cruise liners and fishing boats every year.

"For the first time, we can go online and hear up-to-the-minute voices of calling whales, and see where those whales are in the ocean off Boston and Cape Cod," said Christopher Clark, director of the Bioacoustics Research Program at the Lab of Ornithology. "Better yet, those calls immediately get put to use in the form of timely warnings to ship captains"......... Posted by: Kelly      Read more         Source

April 24, 2008, 10:30 PM CT

Are Ice Age relics the next casualty of climate change?

The Wildlife Conservation Society (WCS) recently launched a four-year study to determine if climate change is affecting populations of a quintessential Arctic denizen: the rare musk ox. Along with collaborators from the National Park Service, U. S. Geological Survey, and Alaska Fish and Game, Wildlife Conservation Society scientists have already equipped six musk ox with GPS collars to better understand how climate change may affect these relics of the Pleistocene.

The research team will be assessing how musk ox are faring in areas along the Chukchi and northern Bering Seas, and the extent to which snow and icing events, disease, and possibly predation may be driving populations.

Musk ox are a throwback to our Pleistocene heritage and once shared the landscape with mammoths, wild horses, and sabered cats, said the studys leader Dr. Joel Berger, a Wildlife Conservation Society scientist and professor at the University of Montana. They may also help researchers understand how arctic species can or cannot adapt to climate change.

Once found in Europe and Northern Asia, today musk ox are restricted to Arctic regions in North America and Greenland eventhough they have been introduced into Russia and northern Europe. They have been reintroduced in Alaska after being wiped out in the late 19th century. Currently they found in two national parks: Alaskas Bering Land Bridge National Park and Cape Krusenstem National Monument......... Posted by: Kelly      Read more         Source

April 24, 2008, 10:13 PM CT

Ways To Fight Lake Trout Invasion

Natural barriers like waterfalls play an important role in preventing lake trout from spreading through Glacier National Park, so maintaining those barriers should be a priority, Montana State University scientists said after conducting a four-year study in the park.

Park workers might have to remove ice, logs or debris to keep the water from rising behind those barriers, said graduate student Michael Meeuwig and his adviser Christopher Guy. If they don't, lake trout will have an easier time swimming up the rivers and invading new lakes.

Monitoring and maintaining natural barriers are easier than trying to get rid of lake trout after they've entered a lake, Guy said. He pointed to the expense and effort spent at Yellowstone National Park where lake trout prey on native cutthroat trout in Yellowstone Lake. In Glacier National Park, lake trout compete with native bull trout.

Guy, assistant unit leader for the Montana Cooperative Fishery Research Unit at MSU, heads the Glacier research project with Wade Fredenberg of the Creston Fish and Wildlife Center near Kalispell. The U.S. Geological Survey funds the research.

Non-native lake trout were introduced into Flathead Lake about 100 years ago and are thought to bethe source of the lake trout that are threatening Glacier's native bull trout population. Meeuwig's and Fredenberg's work have observed that lake trout have since invaded eight lakes on the west side of the park: Bowman Lake, Harrison Lake, Kintla Lake, Lake McDonald, Logging Lake, Lower Quartz Lake, Quartz Lake and Rogers Lake......... Posted by: Kelly      Read more         Source

April 24, 2008, 10:07 PM CT

Mosquitoes Fatten Up, Slow Down For Winter

Two genes that help insulin regulate mosquitoes' growth have been identified as key contributors to how the insects enter a dormant state to survive winter's cold.

The research finding broadens the understanding of the mosquito life cycle and appears to shed some light on how other insects and invertebrate species weather the winter months.

The shorter days of autumn trigger certain species of mosquitoes into diapause, a hibernation-like state of arrested development that allows them to survive through the winter. But this new research has determined that a hormonal response is behind the mosquito's ability to store up extra fat and halt reproductive activity in preparation for its months-long dormancy, said David Denlinger, senior author of the study and professor of entomology at Ohio State University.

The research appears online this week in the Proceedings of the National Academy of Sciences.

Denlinger's lab is working with Culex pipiens, a common mosquito in the United States and the species that carries the West Nile virus in North America. He and his colleagues have identified several genes in this mosquito that function within the insulin signaling pathway, the mechanism necessary for diapause to begin. However, they focused on two genes that appear to have the most power in regulating the insect's transition into a dormant state......... Posted by: Kelly      Read more         Source

April 22, 2008, 9:36 PM CT

Ugandan monkeys harbor unknown poxvirus

Scientists report this month that red colobus monkeys in a park in western Uganda have been exposed to an unknown orthopoxvirus, a pathogen correlation to the viruses that cause smallpox, monkeypox and cowpox. Most of the monkeys screened harbor antibodies to a virus that is similar - but not identical - to known orthopoxviruses.

The findings appear online in the journal Emerging Infectious Diseases.

This is the first effort to screen Ugandan red colobus monkeys for orthopoxviruses, said Tony Goldberg, a professor of veterinary pathobiology and of anthropology at the University of Illinois and lead author on the study.

"Considering that we found evidence for a new poxvirus pretty much in the first place that we chose to look is suggestive that the actual diversity of poxviruses in nature, particularly in relatively unstudied areas like sub-Saharan Africa, may be much greater than we originally thought," Goldberg said.

The study was begun in 2006 when Colin Chapman, a researcher at McGill University, invited Goldberg to collaborate on a health assessment of two groups of red colobus monkeys in Kibale National Park, in western Uganda.

Chapman, also an associate scientist with the Wildlife Conservation Society, had spent two decades studying the behavior and ecology of the monkeys. He wanted to broaden the study to include an analysis of the pathogens they carried. Wildlife veterinarians from the Wildlife Conservation Society helped collect the samples, and a team from Oregon Health and Science University, led by Mark Slifka, conducted immunological analyses to characterize the virus......... Posted by: Kelly      Read more         Source

April 22, 2008, 9:31 PM CT

Can Certain Metals Repel Sharks from Fishing Gear?

Sharks in captivity avoid metals that react with seawater to produce an electric field, a behavior that may help fishery biologists develop a strategy to reduce the bycatch of sharks in longline gear. Shark bycatch is an increasing priority worldwide given diminished populations of a number of shark species, and because sharks compete with target species for baited lines, reducing fishing efficiency and increasing operating costs.

A recent study by NOAA researchers and his colleagues on captive juvenile sandbar sharks showed the presence of an electropositive alloy, in this case palladium neodymium, clearly altered the swimming patterns of individual animals and temporarily deterred feeding in groups of sharks. Rare earth metals have previously been reported to deter spiny dogfish from attacking bait due to interactions with the shark's electroreceptive system, which detects weak electric fields including those generated by their prey. Electric fields generated by electropositive alloys are believed to deter or repel sharks by overloading their sensory systems.

"Individual sandbar sharks would generally not approach the metal ingots closer than about 24 inches, nor attack pieces of cut bait suspended within approximately 12 inches," said Richard Brill, a research scientist at NOAA's Northeast Fisheries Science Center and head of the Cooperative Marine Education and Research (CMER) Program at the Virginia Institute of Marine Science. "This study clearly shows the alloy has the potential to repel sharks from pelagic longline fishing gear so they are not caught as bycatch, but the optimal size and shape of the alloy and other factors needs to be determined. This is a promising step"......... Posted by: Kelly      Read more         Source

April 21, 2008, 7:43 PM CT

Lizard hunting styles impact ability to walk, run

The technique lizards use to grab their grub influences how they move, as per scientists at Ohio University.

A research team led by doctoral student Eric McElroy tracked 18 different species of lizards as they walked or ran in order to understand how their foraging styles impact their biomechanics. The study, funded by the National Science Foundation, was featured in the April 1 edition of the Journal of Experimental Biology.

Lizards use two basic foraging techniques. In the first approach, aptly dubbed sit-and-wait, lizards spend most of their time perched in one location waiting for their prey to pass. Then, with a quick burst of speed, they run after their prey, snatching it up with their tongues.

In the other form of foraging, known as wide or active foraging, lizards move constantly but very slowly in their environment, using their chemosensory system to stalk their prey, as per the research team, which included McElroy's adviser Stephen Reilly, professor of biological sciences, and undergraduate honors thesis student Kristin Hickey.

Eventhough wide foraging evolved from the sit-and-wait technique, these two styles are almost opposites. Some wide foragers are on the move about 80 percent of the time while sit-and-wait foragers may move only about 10 percent of the time, said Reilly, co-author of a recent book on the topic, Lizard Ecology, published by the Cambridge University Press......... Posted by: Kelly      Read more         Source

April 13, 2008, 8:45 PM CT

Insects evolved radically different strategy to smell

Darwin's tree of life represents the path and estimates the time evolution took to get to the current diversity of life. Now, new findings suggest that this tree, an icon of evolution, may need to be redrawn. In research would be reported in the April 13 advance online issue of Nature, scientists at Rockefeller University and the University of Tokyo have joined forces to reveal that insects have adopted a strategy to detect odors that is radically different from those of other organisms -- an unexpected and controversial finding that may dissolve a dominant ideology in the field.

Since 1991, scientists assumed that all vertebrates and invertebrates smell odors by using a complicated biological apparatus much like a Rube Goldberg device. For instance, someone pushing a doorbell would set off a series of elaborate, somewhat wacky, steps that culminate in the rather simple task of opening the door.

In the case of an insect's ability to smell, scientists believed that when molecules wafting in the air travel up the insect's nose, they latch onto a large protein (called a G-protein coupled odorant receptor) on the surface of the cell and set off a chain of similarly elaborate steps to open a molecular gate nearby, signaling the brain that an odor is present.

"It's that way in the nematode, it's that way in mammals, it's that way in every known vertebrate," says co-author of study Leslie Vosshall, head of the Laboratory of Neurogenetics and Behavior at Rockefeller University. "So it's actually unreasonable to believe that insects use a different strategy to detect odors. But here, we show that insects have gotten rid of all this stuff in the middle and activate the 'gate' directly"......... Posted by: Kelly      Read more         Source

April 10, 2008, 8:09 PM CT

And the First Animal on Earth Was a ....

A new study mapping the evolutionary history of animals indicates that Earth's first animal--a mysterious creature whose characteristics can only be inferred from fossils and studies of living animals--was probably significantly more complex than previously believed.

The study, which was funded by the National Science Foundation (NSF), is the cover story of the April 10, 2008 issue of Nature Using new high-powered technologies for analyzing massive volumes of genetic data, the study defined the earliest splits at the base of the animal tree of life. The tree of life is a hierarchical representation of the evolutionary relationships between species that was introduced by Charles Darwin. (See diagram.

Shaking Up the Tree of Life

Among the study's surprising findings is that the comb jelly split off from other animals and diverged onto its own evolutionary path before the sponge. This finding challenges the traditional view of the base of the tree of life, which honored the lowly sponge as the earliest diverging animal. "This was a complete shocker," says Dunn. "So shocking that we initially thought something had gone very wrong.".

But even after Dunn's team checked and rechecked their results and added more data to their study, their results still suggested that the comb jelly, which has tissues and a nervous system, split off from other animals before the tissue-less, nerve-less sponge......... Posted by: Kelly      Read more         Source

April 3, 2008, 8:42 PM CT

DNA analysis of California wolverine

Preliminary results from DNA analysis of wolverine scat samples collected on the Tahoe National Forest do not match those of historic California wolverine populations, as per U.S. Forest Service scientists.

Geneticists with the agencys Rocky Mountain Research Station recently began analyzing samples, when wildlife biologists with the Tahoe National Forest and California Department of Fish and Game began sending hair and scat samples they collected from wolverine detection sites on the national forest to a lab in Missoula, Mont.

The interagency effort began in March after an Oregon State University graduate student working on a cooperative project with the U.S. Forest Services Pacific Southwest Research Station photographed a wolverine, an animal whose presence has not been confirmed in California since the 1920s.

DNA analysis is critical to researchers working to determine if the animal first photographed on February 28 and in later detection work is a wolverine that dispersed from outside of California, escaped from captivity or is part of a historic remnant population.

Key findings from the preliminary analysis indicate the animal in the photographs is a male wolverine that is not a descendent of the last known Southern Sierra Nevada population, said Bill Zielinski, a Forest Service scientist with the Pacific Southwest Research Station and an expert at detecting wolverine, marten and fisher. It also does not genetically match populations in Washington, he said......... Posted by: Kelly      Read more         Source

April 3, 2008, 8:38 PM CT

Asian waterbirds stage remarkable comeback

NEW YORK (April 3, 2008) As per a report released recently by the Wildlife Conservation Society (WCS), several species of rare waterbirds from Cambodias famed Tonle Sap region have staged remarkable comebacks, thanks to a project involving a single team of park rangers to provide 24-hour protection to breeding colonies. The project pioneered a novel approach: employing former hunters and egg collectors to protect and monitor the colonies, thereby guaranteeing the active involvement of local communities in the initiative.

The report suggests that some species, which include varieties of storks, pelicans, and ibises, have rebounded 20-fold since 2001, when WCS and the Ministry of Environment of the Royal Government of Cambodia established the conservation project. Before that time, rampant harvesting of both eggs and chicks had driven the colonies to the brink of local extinction.

"This is an amazing success story for the people and wildlife of Cambodia," said Colin Poole, Wildlife Conservation Society director for Asia Programs. "It also shows how important local people are in the conservation of wildlife in their own backyards".

Scientists first discovered the colonies in the mid 1990s in Prek Toal, an area within the massive Tonle Sapa seasonally flooded wetland critical to Cambodias people and wildlife. According WCS researchers, the colonies include the largest, and in some cases, the only breeding populations of seven Globally Threatened large waterbird species in Southeast Asia......... Posted by: Kelly      Read more         Source

April 3, 2008, 8:36 PM CT

Hatchery fish outnumber wild chinook salmon

A recent study indicates that wild salmon may account for just 10 percent of California's fall-run chinook salmon population, while the vast majority of the fish come from hatcheries. The findings are particularly troubling in light of the disastrous decline in the population this year, which will probably force the closure of the 2008 season for commercial and recreational salmon fishing.

The role of hatcheries in the management of salmon populations has been a contentious issue for a number of years. The new findings appear to support the idea that including artificially propagated fish in population estimates can mask declines in natural populations caused by a lack of suitable habitat.

"Our finding that 90 percent of the fish are from hatcheries surprised a lot of people," said Rachel Barnett-Johnson, a fisheries biologist with the Institute of Marine Sciences at the University of California, Santa Cruz.

Barnett-Johnson and her coworkers published their results in the December 2007 issue of the Canadian Journal of Fisheries and Aquatic Sciences. The main focus of the paper is the development of a new technique for distinguishing between wild and hatchery-raised salmon. The scientists validated the technique and used it to estimate the percentage of wild fish among the fall-run chinook salmon caught by commercial fishing boats along the central California coast in 2002......... Posted by: Kelly      Read more         Source

April 3, 2008, 8:03 PM CT

Role of bats in plant protection

Scientists at the Smithsonian Tropical Research Institute report that bats significantly reduce insect abundance and damage on plants. In a lowland tropical rainforest in Panama, bats can consume roughly twice as a number of plant-eating insects as do birds. This landmark study in the journal Science is the first to compare the ability of bats and birds to protect plants via insect predation in a natural forest ecosystem.

A prior study by the authors suggested that bats were underestimated predators of plant eating insects, based on video recordings of feeding events.

In the current study, Smithsonian short-term fellow Margareta Kalka, and co-authors Elisabeth Kalko, institute staff scientist and professor at the Institute of Experimental Ecology at the University of Ulm, and Smithsonian postdoctoral fellow Adam Smith, separated the insect-control effects of bats and birds by placing netting enclosures over five common tropical plant species only at night or only by day. Uncovered control plants accessed by both bats and birds lost merely 4.3 percent of their leaf area to insect herbivores. When only birds were excluded, plants lost 7.2 percent of their leaf area. When only bats were excluded, plants lost a striking 13.3 percent of their leaf area, demonstrating that in the tropical forest understory bats can be more effective pest control agents than birds......... Posted by: Kelly      Read more         Source

April 3, 2008, 7:39 PM CT

Are animals stuck in time?

Dog owners, who have noticed that their four-legged friend seem equally delighted to see them after five minutes away as five hours, may wonder if animals can tell when time passes. Newly published research from The University of Western Ontario may bring us closer to answering that very question.

The results of the research, entitled "Episodic-Like Memory in Rats: Is it Based on When or How Long Ago," appear in the current issue of the journal Science, which was released recently.

William Roberts and colleagues in Western's Psychology Department observed that rats are able to keep track of how much time has passed since they discovered a piece of cheese, be it a little or a lot, but they don't actually form memories of when the discovery occurred. That is, the rats can't place the memories in time.

The research team, led by Roberts, designed an experiment in which rats visited the 'arms' of a maze at different times of day. Some arms contained moderately desirable food pellets, and one arm contained a highly desirable piece of cheese. Rats were later returned to the maze with the cheese removed on certain trials and with the cheese replaced with a pellet on others.

All told, three groups of rats were tested in the research using three varying cues: when, how long ago or when plus how long ago......... Posted by: Kelly      Read more         Source

April 2, 2008, 10:04 PM CT

Gypsy Moth Management Made More Efficient

A computer model that provides land managers with a more efficient and cost-effective approach for controlling gypsy moths and other invasive pests has been created by biologists at Penn State University and the University of Cambridge in the United Kingdom. Gypsy moths, which were introduced to North America in the late 1860s, are responsible for the defoliation of over a million acres of forest land each year and the loss of tens of millions of dollars. In a paper would be published later this month (April 2008) in the journal Ecological Applications, the team's results indicate that the best strategies for managing the destructive pests include eradicating medium-density infestations and reducing high-density infestations, rather than reducing spreading from the main infestation.

"Our model is state dependent, which means that it recommends different management strategies depending on the situation," said Katriona Shea, Penn State associate professor of biology and the team's leader. "Most managers currently use the same strategy in all situations, but our model suggests that by tailoring their approach to a particular situation, managers can be more effective in slowing the spread of invasive species".

Saving time and money is of the utmost importance with gypsy moths, which have by now spread throughout the northeastern United States and into the Midwest. "Some people argue that it's just a matter of time before the moths spread across the entire United States, so why bother trying to slow them down?" said Shea. "But we see it differently. We hope that by slowing their spread we can buy some time to find a better way to deal with them"......... Posted by: Kelly      Read more         Source

April 2, 2008, 10:01 PM CT

New fish has a face even Dale Chihuly could love

A fish that would rather crawl into crevices than swim, and that may be able to see in the same way that humans do, could represent an entirely unknown family of fishes, says a University of Washington fish expert.

The fish, sighted in Indonesian waters off Ambon Island, has tan- and peach-colored zebra-striping, and rippling folds of skin that obscure its fins, making it look like a glass sculpture that Dale Chihuly might have dreamed up. But far from being hard and brittle like glass, the bodies of these fist-sized fish are soft and pliable enough to slip and slide into narrow crevices of coral reefs. Its probably part of the reason that they've typically gone unnoticed until now.

The individuals are undoubtedly anglerfishes, says Ted Pietsch, a UW professor of aquatic and fishery sciences who has published 150 scholarly articles and several books on anglerfishes and is the world's leading authority on them. In the last 50 years researchers have described only five new families of fishes and none of them were even remotely correlation to anglerfishes, Pietsch says.

Husband and wife Buck and Fitrie Randolph, with dive guide Toby Fadirsyair, found and photographed an individual Jan. 28 in Ambon harbor. A second adult has since been seen and two more small, and obviously juveniles were spotted March 26, off Ambon. One of the adults laid a mass of eggs, just spotted Tuesday......... Posted by: Kelly      Read more         Source

Mon, 31 Mar 2008 00:30:18 GMT

Itch Cat Scratch Pad

Everytime you look at the tattered corners of your sofa, your shredded curtains or claw marks on the lovely kitchen cabinets, don''t you wish that your kitty didn''t have claws? Why not make your feline happy by providing a stylish alternative for her scratching instinct?

The people who designed the Itch Cat Scratch Pad had just that in mind. And while they were at it, they made it completely environment friendly too. Made from 100% renewable bamboo, the pads can be hung up (or placed horizontally) at strategic locations in your home to entice your kitty. The pads have removable carpet inserts that can be replaced from time to time. Sounds purrfect? Get yours from SquareCatHabitat for $50 a piece.

Via Eco Fling. Posted by: Sarah      Read more     Source

Sun, 30 Mar 2008 22:55:53 GMT

Killer Fish Terrifies Britain

A savage fish more terrifying than a piranha has been caught in Britain for the first time - sparking fears of a deadly invasion. The vicious giant snakehead eats everything it comes across and has even been reported to kill people.

The monster - from south-east Asia - has a mouth crammed with fearsome teeth, can ''crawl'' on land and survive out of water for up to four days. It is feared the fish had been smuggled in for an aquarium and then illegally released. Posted by: Gerard      Read more     Source

March 27, 2008, 9:28 PM CT

Small desert beetle found to engineer ecosystems

The mesquite girdler Oncideres rhodosticta may only be 13mm long, but it has a big role in shaping the landscape. Research carried out by Benjamin Duval and Walter Whitford at New Mexico State University has revealed that the beetle is speeding up the degradation of grasslands in the Chihuahua desert, the landscape so stunningly depicted in this years Oscar-winning film No Country for Old Men.

The mesquite girdler does this by regulating the growth of the mesquite shrub, ensuring their offspring have a plentiful supply of food. The beetles chew girdles around the older stems of the shrub, which forces the plant to regrow new stems the following year. The new stems supply the beetle larvae with food, but the mesquite shrub takes more nutrients from the soil for its increased growth, leaving less for the other plant species such as grasses.

Up to 150 years ago, the North Chihuahuan Desert was completely covered in grassland. The picture today is very different dunes and mesquite shrubs cover much of the landscape.

Duval said: Eventhough the desertification process was likely started by overgrazing cattle, the ecosystem engineering impact of the mesquite girdler could finish off the process......... Posted by: Kelly      Read more         Source

March 27, 2008, 9:11 PM CT

'Wildcat Power Cord' repairs cruciate ligament

An 8-year-old Jersey dairy cow is back at her Kansas farm thanks to a decade of research and an experimental surgery performed at Kansas State University's Veterinary Medical Teaching Hospital.

The cow, named Wilhelmina Jolene by the veterinary students assigned to her case, sustained a breeding injury in December 2007 when the cruciate ligament in her right knee ruptured. Dr. David Anderson, professor and head of agricultural practices at K-State's College of Veterinary Medicine, replaced the ligament using synthetic material called monofilament nylon. The procedure's success could have enormous implications for breeding quality cows and bulls with the same injury.

Fortunately, Wilhelmina's owner recognized the value of saving her. Mike Frey is the son of Dr. Russ Frey, a prominent professor at K-State's College of Veterinary Medicine. "She's owned by the son of an important faculty member in our college's history," Anderson said. "It's wonderful that there is a connection to Dr. Frey with this case and that Mike understands the teaching value."

Mike Frey said he was happy to be part of an effort that could help animals, producers and students.

"I was always under the assumption that an animal with this problem was going to be heading down the road," he said. "If they could perfect this so that a cow could be kept in production, that would be worth quite a bit"......... Posted by: Kelly      Read more         Source

March 25, 2008, 7:56 PM CT

Pepper Spray For Deterring Bears

Hikers and campers venturing into bear country this spring may be safer armed with 8-ounce cans of bear pepper spray than with guns, as per a new study led by a Brigham Young University bear biologist.

Thomas S. Smith, associate professor of wildlife science, has conducted field work among bears for 16 years and has never used bear spray, eventhough he carries it faithfully. "I wish I had more scary stories to share, but I've behaved myself," said Smith, emphasizing that caution and wisdom are the best way to prevent bear attacks.

Concerned about hikers' and campers' persistent doubts that a small can of liquid pepper spray could stop half a ton of claws, muscle and teeth, Smith and his colleagues analyzed 20 years of bear spray incidents in Alaska, home to 150,000 bears. He observed that the spray effectively halted aggressive bear behavior in 92 percent of the cases, whether that behavior was an attack or merely rummaging for food. Of all 175 people involved in the incidents studied, only three were injured by bears, and none mandatory hospitalization. Smith and his research team report their findings in the recent issue of the Journal of Wildlife Management.

"People working or recreating in bear habitat should feel confident they are safe if carrying bear spray," Smith said......... Posted by: Kelly      Read more         Source

March 24, 2008, 8:38 PM CT

A fly's tiny brain may hold huge human benefits

COLUMBIA, Mo. Before swatting at one of those pesky flies that come out as the days lengthen and the temperature rises, one should probably think twice. A University of Missouri researcher has found, through the study of Drosophila (a type of fruit fly), that by manipulating levels of certain compounds linked to the circuitry of the brain, key genes correlation to memory can be isolated and tested. The results of the study may benefit human patients suffering from Parkinsons disease and could eventually lead to discoveries in the therapy of depression.

The implication for human health is that it could influence our understanding of the cognitive decline linked to Parkinsons disease and depression in humans, said Troy Zars, MU assistant professor of biological science in the College of Arts and Science.

The idea that animals have a system that can match the quality of a memory with the significance of the memory is well established. If the event is significant, the memory and detail surrounding it is much stronger, lasts longer and is more easily recalled in comparison to more insignificant or common events. The problem the study addresses is the understanding of the mechanism by which that occurs.

We have developed a strategy to address how this matching occurs, so we can turn that crank over and over again. It allows us to answer the questions, What gene is it" How does it function" How does it interact with other proteins" We can find brand-new, completely unexpected things, Zars said......... Posted by: Kelly      Read more         Source

March 24, 2008, 7:36 PM CT

Ants as fungus farmers

It turns out ants, like humans, are true farmers. The difference is that ants are farming fungus.

Entomologists Ted Schultz and Sen Brady at the Smithsonians National Museum of Natural History have published a paper in the March 24 issue of the journal Proceedings of the National Academy of Sciences, providing new insight into the agricultural abilities of ants and how these abilities have evolved throughout time. Using DNA sequencing, the researchers were able to construct an evolutionary tree of fungus-growing ants, which revealed a single pioneering ancestor that discovered agriculture approximately 50 million years ago.

In the past 25 million years, four different specialized agricultural systems have evolved, leading to the most recently evolved and best-known fungus-growing ant speciesleaf-cutter ants. The ants do not eat the leaves; they grow their fungus gardens on them and then eat the fungus. By studying the agricultural evolution of leaf-cutter ants, as well as various other species, researchers may be able to develop improved human agricultural and medical methods.

Agriculture is very rare in the animal world, said Schultz. We only know of four animal groups that have discovered agriculture: ants, termites, bark beetles and humans. By studying certain fungus-growing ants, which our study indicates are almost like living fossils, we might be able to better understand steps involved in the evolution of ant agriculture......... Posted by: Kelly      Read more         Source

March 20, 2008, 7:15 PM CT

Deadly genetic disease prevented before birth

By injecting a customized "genetic patch" into early stage fish embryos, scientists at Washington University School of Medicine in St. Louis were able to correct a genetic mutation so the embryos developed normally.

The research could lead to the prevention of up to one-fifth of birth defects in humans caused by genetic mutations, as per the authors.

Erik C. Madsen, first author and an M.D./Ph.D. student in the Medical Scientist Training Program at Washington University School of Medicine, made the groundbreaking discovery using a zebrafish model of Menkes disease, a rare, inherited disorder of copper metabolism caused by a mutation in the human version of the ATP7A gene. Zebrafish are vertebrates that develop similarly to humans, and their transparency allows scientists to observe embryonic development.

Children who have Menkes disease have seizures, extensive neurodegeneration in the gray matter of the brain, abnormal bone development and kinky, colorless hair. Most children with Menkes die before age 10, and therapy with copper is largely ineffective.

The research is published this month in the Proceedings of the National Academy of Sciences' advance online edition.

The development of organs in the fetus is nearly complete at a very early stage. By that time, the mutation causing Menkes disease has already affected brain and nerve development......... Posted by: Kelly      Read more         Source

March 18, 2008, 9:08 PM CT

Conditions for Spanish brown bears

Brown bears from the Iberian Peninsula are not as genetically different from other brown bears in Europe as was previously thought. An international study being published this week in Proceedings of the National Academy of Sciences, PNAS, shows that, on the contrary, the Spanish bear was only recently isolated from other European strains. These findings shed new light on the discussion of how to save the population of Spanish bears.

The scientists extracted DNA and determined the gene sequence of bears from prehistoric material, primarily from the Iberian Peninsula. Some of the material was as much as 80,000 years old. When the data material was analyzed, what emerged was a totally unexpected pattern.

We expected to be able to follow the Spanish brown bear far back in time, but we found to our amazement that it had genetic material from bears in other parts of Europe. In fact, it seems that the Spanish bear was isolated for the first time in our own time, says doctoral student Cristina Valdiosera, who performed most of the laboratory and analytical work.

These bears have possibly been isolated in Spain for a few thousand years, which is a very short period in an evolutionary perspective. In other words, there has been a flow of genes to and from the Iberian Peninsula throughout most of the time brown bears have been there. This is extremely interesting data when we discuss transporting bears from other areas to Spain for the purpose of preservation, says Anders Gtherstam, who directed the study......... Posted by: Kelly      Read more         Source

March 17, 2008, 10:22 PM CT

Hissing Cockroaches Are Popular

Their gentle nature, large size, odd sounds and low-maintenance care have made Madagascar hissing cockroaches popular educational tools and pets for years. But the giant insects also have one unfortunate characteristic: Their hard bodies and feces are home to a number of mold species that could be triggering allergies in the kids and adults who handle the bugs, as per a new study.

Scientists have identified 14 different types of mold on and around this species of cockroach, including several molds linked to allergies and others that can cause secondary infections if they enter the lungs or an open wound.

"This is mainly a point of public awareness," said Joshua Benoit, lead author of the study and a doctoral candidate in entomology at Ohio State University. "We are not criticizing their use. We are just saying that if you handle these cockroaches, you should wash your hands when you're done.

"It's also best to maintain the cage. It's not a pet you can ignore," he said. "Without regular cleaning, feces will build up, and the old exoskeletons they shed will build up. And that's where a lot of the problems happen".

The research is reported in the recent issue of the journal Mycoses.

The natural life of the Madagascar hissing cockroach, or Gromphadorhina portentosa, is not well understood. But in captivity, the insects thrive on dog food and fruit, reproduce plentifully and do not bite. They grow to between 2 and 3 inches long and 1 inch wide, and will make their characteristic hissing sound if they are squeezed or otherwise feel threatened......... Posted by: Kelly      Read more         Source

March 17, 2008, 10:19 PM CT

Asia's odd-ball antelope faces migration crisis

Take a deers body, attach a camels head and add a Jimmy Durante nose, and you have a saiga the odd-ball antelope with the enormous schnoz that lives on the isolated steppes of Central Asia. Unfortunately, they are as endangered as they are strange-looking due to over-hunting. Now, as per a recent Wildlife Conservation Society study, their migration routes are in jeopardy as well.

The study, which appears in the latest issue of The Open Conservation Biology Journal, tracked saiga with GPS collars in Mongolia and discovered a migration bottleneck a narrow corridor of habitat that connects two populations. The authors say that the corridor, which spans just three miles wide, is threatened by herders with livestock, along with increased traffic from trucks and motorcycles.

Like other species of the steppes and deserts, saiga have avoided extinction by being able to migrate long distances as their habitat changed over time, said Dr. Joel Berger, a Wildlife Conservation Society conservationist, and professor at the University of Montana. Given the uncertainty of how global climate change might affect specific regions, and how and where species might persist, prudent conservation strategies must take into account the movements of highly mobile species like saiga......... Posted by: Kelly      Read more         Source

March 17, 2008, 10:15 PM CT

Like sweets?

As per scientists at the Monell Center, fruit flies are more like humans in their responses to a number of sweet tastes than are almost any other species.

The diverse range of molecules that humans experience as sweet do not necessarily taste sweet to other species. For example, aspartame, a sweetener used by humans, does not taste sweet to rats and mice.

However, fruit flies respond positively to most sweeteners preferred by humans, including sweeteners not perceived as sweet by some species of monkeys.

The findings, reported in the current issue of the journal Chemical Senses, demonstrate the critical role of environment in shaping the genetic basis of taste preferences and feeding behavior.

Humans and flies have similar taste responses because they share similar environments and ecological niches, not because their sweet receptors are similar genetically, notes senior author Paul A.S. Breslin, PhD, a Monell sensory geneticist. Both are African species, both are omnivorous, and both historically are primarily fruit eaters.

To compare how molecular structure is correlation to sweet taste perception in humans and flies, the Monell scientists reviewed how fruit flies respond to 21 nutritive and nonnutritive compounds of varying molecular structure, all of which taste sweet to humans......... Posted by: Kelly      Read more         Source

March 17, 2008, 10:09 PM CT

Zebrafish enables cell regeneration studies

One aquarium fish's uncanny ability to regenerate essentially any cell type has given researchers a way to mimic cell loss that occurs in diseases such as Parkinson's and diabetes then watch how the fish make more of them.

"What we are pinning everything on is the idea that humans also have this capacity, but it's sort of locked up," says Dr. Jeff S. Mumm, biologist at the Medical College of Georgia.

Dr. Mumm, along with his partner in science and life, Dr. Meera Saxena, founded the company, Luminomics, Inc., to help fellow researchers unlock that capacity. "The forefront of medicine is not what humans are limited to, but what biology can do," says Dr. Mumm. "This little fish is telling us what biology is capable of. With the same general set of genetic tools, these animals can do something we can't: regenerate lost cells and tissues. Our job is to figure out which tools in which combination or sequence afford fish this capacity, then apply this knowledge toward the creation of regenerative therapies for humans".

While working as a postdoctoral fellow at Washington University in St. Louis, Dr. Mumm used the resilient zebrafish to study retinal development. As a student at the University of Iowa, he studied the regeneration of olfactory receptor neurons, which enable the sense of smell. They are one of the few neuronal populations that regenerate throughout life in mammals: the usual human response to lost neurons is scarring and disease......... Posted by: Kelly      Read more         Source