Sun, 11 Mar 2007 18:25:08 GMT

Greenhouse Gas Stems Shell-making Ability of Oysters, Mussels by 10 to 25%

With the increase of carbon dioxide, a greenhouse gas, leading to global warming has been predicted with several devastating effects on the living earth. To add to the list of predicted destructions, global warming will have, or rather is already manifesting them, a new study has found that with the increase in the thickening of carbon dioxide by the year 2100 — oysters and mussels would not be able to make their shells in the way there are being able to now! And, this again is to be blamed on increase in carbon dioxide level or global warming.

The increase in the greenhouse gas leads to increase water acidity in turn. This increase in acidity stems the abilities of shellfishes to calcify shells by 10 to 25 percent. Its effect in the in coastal areas could be huge, both ecologically and economically, as it is where, shellfish play vital roles.

This finding is reported by Frederic Gazeau and his colleagues at the Netherlands Institute of Ecology, the French Centre National de la Recherche Scientifique and Universite Pierre et Marie Curie.

Coral researcher Chris Langdon of the University of Miami affirmed,

There hasn’t been any data before on this.

Photo Credit: Associated Press

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 published 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, Germany, where she is investigating how female lance-tailed manakins choose their mates......... Posted by: Ashley      Read more         Source

February 27, 2007, 9:38 PM CT

Light On Blue Whales And Their Calls

Using a variety of new approaches, scientists 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 researchers 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, researchers 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 researchers 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: Ashley      Read more         Source

February 26, 2007, 6:57 PM CT

Lost cuckoo breaks its silence

A team of biologists with the New York-based Wildlife Conservation Society (WCS) have recorded for the first time the call of the extremely rare Sumatran ground cuckoo, found only on the island of Sumatra in Indonesia.

The bird was captured by a trapper and handed over to WCS biologists, who recorded the birds call while it nursed an injured foot. Once fully recovered, the bird will be released back into the wild.

Known only by a handful of specimens collected over the past century, the Sumatran ground cuckoo is considered to be one of the worlds rarest, most secretive birds, and is restricted to Sumatras deep jungles and rainforests. In fact, ornithologists believed the bird was extinct until 1997, when a single individual was briefly seen. Last year a second bird was photographed by a remote camera trap. It is now believed to be critically endangered.

Until now, however, no one knew the birds call a key field diagnostic ornithologists use to identify birds that live in forest. According to WCS, having a recording of the birds call will also make it easier for biologists to locate other individuals, and to possibly evaluate the birds total population.

"We were extremely lucky to have recorded the birds unique call," said Firdaus Rahman, of WCSs Indonesia Program. "Our team will use the recording to hopefully locate other Sumatran ground cuckoos, and to eventually secure their protection"......... Posted by: Ashley      Read more         Source

February 21, 2007, 9:07 PM CT

Lizards 'shout' Against A Noisy Background

Lizards that signal to rivals with a visual display "shout" to get their point across, UC Davis researchers have found.

Male anole lizards signal ownership of their territory by sitting up on a tree trunk, bobbing their heads up and down and extending a colorful throat pouch. They can spot a rival lizard up to 25 meters away, said Terry Ord, a postdoctoral researcher at UC Davis who is working with Judy Stamps, professor of evolution and ecology.

The lizards' signals need to be strong enough for a rival to see, but not vivid enough to say "eat me" to a passing predator. But their forest home can be a visually noisy environment, with branches and leaves waving in the breeze and casting patterns of light and shade.

"They have to have a strategy to get their message across," Ord said.

Ord videotaped two species of anole lizards, Anolis cristatellus and Anolis gundlachi, in the Caribbean National Forest in Puerto Rico. He found that the more "visual noise" in the background, the faster and more exaggerated the movements of the lizards.

Anole lizards are interesting to evolutionary biologists because different species are found on different islands all over the Caribbean. The lizards are not particularly closely related -- they are separated by 30 million years of evolution -- but they live in similar environments with the same obstacles to communication. So Ord is using them as a model to investigate the evolution of such signals......... Posted by: Ashley      Read more         Source

February 11, 2007, 8:53 PM CT

Grape expectations for healthier wine

A new technique that uses ozone to preserve grapes could help prevent allergies and boost healthy compounds at the same time, reports Jennifer Rohn in Chemistry & Industry, the magazine of the SCI. The same technique could be used in the wine-making process to produce healthier wines without the added sulphites that can cause asthma and other conditions in some people.

Mass-marketed grapes can remain in storage for months and are usually treated with sulphur dioxide to prevent decay. Although the sulphur dioxide is effective, it is corrosive and can cause severe allergic reactions in some people. Wine-makers have a similar problem in that the sulphites added to wines to prolong their shelf-life and allow them to age can make their wines unpalatable to some drinkers.

Francisco Artes-Hernandez and his team at the Technical University of Cartagena in Spain compared several different preservative methods with a new technique that involves exposing macroperforated packages of grapes at 0 degress C to cycles of 0.1 micro liters per liter of ozone. They found that ozone treatment was 90% as effective as SO2 at preventing decay. In addition, ozone-treated grapes had up to four times more antioxidants than untreated grapes (Journal of the Science of Food and Agriculture, doi 10.1002/jsfa.2780).........

Posted by: Ashley      Read more         Source

February 9, 2007, 4:38 AM CT

Nanotechnology meets biology

The object of fascination for most is the DNA molecule. But in solution, DNA, the genetic material that hold the detailed instructions for virtually all life, is a twisted knot, looking more like a battered ball of yarn than the famous double helix. To study it, researchers generally are forced to work with collections of molecules floating in solution, and there is no easy way to precisely single out individual molecules for study.

Now, however, researchers have developed a quick, inexpensive and efficient method to extract single DNA molecules and position them in nanoscale troughs or "slits," where they can be easily analyzed and sequenced.

The technique, which as per its developers is simple and scalable, could lead to faster and vastly more efficient sequencing technology in the lab, and may one day help underpin the ability of clinicians to obtain customized DNA profiles of patients.

The new work is reported this week (Feb. 8, 2007) in the Proceedings of the National Academies of Science (PNAS) by a team of researchers and engineers from the University of Wisconsin-Madison.

"DNA is messy," says David C. Schwartz, a UW-Madison genomics researcher and chemist and the senior author of the PNAS paper. "And in order to read the molecule, you have to present the molecule".........

Posted by: Kevin      Read more         Source

February 7, 2007, 9:37 PM CT

Risk of extinction accelerated due to human

The simultaneous effect of habitat fragmentation, overexploitation, and climate warming could accelerate the decline of populations and substantially increase their risk of extinction, a study reported in the Proceedings of the Royal Society B has warned.

Using experimental microcosm populations of rotifers (a type of zooplankton), the study observed that individually each of these threats caused significant population declines. The study also observed that the rate of declines was much accelerated when populations were exposed to more than one threat. These results indicate that multiple interacting threats are capable of causing rapid population extinction, and that all threats should be simultaneously reduced, if their synergies are to be avoided and if the current rate of species loss is to be reversed.

A number of scientific efforts have been made to link the decline of wild marine and terrestrial populations with human activities such as habitat fragmentation, overexploitation and global warming. "Establishing the link between the loss of biodiversity and human-related threats is crucial to develop policies aimed at mitigating such threats", says Camilo Mora at Dalhousie University, leading author of the paper. "Unfortunately, in a number of cases several threats are operating simultaneously making it difficult to isolate their individual and combined effects through field observations,"Mora adds.........

Posted by: Ashley      Read more         Source

February 6, 2007, 9:53 PM CT

Are You My Mother?

Mama Fox can often be found with her kits, tossing tennis balls, crawling on her hands and knees in their playpen, and making a game out of chasing crickets. Even though "Mama" is a tailless, fur-less giant in comparison to the tiny fennec fox kits, the three youngsters have grown used to her parenting ways, and enjoy an afternoon nap in her lap.

Mama Fox is better known as Kathleen LaMattina, Animal Programs Liaison for the Wildlife Conservation Society's Bronx Zoo. Kathleen supervises and manages the Zoo's Tractable Animal Collection-a group of more than 300 animals that participate in education and outreach programs. The particularly social fennec foxes are among the zoo's best-loved animal ambassadors, often accompanying Bronx Zoo instructors to school programs, as well as meeting and greeting children and adults at zoo-based programs.

Fennec foxes aren't shy in a crowd. In their wild habitat, North Africa's Sahara Desert and the northern part of Saudi Arabia, these animals live in groups of up to ten individuals. Their bodies are well suited to the harsh conditions of their desert home-large ears enable them to get rid of excess body heat, fur on the soles of their paws help protect them from the hot sand, and buff-colored coats help them blend in.

Kit Kinder Care: Naptime, Playtime, and Hunting Lessons.........

Posted by: Ashley      Read more         Source

February 6, 2007, 9:29 PM CT

Man-made Proteins Could Be More Useful

Scientists have constructed a protein out of amino acids not found in natural proteins, discovering that they can form a complex, stable structure that closely resembles a natural protein. Their findings could help researchers design drugs that look and act like real proteins but won't be degraded by enzymes or targeted by the immune system, as natural proteins are.

The researchers, led by Howard Hughes Medical Institute (HHMI) professor Alanna Schepartz, report their findings in the February 14, 2007, issue of the Journal of the American Chemical Society, published in advance online on January 19, 2007. Schepartz and her coauthors, Douglas Daniels, James Petersson, and Jade Qiu, are all at Yale University. A story in the February 5, 2007, issue of Chemical & Engineering News spotlighted the research.

As an HHMI professor, Schepartz received a $1 million grant to find ways to infuse undergraduate teaching with the excitement of research. Several of her HHMI undergraduates synthesized beta-amino acid monomers that were used to prepare the synthetic protein.

Schepartz and his colleagues built the short protein, or peptide, from ß-amino acids, which, eventhough they exist in cells, are never found in ribosomally produced proteins. ß-amino acids differ from the alpha-amino acids that compose natural proteins by the addition of a single chemical component-a methylene group-into the peptide backbone.........

Posted by: Sarah      Read more         Source