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May 27, 2008, 10:24 PM CT

What makes life go at the tropics?

What makes life go at the tropics?
What causes tropical life to thrive: temperature, or sunlight?

The answer is not necessarily both. As per a research studypublished online this week in PNAS Early Edition, the explosion of species at the tropics has much more to do with warmth than with light.

The diversity was uncorrelation to productivity (from photosynthesis), but it was strongly correlation to temperature, said University of Southern California biologist Jed Fuhrman, who led a group that analyzed bacterial samples from warm and cold oceans.

Fuhrmans group found far greater diversity in samples taken near the equator. In particular, samples from low-productivity waters still contained a number of bacterial species, suggesting that photosynthesis has little influence on diversity.

A number of scientists have tried to separate the influence of temperature and sunlight, Fuhrman said, but have found it hard to do by studying higher organisms.

Bacteria are ideal subjects because of their wide distribution and the recent availability of genetic fingerprinting, he added.

The question of what drives diversity is important to biologists who seek to uncover the basic rules governing life.

Is diversity ruled by fundamental laws, and if so, what is the basis of them? Fuhrman asked.........

Posted by: Erica      Read more         Source


May 27, 2008, 10:09 PM CT

Healthy Parents Provide Clues to Survival of Young Haddock

Healthy Parents Provide Clues to Survival of Young Haddock
Scientific crew sorts haddock during the NEFSC autumn bottom trawl survey cruise aboard the NOAA research vessel Albatross IV in 2003. (Credit: NOAA)
In 2003, haddock on Georges Bank experienced the largest baby boom ever documented for the stock, with an estimated 800 million new young fish entering the population. With typical annual averages of 50 to 100 million new fish in the last few decades, fisheries biologists have been puzzled by the huge increase and its ramifications for stock management. They have been looking for answers and may have found one - healthy adults.

In a study would be reported in the recent issue of the Canadian Journal of Fisheries and Aquatic Sciences, Dr. Kevin Friedland and his colleagues from NOAA's National Marine Fisheries Service and the University of Massachusetts suggest that the successful 2003 recruitment year is correlation to the fall phytoplankton bloom the year before spawning, and to the condition of the adult haddock. Phytoplankton, microscopic marine plants, form the basis of the ocean food web, and are the main source of food for a number of fish and other animals in the ocean. The fall 2002 bloom was significant, providing a larger than usual source of food for the ecosystem.

"Simply put, having more food to eat gives adult haddock a chance to get into better physical shape to reproduce healthy offspring with a higher chance of survival," says Friedland, a research scientist at NOAA Fisheries' Northeast Fisheries Science Center. "We evaluated the usually applied factors that control recruitment, and observed that the fall phytoplankton bloom the year before seems to link parental condition with a good recruitment. We call this new approach the parental condition hypothesis".........

Posted by: Kelly      Read more         Source


May 27, 2008, 9:34 PM CT

The secret behind silkworm's hardy stomachs

The secret behind silkworm's hardy stomachs
Silkworm eating mulberry leaf.

Credit: Toru Shimada

Silkworms have a unique ability to eat toxic mulberry leaves without feeling ill, and scientists have come one step closer to understanding why: silkworms contain a special digestive enzyme that is not affected by mulberrys toxic chemicals.

Mulberry leaves contain an extremely high amount of alkaloids that inhibit enzymes that break down sucrose (sugar), and thus are potentially quite toxic. However, one type of sucrase called beta-fructofuranosidase is not affected by these alkaloids.

Until now, this enzyme has not been found in any animals, but Toru Shimada and his colleagues believed this might explain the silkworms unique diet.

The scientists scanned the silkworm genome and discovered two fructofuranosidase genes, eventhough only one was actually expressed in the worm. This gene (BmSuc1) was, as expected, concentrated in the worms gut, eventhough surprisingly was also prevalent in the silk gland. When they isolated the enzyme from silkworms, the scientists found it could effectively digest sucrose.

Shimada and his colleagues note that further work is needed to determine if this special enzyme is the sole reason for silkworms resistance to mulberry toxins. Its possible that fructofuranosidases may turn up in other insects that cannot eat mulberry leaves, indicating additional factors are at work.........

Posted by: Kelly      Read more         Source


May 22, 2008, 10:30 PM CT

Over 50 percent of oceanic shark species threatened with extinction

Over 50 percent of oceanic shark species threatened with extinction
22nd May 2008 The first study to determine the global threat status of 21 species of wide-ranging oceanic pelagic sharks and rays reveals serious overfishing and recommends key steps that governments can take to safeguard populations. These findings and recommendations for action are reported in the latest edition of Aquatic Conservation: Marine and Freshwater Ecosystems.

This international study, organised by the IUCN Shark Specialist Group (SSG), was conducted by 15 researchers from 13 different research institutes around the world, with additional contributions from scores of other SSG members.

The experts determined that 16 out of the 21 oceanic shark and ray species that are caught in high seas fisheries are at heightened risk of extinction due primarily to targeted fishing for valuable fins and meat as well as indirect take in other fisheries. In most cases, these catches are unregulated and unsustainable. The increasing demand for the delicacy shark fin soup, driven by rapidly growing Asian economies, means that often the valuable shark fins are retained and the carcasses discarded. Frequently, discarded sharks and rays are not even recorded.

Sharks and rays are especially vulnerable to overfishing due to their tendency to take a number of years to become sexually mature and have relatively few offspring.........

Posted by: Kelly      Read more         Source


May 22, 2008, 10:20 PM CT

New family of gecko discovered

New family of gecko discovered
Marbled Gecko
Photo Courtesy Ben Moulton
Scientists at the University of Minnesotas Bell Museum of Natural History and Pennsylvanias Villanova University have discovered a new family of gecko, the charismatic large-eyed lizard popularized by car insurance commercials.

Researchers have long been interested in geckos and their evolution because they are key biodiversity indicators and are found on nearly every continent. Scientists are also interested in the gecko because of the animals sticky toe pads, which allow them to scale rough and smooth surfaces -- a characteristic that may have human application in medicine, emergency rescue service and military industries.

Graduate students Tony Gamble from the University of Minnesota and Aaron Bauer from Villanova sequenced DNA from 44 species of gecko and used this genetic data to reconstruct the animals family tree. The resulting new classification is different from prior classifications, which are based solely on foot structure.

A classification based solely on foot structure will track selective pressure on the feet and not represent actual evolutionary history, said Gamble, who believes his discovery will add to a more accurate gecko family tree that, in turn, will allow researchers to better understand how sticky toe pads have evolved.

The scientists have named the new family Phyllodactylidae, referring to the leaf-shaped toes of a number of of the species in this group (phyllo meaning leaf: dactyl meaning toe). The new family consists of 103 species found in semiarid and tropical regions of North Africa, the Middle East, North and South America and the Caribbean.........

Posted by: Kelly      Read more         Source


May 21, 2008, 8:54 PM CT

Relocation of endangered Chinese turtle

Relocation of endangered Chinese turtle
Conservationists hoping to save the Yangtze giant softshell turtle from extinction are hoping that this female (basking beside the water's edge) will mate with the only known male of the species (in the water).

Credit: Gerald Kuchling/TSA
There are only four specimens of the Yangtze giant softshell turtle left on Earthone in the wild and three in captivity. In order to save this species from extinction, conservation partners from the Wildlife Conservation Society (WCS) and the Turtle Survival Alliance (TSA), working in conjunction with partners from two Chinese zoos and the China Zoo Society, recently paired two of them. A still reproductive, more than 80-year-old, female, living in Chinas Changsha Zoo has been introduced to the only known male in China, a more than 100-year-old living more than 600 miles away at the Suzhou Zoo.

The Bronx Zoo-based WCS and the Fort Worth Zoo-based TSA coordinated the critically important move; TSA provided much of the funding, animal reproduction and technical expertise while WCS provided veterinary and logistical support and coordination with wildlife partners in China and New York. Other project partners include Ocean Park and Kadoorie Farm and Botanic Garden, both in Hong Kong.

On Monday, May 5, turtle biologists, veterinarians, and zoo staff from partner organizations convened at the Changsha Zoo to collect and transport the female to the Suzhou Zoo where she joined her new mate to potentially save their entire species. The move was coordinated to coincide with the females reproductive cycle.........

Posted by: Kelly      Read more         Source


May 21, 2008, 8:39 PM CT

North Pacific humpback whale populations rebounding

North Pacific humpback whale populations rebounding
NOAA ship Oscar Dyson stands watch as researchers gather information from humpback whales. Humpback whale flukes, like the one shown here, are unique to each animal just like a fingerprint. This whale could be identified thousands of miles away by its distinctive markings.

Credit: NOAA


The number of humpback whales in the North Pacific Ocean has increased since international and federal protections were enacted in the 1960s and 70s, as per a new study funded primarily by NOAA and conducted by more than 400 whale scientists throughout the Pacific region.

However, some isolated populations of humpbacks, particularly those in the Western Pacific Ocean, have not recovered at the same rate and still suffer low numbers.

The new research reveals that the overall population of humpbacks has rebounded to approximately 18,000 to 20,000 animals. The population of humpback whales in the North Pacific, at least half of whom migrate between Alaska and Hawaii, numbered less than 1,500 in 1966 when international whaling for this species was banned. In the 1970s, federal laws including the Marine Mammal Protection Act and the Endangered Species Act provided additional protection.

NOAA is proud to have played a key role in initiating and funding this study, said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. It is only through this type of international cooperation that we can gauge our success and measure what additional work needs to be accomplished to protect highly migratory marine mammals.........

Posted by: Kelly      Read more         Source


May 20, 2008, 9:36 PM CT

Scientists Discover a Molecular Scaffold

Scientists Discover a Molecular Scaffold
Z. Josh Huang, Ph.D
Brain cells known as neurons process information by joining into complex networks, transmitting signals to each other across junctions called synapses. But "neurons don't just connect to other neurons," emphasizes Z. Josh Huang, Ph.D., "in a lot of cases, they connect to very specific partners, at particular spots."

Dr. Huang, a professor at Cold Spring Harbor Laboratory (CSHL), leads a team that has identified molecules guiding this highly specific neuronal targeting in the developing brains of mice. The scientists report in PLoS Biology that in some cases, these molecular guides -- non-signaling brain cells known as glia -- form a kind of scaffold. This scaffold, in turn, directs the growth of nerve fibers and their connections between specific types of neurons.

As they learn through research like this how the brain develops its complex wiring, the researchers hope they can clarify what goes wrong in disorders like autism.

The Cerebellum's 'Organized Architecture'.

Distinctive wiring patterns are unmistakable in the cerebellum, a brain region best known for controlling movement, in both mice and people. In comparison to regions involved in more sophisticated functions like vision and thought, "the cerebellum is an easier place to start, because of its very organized architecture," Dr. Huang says, eventhough he notes that other parts of the brain have their own specific wiring patterns.........

Posted by: Janet      Read more         Source


May 19, 2008, 8:19 PM CT

Children's gardens mushrooming

Children's gardens mushrooming
Scientists have discovered the secrets to enhancing youth participation in school- and community-based garden programs. A 3-year study entitled Greener Voices proves that children will engage in learning more readily when given responsibility for decisionmaking and planning.

Childrens gardens have mushroomed during the past two decades. Gardens are popping up in schools, communities, public venues, and informal settings. Despite recent interest in gardening with children, little credence has been given to what children think about the experience: what interests them, how they may be involved in decisionmaking and planning, and how they can benefit from their involvement. Adults make a number of assumptions about children and gardening, and instead of enlisting the creativity and innovative thinking of young people, they often involve children in the more mundane tasks of planting, weeding, and watering notes Marcia Eames-Sheavly, lead researcher and Senior Extension Associate at Cornell Universitys Garden-Based Learning Program (http://www.hort.cornell.edu/gbl).

Scientists set out to understand how children and youth engaged in project planning and to gain a better grasp of the constraints faced by adults who teach and design gardening programs. We learned that ongoing efforts are needed to assist sites and the adult leaders who work there, including strategies to expand thinking about the capabilities of children and youth, to help children and youth adjust to new roles, and to identify ways for younger children to increase their participation, added Eames-Sheavly.........

Posted by: Erica      Read more         Source


May 19, 2008, 7:48 PM CT

Greener offices make happier employees

Greener offices make happier employees
Growing plants in the office.

Credit: flora.cyclam
As per the 2000 census, Americans office workers spend an average of 52 hours a week at their desks or work stations. A number of recent studies on job satisfaction have shown that workers who spend longer hours in office environments, often under artificial light in windowless offices, report reduced job satisfaction and increased stress levels.

How can employers make office environments more conducive to productivity and employee happiness" Try adding some green to your office. Not greenbacksgreen plants! A research study reported in the February 2008 issue of HortScience offers employers and corporations some valuable advice for upping levels of employee satisfaction by introducing simple and inexpensive environmental changes.

Dr.Tina Marie (Waliczek) Cade, Associate Professor of Horticulture in the Department of Agriculture at Texas State University, explained that the project was designed to investigate whether employees who worked in offices with windows and views of green spaces and workers who had green plants in their offices perceived greater job satisfaction than employees who did not have access to these environmental components.

Scientists posted a job satisfaction survey on the Internet and administered the survey to office workers in Texas and the Midwest. The survey included questions about job satisfaction, physical work environments, the presence or absence of live interior plants and windows, environmental preferences of the office workers, and demographic information.........

Posted by: Erica      Read more         Source

   

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