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November 2, 2009, 10:56 PM CT

North Atlantic Fish Populations Shifting

North Atlantic Fish Populations Shifting
Map shows location of the study, in U.S. waters between Cape Hatteras, N.C., and the U.S.-Canadian border. (Credit: Chad Keith, NEFSC/NOAA)
About half of 36 fish stocks in the Northwest Atlantic Ocean, a number of of them commercially valuable species, have been shifting northward over the last four decades, with some stocks nearly disappearing from U.S. waters as they move farther offshore, as per a newly released study by NOAA researchers.

Their findings, reported in the journal Marine Ecology Progress Series, show the impact of changing coastal and ocean temperatures on fisheries from Cape Hatteras, N.C., to the Canadian border.

Janet Nye, a postdoctoral researcher at NOAA's Northeast Fisheries Science Center (NEFSC) laboratory in Woods Hole, Mass. and the main author of the study, looked at annual spring survey data from 1968 to 2007 for stocks ranging from Atlantic cod and haddock to yellowtail and winter flounders, spiny dogfish, Atlantic herring, and less well-known species like blackbelly rosefish. Historic ocean temperature records and long-term processes like the Atlantic Multidecadal Oscillation and the North Atlantic Oscillation dating back to 1850 were also analyzed to put the temperature data into context.

"During the last 40 years, a number of familiar species have been shifting to the north where ocean waters are cooler, or staying in the same general area but moving into deeper waters than where they traditionally have been found," Nye said. "They all seem to be adapting to changing temperatures and finding places where their chances of survival as a population are greater".........

Posted by: Kelly      Read more         Source


November 2, 2009, 8:44 AM CT

Moose eat plants; wolves kill moose

Moose eat plants; wolves kill moose
Moose eat plants; wolves kill moose. What difference does this classic predator-prey interaction make to biodiversity?

A large and unexpected one, say wildlife biologists from Michigan Technological University. Joseph Bump, Rolf Peterson and John Vucetich report in the November 2009 issue of the journal Ecology that the carcasses of moose killed by wolves at Isle Royale National Park enrich the soil in "hot spots" of forest fertility around the kills, causing rapid microbial and fungal growth that provide increased nutrients for plants in the area.

"This study demonstrates an unforeseen link between the hunting behavior of a top predatorthe wolfand biochemical hot spots on the landscape," said Bump, an assistant professor in Michigan Tech's School of Forest Resources and Environmental Science and first author of the research paper. "It's important because it illuminates another contribution large predators make to the ecosystem they live in and illustrates what can be protected or lost when predators are preserved or exterminated".

Bump and colleagues studied a 50-year record of more than 3,600 moose carcasses at Isle Royale. They measured the nitrogen, phosphorus and potassium levels in the soil at paired sites of wolf-killed moose carcasses and controls. They also analyzed the microbes and fungi in the soil and the leaf tissue of large-leaf aster, a common native plant eaten by moose in eastern and central North America.........

Posted by: Kelly      Read more         Source


November 2, 2009, 8:42 AM CT

Researchers sequence swine genome

Researchers sequence swine genome
Lawrence B. Schook, right, a professor of biomedical sciences at Illinois, with animal sciences professor Jonathan Beever. Schook, who is also an affiliate of the Institute for Genomic Biology at Illinois, led the international pig genome sequencing project, which has produced a draft of the pig genome.

Credit: Photo by L. Brian Stauffer, U. of I. News Bureau.

A global collaborative has produced a first draft of the genome of a domesticated pig, an achievement that will lead to insights in agriculture, medicine, conservation and evolution.

A red-haired Duroc pig from a farm at the University of Illinois will now be among the growing list of domesticated animals that have had their genomes sequenced. Scientists will announce the achievement Monday (Nov. 2) at a meeting at the Wellcome Trust Sanger Institute in Hinxton, England.

"The pig is a unique animal that is important for food and that is used as an animal model for human disease," said Larry Schook, a University of Illinois professor of biomedical sciences and leader of the sequencing project. "And because the native wild animals are still in existence, it is a really exciting animal to look at to learn about the genomic effects of domestication," he said.

The Duroc is one of five major breeds used in pork production around the world and is one of about 200 breeds of domesticated pigs. There are also numerous varieties of wild boar, the non-domesticated pigs that are believed to have originated in Eurasia.

The sequencing project involved an international team of researchers and.

genome-sequencing centers. The USDA National Institute of Food and Agriculture, formerly the Cooperative State Research, Education and Extension Service, provided $10 million in initial funding, requiring that this be the only pig genome-sequencing project in the world, that it be a public-private partnership and a global collaborative effort, with significant financial or in-kind support from the other participating agencies and stakeholders.........

Posted by: Kelly      Read more         Source


October 29, 2009, 10:07 PM CT

A heat sensor for body-clock synchronization

A heat sensor for body-clock synchronization
New research on the fruit-fly brain points to a possible mechanism by which temperature influences the body clock, as per researchers from Queen Mary, University of London.

Eventhough much is known about how light affects the body clock - also known at the circadian clock - it is not well understood which cells or organs sense daily temperature changes or how temperature signals reach the part of the brain that contains the circadian clock.

A variety of organisms, including insects and humans, have evolved an internal circadian clock to regulate patterns of behaviour throughout the day - for example sleep, appetite, alertness and concentration.

Senior study author Dr Ralf Stanewsky, from Queen Mary's School of Biological and Chemical Sciences, explains: "Given the substantial similarity between the fly and mammalian clock, our studies might also help to understand the human circadian clock and in the future perhaps contribute to developing therapys against the negative effects of sleep-disorders and shift-work".

Specially evolved "clock cells" in the brain contain the circadian clock, which needs to be synchronised with the natural environmental cycles every day to prevent them running too fast or too slow.

Dr Stanewsky and his colleagues have shown that fly brains were unable to synchronize to temperature cycles when separated from the rest of the body. This is in contrast with the ability to synchronize to light-dark cycles, which can take place with or without a connection to the fly body.........

Posted by: Kelly      Read more         Source


October 27, 2009, 9:57 AM CT

Environmental Impact Of Marine Fisheries

Environmental Impact Of Marine Fisheries
The Torres Strait Tropical Rock Lobster Fishery is one of more than 30 Australian fishing sectors to be assessed for its environmental impact using the Ecological Risk Assessment method.
Photo by: CSIRO
An Australian method for assessing the environmental impact of marine fisheries has caught the eye of fishery management agencies worldwide.

Aspects of the 'ecological risk evaluation' (ERA) method have been adopted in the US, Canada, Ecuador, and the Western and Central Pacific, and by the international eco-labelling organisation the Marine Stewardship Council.

The method was developed in research led by Dr Tony Smith and Dr Alistair Hobday from CSIRO's Wealth from Oceans Flagship in association with the Australian Fisheries Management Authority (AFMA).

"AFMA needed a tool for assessing the ecological risk linked to a diverse range of fishing practices: from the hand-selection of rock lobsters in the Coral Sea, to the trawling of Patagonian Toothfish deep in the Southern Ocean," Dr Smith says.

"We met the challenge with a three-step method that considers targeted and incidentally caught species, as well as threatened, endangered and protected species. Ongoing research is further developing the method for habitats and ecological communities.

"Each level of analysis potentially screens out issues of low concern and directs attention to higher risk issues. This helps fishery managers to guard against unacceptable changes to the ecosystem, while being strategic about where to focus dollars and time," Dr Smith says.........

Posted by: Kelly      Read more         Source


October 27, 2009, 9:54 AM CT

The skeleton: Size matters

The skeleton: Size matters
Vertebrates have in common a skeleton made of segments, the vertebrae. During development of the embryo, each segment is added in a time dependent manner, from the head-end to the tail-end: the first segments to be added become the vertebrae of the neck, later segments become the vertebrae with ribs and the last ones the vertebra located in the tail (in the case of a mouse, for example). In this process, it is crucial that, on the one hand, each segment, as it matures, becomes the correct type of vertebra and, on the other, that the number of vertebrae in the skeleton, and therefore the size of the spine, are minutely controlled.

It has long been known that the identity of each vertebra is due to the activation of a class of genes called Hox. Now, in the latest issue of Developmental Cell (*) scientists from the Instituto Gulbenkian de Cincia, in Portugal, the Institute KNAW and University Medical Centre (The Netherlands) show that besides determining the identity of the vertebrae, Hox genes also have a say in how a number of are going to be formed at all.

There is a huge diversity in number of vertebrae in animals: some have a number of vertebrae, and are thus longer, like a snake, and others have fewer vertebrae and are shorter, like mice. Vertebrae are made from precursors known as somites, formed in the embryos, sequentially from head to tail. This process is directly associated with growth of the embryo at its tail end: the more it grows, the more somites it makes and, as a result the more vertebrae the adult animal has. Of the a number of genes involved in this growth, a family of genes called Cdx are known to play a central role.........

Posted by: Kelly      Read more         Source


October 27, 2009, 9:52 AM CT

Charles Darwin's ideas about the origin of life

Charles Darwin's ideas about the origin of life
Charles Darwin really did have advanced ideas about the origin of life.

Credit: Armin Cifuentes

When Charles Darwin published The Origin of Species 150 years ago, he deliberately avoided the subject of the origin of life. This, coupled with the mention of the 'Creator' in the last paragraph of the book, led us to believe he was not willing to commit on the matter. An international team, led by Juli Peret of the Cavanilles Institute in Valencia, now refutes that idea and shows that the British naturalist did explain in other documents how our first ancestors could have come into being.

"All organic beings that have lived on Earth could be descended from some primordial form", explained Darwin in The Origin of Species in 1859. Despite this statement, the scientist took it upon himself to understand the evolutional processes underlying biodiversity.

"Darwin was convinced of the incredible importance of this issue for his theory and he had an amazingly modern materialist and evolutional vision about the transition of inanimate chemical matter into living matter, despite being very aware of Pasteur's experiments in opposition to spontaneous generation", Juli Peret, principal author of this study and researcher at the Cavanilles Institute of Evolutional Biology and Biodiversity at the University of Valencia, explains to SINC.

The study, which is reported in the latest issue of the journal Origins of Life and Evolution of Biospheres, demonstrates that Darwin had an advanced idea on the origin of the first species, and was troubled by the problem. "It is utterly wrong to believe that he was invoking a divine intervention; it is also well documented that the mention of the 'Creator' in The Origin of the Species was an addition for appearance's sake that he later regretted", affirms Peret.........

Posted by: Janet      Read more         Source


October 26, 2009, 7:36 AM CT

Mantis shrimps inspire technology

Mantis shrimps inspire technology
The remarkable eyes of a marine crustacean could inspire the next generation of DVD and CD players, as per a newly released study from the University of Bristol published recently in Nature Photonics

The mantis shrimps in the study are found on the Great Barrier Reef in Australia and have the most complex vision systems known to science. They can see in twelve colours (humans see in only three) and can distinguish between different forms of polarized light.

Special light-sensitive cells in mantis shrimp eyes act as quarter-wave plates which can rotate the plane of the oscillations (the polarization) of a light wave as it travels through it. This capability makes it possible for mantis shrimps to convert linearly polarized light to circularly polarized light and vice versa. Manmade quarter-wave plates perform this essential function in CD and DVD players and in circular polarizing filters for cameras.

However, these artificial devices only tend to work well for one colour of light while the natural mechanism in the mantis shrimp's eyes works almost perfectly across the whole visible spectrum from near-ultra violet to infra-red.

Dr Nicholas Roberts, main author of the Nature Photonics paper said: "Our work reveals for the first time the unique design and mechanism of the quarter-wave plate in the mantis shrimp's eye. It really is exceptional out-performing anything we humans have so far been able to create".........

Posted by: Kelly      Read more         Source


October 20, 2009, 10:19 PM CT

New method to help keep fruit and vegetables fresh

New method to help keep fruit and vegetables fresh
ATLANTA Did you know that millions of tons of fruits and vegetables in the United States end up in the trash can before being eaten, as per the U.S. Department of Agriculture?

A Georgia State University professor has developed an innovative new way to keep produce and flowers fresh for longer periods of time.

Microbiologist George Pierce's method uses a naturally occurring microorganism no larger than the width of a human hair to induce enzymes that extend the ripening time of fruits and vegetables, and keeps the blooms of flowers fresh. The process does not involve genetic engineering or pathogens, but involves microorganisms known to be linked to plants, and are considered to be helpful and beneficial to them.

"These beneficial soil microorganisms serve essentially the same function as eating yogurt as a probiotic to have beneficial organisms living in the gastrointestinal system," Pierce said.

The process works by manipulating the organism's diet so that it will over express certain enzymes and activities that work in the ripening process and keeping the flower blooms fresh. Pierce analogizes this to using diet and exercise to improve the performance of an athlete.

"We change the diet of the organism, and we can change its performance," Pierce said. "It's no different than taking a good athlete and putting them on a diet and exercise regime, and turning him or her into a world-class athlete".........

Posted by: Erica      Read more         Source


October 20, 2009, 10:05 PM CT

Genomes of Two Strains of E. coli Sequenced

Genomes of Two Strains of E. coli Sequenced
Electron microscopy image of several E. coli cells, including two pairs of dividing cells
An international team of scientists from the United States, Korea, and France has sequenced and analyzed the genomes of two important laboratory strains of E. coli bacteria, one used to study evolution and the other to produce proteins for basic research or practical applications. The findings will help guide future research and will also open a window to a deeper understanding of classical research that is the foundation of our understanding of basic molecular biology and genetics.

The team, which includes two scientists from the U.S. Department of Energy's (DOE) Brookhaven National Laboratory, published its results online on October 17, 2009, in three papers in the Journal of Molecular Biology.

E. coli has been linked to recent outbreaks of food-borne illnesses, but the two most important laboratory types, named K-12 and B, were isolated from non-malignant E. coli that are normal inhabitants of the human intestine. Both have been indispensable tools for biomedical research and biotechnology.

K-12 was isolated in 1922 in Palo Alto, California. Its genome sequence - the series of nucleotide bases (labeled A, T, G, and C) that make up the source code for running the machinery of the cell - has been known since 1997. The early history of B, however, was unknown until the current collaboration painstakingly analyzed historical scientific papers and personal recollections to trace it back to a strain at the Institut Pasteur, in Paris, in 1918. Adding to this historical reconstruction, the newly sequenced genomes of two different B strains allow the complete genomes of these laboratory workhorses to be compared for the first time.........

Posted by: Janet      Read more         Source

   

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