May 14, 2008, 7:39 PM CT

Restoring fish populations

You might think that stocking the Great Lakes with things like trout and salmon would be good for the herring gull. The birds often eat from the water, so it would be natural to assume that more fish would mean better dining. But a new report published in the April journal of Ecology by the Ecological Society of America says that the addition of species such as exotic salmon and trout to the area has not been good for the birds, demonstrating that fishery management actions can sometimes have very unexpected outcomes.

Craig Hebert (National Wildlife Research Center in Ottawa, Canada) and his team analyzed 25 years of data on the gulls and found that throughout the Great Lakes region, the birds were in poor health in many areas. Tests of their fatty acids showed an increase in the type of transfat that mostly comes from food produced by humans.

It seems that the birds are being forced to make a dietary shift from fish to terrestrial food, including garbage, says Hebert.

Although no one is certain why the birds are eating more garbage, evidence points to fish stocking. When exotic salmon and trout have been added to the waters, the birds seem to be out competed for their favorite prey of smaller fish, such as alewifes.

Herring gulls, which differ from the ring necked gulls that often populate American beaches and parking lots, are by no means endangered......... Posted by: Kelly      Read more         Source

May 12, 2008, 9:37 PM CT

Beyond nutrition: plants deliver

The need for a renewable and affordable source of carbon that can sustain future economic development without negatively impacting the environment is now widely recognised. It is also apparent that the increasingly high demand for fossil carbon will eventually deplete existing stocks.

The Plant Journal is pleased to present a series of invited peer-reviewed articles that describe processes that plants can or could use to convert their fixed carbon into fuels and other useful products. The articles were commissioned to provide an authoritative scientific backdrop to inform discussion in debates on finding alternative and reliable sources of carbon.

Co-edited by Christoph Benning from Michigan State University and Eran Pichersky from the University of Michigan, this special issue is freely available to download online here: http://www.blackwell-synergy.com/toc/tpj/54/4.

The 17 articles in this special issue cover topics related to the production of biofuel from plant or algal biomass. In addition, several articles highlight the usefulness of plant s for the production of pharmaceutical drugs and other high value chemicals and polymers. A flavour of the scope of articles is given below.

Smith reports on how increases in yield of starch and sugars could lead to a sustainable production of bioethanol as a liquid transport fuel......... Posted by: Erica      Read more         Source

May 12, 2008, 9:32 PM CT

Human vision inadequate for research on bird vision

The most attractive male birds attract more females and as a result are most successful in terms of reproduction. This is the starting point of a number of studies looking for factors that influence sexual selection in birds. However, is it reasonable to assume that birds see what we see? As per a research findings reported in the latest issue of American Naturalist, Uppsala scientists show that our human vision is not an adequate instrument.

The results mean that a number of studies on sexual selection may need to be re-reviewed, says Anders Odeen, research assistant at the Department of Animal Ecology at Uppsala University, who carried out this study with his colleague Olle Hstad.

The significance of birds plumage, both in terms of richness of colour and particular signals, has been shown to be a major factor in birds choice of partner. In order to assess the colours of birds, everything from binoculars to RGB image analyses are used. However, most studies are based on the hypothesis that human colour vision can be used to assess what birds see.

Its a bit like a colour blind person describing the colours of clothes its often quite accurate but sometimes it can go badly wrong.

This problem has been discussed in the research arena, but so far no study has been able to show its extent. The Uppsala scientists used a mathematical model to investigate how bird and human retina work. Using the model combined with information on differences in the colour-sensitive cones of the eye, they have been able to figure out how colour contrasts are perceived. Greater colour contrast can be translated as richness of colour or more brightly coloured......... Posted by: Kelly      Read more         Source

May 12, 2008, 8:23 PM CT

First Veterinary Corneal Implant Procedure In U.s.

Sinisa Grozdanic an assistant professor of Veterinary Clinical Sciences performed the surgery that restored sight to 7-year-old Dixie, a Mountain Cur breed owned by Brett Williams of Runnells.

"We are excited for Dixie," said Grozdanic. "She was our patient for such a long time and nothing really worked. She was gradually going down visually and we were finally able to do something to definitely improve her quality of life".

"She is my pet and my friend," said Williams. "She is the best dog I've ever had. Even when she was almost blind, she was still my best dog".

Dixie, who had gained weight due to inactivity from her blindness, has lost seven pounds since the surgery.

"She used to walk right behind me when we'd go for a walk. She couldn't see and was scared," said Williams. "Now she wants to run ahead".

Dixie's sight was restored through a two-step surgical procedure that involves cutting into the eye to take out the cloudy cornea and inserting a permanent, plastic cornea. The new cornea is sutured, or stitched, into place. The entire eye including the new, plastic cornea is then covered with tissue from the dog to help the eye heal from the surgery. Because of the tissue and the bandages, the dog cannot see after this procedure......... Posted by: Kelly      Read more         Source

May 12, 2008, 8:08 PM CT

Warming a greater danger to tropical species

Polar bears fighting for survival in the face of a rapid decline of polar ice have made the Arctic a poster child for the negative effects of climate change. But new research shows that species living in the tropics likely face the greatest peril in a warmer world.

A team led by University of Washington researchers has observed that while temperature changes will be much more extreme at high latitudes, tropical species have a far greater risk of extinction with warming of just a degree or two. That is because they are used to living within a much smaller temperature range to begin with, and once temperatures get beyond that range a number of species might not be able to cope.

"There's a strong relationship between your physiology and the climate you live in," said Joshua Tewksbury, a UW assistant professor of biology. "In the tropics a number of species appear to be living at or near their thermal optimum, a temperature that lets them thrive. But once temperature gets above the thermal optimum, fitness levels most likely decline quickly and there may not be much they can do about it."

Arctic species, by contrast, might experience temperatures ranging from subzero to a comparatively balmy 60 degrees Fahrenheit. They typically live at temperatures well below their thermal limit, and most will continue to do so even with climate change......... Posted by: Kelly      Read more         Source

May 7, 2008, 7:46 PM CT

Gardeners get advice from neighbors, friends

Where do gardeners turn when they need information about annuals, perennials, shrubs and trees" Staff at University of Minnesota Extension have published results of a survey that concludes that the majority of backyard gardeners get their planting and plant information informallymost often from friends, neighbors and local garden centers.

The survey of 1,000 Minnesota gardeners reported in the JanuaryMarch, 2008 issue of HortTechnology showed that eventhough respondents viewed the The University of Minnesota and the Minnesota Landscape Arboretum as more credible than garden centers, 78% of respondents indicated that they were most likely to turn to neighbors and friends for gardening advice.

Dr. Mary Hockenberry Meyer, Professor of Horticultural Science and Extension Horticulturist at UM Extension, explained, "We wanted to determine where gardeners got their information and if they think university information is of higher quality than information from garden centers or home centers. We observed that university information is viewed as higher quality; however, a large number of people indicated they "did not know" the quality of university information, which surprised us".

The survey also indicated that gardeners' age determined the most likely sources for information seeking. Older gardeners were less likely to use the Internet than younger gardeners. When asked "How do you learn best"", most respondents said that they had not attended a gardening class in the past year and indicated they learn best from talking with friends. Access to publications containing color photos and illustrations was also highly valued by gardeners who responded to the survey......... Posted by: Erica      Read more         Source

May 7, 2008, 7:44 PM CT

Silicon's effect on sunflowers

Vibrant, showy sunflowers are revered worldwide for their beauty and versatility. While a number of varieties of sunflower are grown specifically for their nutritional benefits, ornamental sunflowers have become standards for commercial growers and everyday gardeners. As sunflowers' popularity grows, researchers are looking for new supplements and growing methods to enhance production and quality of this celebrated annual.

Horticulturists have found ample evidence that plants depend on "essential nutrients"; naturally occurring elements that are found in normal plant tissue that are essential for the completion of the life cycle of the plant. Eventhough silicon, a predominant element in mineral soil, is not considered to be an essential nutrient for most plants, there has been limited evidence that silicon supplements affect the aesthetic qualities of ornamental flowers and crops.

Drs. Sophia Kamenidou and Todd J. Cavins, formerly of the Department of Horticulture and Landscape Architecture at Oklahoma State University, published a research study in the February, 2008 issue of HortScience in which they examine the effects of silicon supplements on sunflowers grown in greenhouse environments.

"In greenhouse production, most floricultural crops are cultivated in soilless substrates, which often supply limited amounts of plant-available silicon. The goal of this study was to determine the effects of silicon supplementation on greenhouse-produced ornamental sunflower (Helianthus annuus L. Ring of Fire).", explained Cavins. "This is one of the first studies to highlight supplemental silicon impact on horticultural traits. Most prior research on silicon has focused on disease suppression in hydroponic vegetable production. This is also one of the few examples of detrimental effects seen from high silicon concentrations"......... Posted by: Erica      Read more         Source

May 7, 2008, 6:52 PM CT

Sweet Success With Invention

An undergraduate student at Rensselaer Polytechnic Institute has learned very quickly that a spoonful of sugar really does help the medicine go down. In fact, with his invention, the sugar may actually be the medicine.

Among the most important and complex molecules in the human body, sugars control not just metabolism but also how cells communicate with one another. Graduating senior Jeffery Martin has put his basic knowledge of sugars to exceptional use by creating a lab-on-a-chip device that builds complex, highly specialized sugar molecules, mimicking one of the most important cellular structures in the human body - the Golgi Apparatus.

"Almost completely independently he has been able to come closer than scientists with decades more experience to creating an artificial Golgi," said Robert Linhardt, the Ann and John H. Broadbent Jr. '59 Senior Constellation Professor of Biocatalysis and Metabolic Engineering at Rensselaer and Martin's adviser. "He saw a problem in the drug discovery process and almost instantly devised a way to solve it."

Cells build sugars in a cellular organelle known as the Golgi Apparatus. Under a microscope, the Golgi looks similar to a stack of pancakes. The strange-looking organelle finishes the process of protein synthesis by decorating the proteins with highly specialized arrangements of sugars. The final sugar-coated molecule is then sent out into the cell to aid in cell communication and to help determine the cell's function in the body......... Posted by: Janet      Read more         Source

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, 9:09 PM CT

Ecologists tease out private lives of plants and their pollinators

The quality of pollen a plant produces is closely tied to its sexual habits, ecologists have discovered. As well as helping explain the evolution of such intimate relationships between plants and pollinators, the study one of the first of its kind and published online in the British Ecological Society's journal Functional Ecology also helps explain the recent dramatic decline in certain bumblebee species found in the shrinking areas of species-rich chalk grasslands and hay meadows across Northern Europe.

Relationships between plants and pollinators have fascinated ecologists since Darwin's day. While ecologists have long known that pollinators such as honeybees and bumblebees are often faithful to certain flowers, and have done much work on the role of nectar as a food source, very little is known about how pollen quality affects these relationships.

Working on Salisbury Plain, the largest area of unimproved chalk grassland in north west Europe, ecologists from the universities of Plymouth, Stirling and Poitiers in France collected pollen from 23 different flowering plant species, 13 of which are only pollinated by insects while the other 10 species can either pollinate themselves or be insect pollinated. They analysed the pollen for protein content and, in the second part of the study, recorded bumblebee foraging behaviour......... Posted by: Erica      Read more         Source