URI scientists believe birds can teach us about healthy eating


Want to know what kinds of foods prevent disease? Then watch what migratory birds eat during their stopovers on Block Island. Two University of Rhode Island scientists believe that birds choose certain berries because they offer protection against oxidative stress that occurs during long flights. Oxidative stress can lead to inflammation and a variety of diseases in birds and humans. The team's preliminary findings show that birds stopping over on Block Island favor the arrow-wood berry, which contains more anti-oxidants and pigments than the 11 other island berries studied by the researchers. Navindra Seeram, assistant professor of pharmacy and head of the Bioactive Botanical Research Laboratory at URI, and Scott McWilliams, URI professor of wildlife ecology and physiology, have teamed up to research migratory birds' eating habits and how their diets might be used to understand the role of berries rich in anti-oxidants in human health. Research has shown a diet rich in anti-oxidants can help prevent cancer and other serious illnesses. Seeram reported the findings today at the American Chemical Society's 239th national meeting in San Francisco. (Seeram will be interviewed about this on NPR's Science Friday, March 26.) ''We're suggesting that birds choose deeply colored berry fruits in part because of their anti-oxidant properties,'' Seeram said. About 11 years before Seeram arrived at URI, McWilliams began laying the foundation for the recent study. ''When I started studying birds during their migratory stopover on Block Island, I was impressed that most of the migratory birds ate berry fruits even though they usually eat insects or seeds at other times of the year,'' said McWilliams, who came to URI in 1999. ''I began studying the relationship between the nutritional qualities of fruits and how those nutrients might fuel migration.'' When Seeram arrived at URI two years ago, McWilliams saw a University story online that detailed Seeram's research interests. ''I saw the story about Navindra and in it he was talking about oxidative stress and inflammation and the effects berry fruits can have on reducing those impacts on people.'' So McWilliams, who does his research and teaches in the College of the Environment and Life Sciences, tracked down Seeram, who works in the College of Pharmacy. They developed their mutual research interests into a successful collaboration that included URI graduate student Jessica Bolser and post-doctoral researcher Liya Li, who works in Seeram's lab. Called the lynchpin between McWilliams and Seeram, Bolser spent months in the field on Block Island observing the birds' nutritional patterns and collecting batches of 12 different kinds of berries for their analysis of anti-oxidant levels. The research indicates that birds prefer to eat certain fruits that have more antioxidants and key nutrients. In return, the seeds in the berries are dispersed by the birds. ''It's the way plants ensure their survival. Birds eat the berries, digest them and defecate the seeds over wide areas,'' McWilliams said. ''Meanwhile, the birds are attracted to the berries because of their rich color, which we believe is a plant's response to the stress of constant exposure to the sun and other stresses. Berry color could be a plant's way of fighting oxidative stress. It's a partnership that benefits plant and bird.'' The Seeram-McWilliams partnership will continue. ''We've only measured a few of these anti-oxidants,'' Seeram said. ''Our next step is to determine how birds can detect these compounds.'' ''Whenever we exercise, we undergo oxidative stress, and the same is true for birds,'' McWilliams said. ''We're flying birds in wind tunnels to produce oxidative stress, and then we are going to see if anti-oxidants found in these berries alleviate that stress,'' McWilliams said. The research may benefit human health as well as bird conservation. If further research shows the direct link between bird health and diet, then the findings will play a critical role in habitat protection for migratory birds, McWilliams said. ''That's what is so great about URI,'' Seeram said. ''Because the University is small, without the usual bureaucratic walls, we can create these partnerships. This collaboration between professors in two separate colleges would not have happened so easily in other universities and produced results so quickly.''Source: Article
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Animals have personalities too…..

An individual's personality can have a big effect on their life. Some people are outgoing and gregarious while others find novel situations stressful which can be detrimental to their health and wellbeing. Increasingly, scientists are discovering that animals are no different. A new study led by Dr Kathryn Arnold, of the Environment Department at the University of York has added important experimental evidence showing that animal personalities are reflected in their oxidative stress profiles. The research is published in the Journal of Experimental Biology. Dr Arnold teamed up with graduate student Katherine Herborn, at the Institute of Biodiversity, Animal Health and Comparative Medicine at the University of Glasgow, to classify the personalities of 22 greenfinches. They tested each bird's reactions to a novel situation by adding a brightly coloured cookie-cutter to each greenfinch's food bowl, and timing how long it took for the birds to pluck up courage to approach the  food. The researchers found that the boldes birds took only a few seconds to overcome their fear while more timid birds took up to 30 minutes to approach their meal. Dr Arnold and Katherine Herborn also measured the greenfinches' motivation to explore by attaching an intriguing object to the birds' perches and timing how long it took them to land next to it. However, there was no correlation between the birds' courage and curiosity. The researchers then measured the birds' damaging reactive oxygen metabolite levels and their defences against them. Comparing the bird's blood oxidative profiles with their personalities, the team found that the most timid birds had the highest levels of damaging oxygen toxins and the weakest defences, so they suffered more oxidative stress than braver individuals. Also, the scientists found that the most curious birds (those that approached objects fastest) had better defences against oxidative damage than less curious greenfinches. Dr Arnold wants to extend the work to establish how personality traits affects birds in the wild. She says, ''Neophobic birds – those that are afraid of new things – may suffer high costs of oxidative stress and die early because they paid these physiological costs, but they might also be less likely to be eaten by a predator because they are more wary than bolder birds.'' The research also involved scientists at The Edward Grey Institute, Department of Zoology at Oxford and the WALTHAM Centre for Pet Nutrition at Melton Mowbray, Leicestershire. The research was part-funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Royal Society. Source: Article,
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How do Birds get their Color?



Birds have captivated us for time eternal, not only because of their ability to fly, but also because of the color they add to our lives. Ok, let me be clear that I’m not suggesting that ALL birds are colorful. Birds like Plain Chachalacas and Grey Catbirds hardly evoke images of stunning beauty. But a vast number of species DO exhibit dazzling displays of color. And these displays are not always what they might seem. Have you ever wondered why grackles look iridescent blue in good light and black in bad light? Or why the colorful gorgets of male hummingbirds appear and then disappear without warning? This is because color in birds is not a simple thing. But rather it is a complex concoction of some very specific recipes. There are two main ingredients that are essential in the making of color. The first is pigment and the second is keratin. And the ways in which these two fundamental ingredients are added to the color cooking pot are what produces the final colors that we see. Pigments are relatively simple color makers. There are three main pigments that give feathers their colors. The first pigment is called melanin and it produces black or dark brown coloration. Melanin is also very strong and is thus often reserved for the flight feathers. White feathers are caused by a lack of pigmentation and are much weaker than black feathers due to the lack of melanin. This might explain why many predominantly-white bird species have entirely black or black-tipped feathers in their wings. These feathers are exposed to the greatest wear
Pied Kingfisher, Ceryle rudis at Pilanesberg National Park, South Africa
and are required to be stronger than regular feathers. The second group of pigments are called carotenoids and they produce red, orange or yellow feathers. Carotenoids are produced by plants. When birds ingest either plant matter or something that has eaten a plant, they also ingest the carotenoids that produce the colors in their feathers. The pink color of flamingoes, for example, is derived
from carotenoids found in the crustaceans and algae that the birds sieve from the water. The third group of pigments are called porphyrins and these are essentially modified amino acids. Porphyrins can produce red, brown, pink and green colors. This pigment group is the rarest of the three pigment groups and is found in only a handful of bird families. The best-known example of porphyrins is the red pigment (often called turacin) that is found in many turaco species and turacoverdin, the green pigment found in
many of the same turaco species. Mixtures of pigments can also produce different and unusual color hues and shades. For example, the dull olive-green colors of certain forest birds is actually a mixture of yellow carotenoid pigments and dark-brown melanin pigments. Then we get to the second main ingredient that produces color: keratin. Keratin is the tough protein of which feathers are made. It also covers birds’ bills, feet and legs. Keratin is responsible for the iridescent coloring of many spectacular bird species. How keratin produces color is a rather complex process but, from what I’ve read on the subject, I shall attempt to simplify it as follows. Keratin produces color in two main ways: by layering and by scattering. Layering colors are produced when translucent keratin reflects short wave-lengths of colors like blues, violets, purples and greens. The other colors are absorbed by an underlying melanin (black) layer. The ways in which the keratin of the feathers are layered will dictate the color of the iridescence. Examples of layered coloring include the iridescence of glossy starlings and the speculums or wing patches of many duck species. Scattering is produced when the keratin of feathers is interspersed with tiny air pockets within the structure of the feathers themselves. These air pockets and the interspersed keratin scatter blue and green light and produce the shimmering colors of birds like kingfishers, rollers and bee-eaters.  The magnificence of some of these scattered colors is wonderfully exhibited in Adam
Guêpiers d'Europe
Riley’s post on the “Bee- eaters of Africa”. And like any really good dish, there are times when several ingredients need to be mixed  together to produce  a really good recipe. And both keratin and pigments can be combined to produce certain colors. The greens of many parrot species are caused by blue scattered light (produced by keratin) interacting with yellow carotenoids (produced by pigments in the feathers). Grey feathers are produced by the combination of scattered white light and melanin pigments. Learning a little about how color is produced in birds now presents me with an entirely new birding challenge when out in the field: figuring out the various color recipes that birds employ to dazzle! Source: Article, Images: flickr.com
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Pigeons use mental map to navigate

white dove snip
Washington, Homing pigeons fly off from anand still manage to find their way home using a mental map, a new study has revealed. Despite intensive research, it is not yet definitively clear where this unusual gift comes from. All we know is that homing pigeons and migratory birds determine their flight direction with the help of the Earth's magnetic field, the stars and the position of the sun. Research proposes two approaches to explain how homing pigeons can find their home loft when released from an unfamiliar place. The first version assumes that pigeons compare the coordinates of their current location with those of the home loft and then systematically reduce the difference between the two until they have brought the two points together. If this version is accurate, it would mean that pigeons navigate like flying robots. The second version accords the pigeons a spatial understanding and "knowledge" of their position in space relative to their home loft. This would presuppose a type of mental map in their brain and thus cognitive capabilities. Up until now, there has not been any clear evidence to support the two navigation variants proposed. For their experiments, Nicole Blaser, a doctoral student in biology at the University of Zurich and her colleagues fitted homing pigeons with miniature GPS loggers in order to monitor the birds' flight paths. Blaser concluded that pigeons can determine their location and their direction of flight relative to the target and can choose between several targets. They thus have a type of cognitive navigational map in their heads and have cognitive capabilities. The study is published in the Journal of Experimental Biology. (ANI). Source: Article, Image: flickr.com
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Climate Adaptation Difficult For Europe’s Birds

For the past 20 years, the climate in Europe has been getting warmer. Species of bird and butterfly which thrive in cool temperatures therefore need to move further north. However, they have difficulty adapting to the warmer climate quickly enough, as shown by new research published in the journal Nature Climate Change. Åke Lindström is Professor of Animal Ecology at Lund University, Sweden. Together with other European researchers he has looked at 20 years’ worth of data on birds, butterflies and summer temperatures. During this period, Europe has become warmer and set temperatures have shifted northwards by 250 km. Bird and butterfly communities have not moved at the same rate. “Both butterflies and birds respond to climate change, but not fast enough to keep up with an increasingly warm climate. We don’t know what the long-term ecological effects of this will be”, says Åke Lindström. Butterflies have adapted more quickly to the changing temperatures and have moved on average 114 km north, whereas birds have only moved 37 km. A likely reason is that butterflies have much shorter lifespans and therefore adapt more quickly to climate change. Because birds like to return to the same breeding ground as in previous years, there is also greater inertia in the bird system. “A worrying aspect of this is if birds fall out of step with butterflies, because caterpillars and insects in general represent an important source of food for many birds”, says Åke Lindström. Sweden shows the strongest trends with regard to birds; however, there is no corresponding Swedish data for butterflies. For the study, the birds have been divided into ‘cold’ and ‘warm’ species, i.e. birds that thrive in slightly cooler or warmer temperatures. For example, chaffinches and reed buntings are ‘colder’ species and blackcaps and goldfinches ‘warmer’ species. In general, the researchers have observed that ‘warm’ birds are on the increase and ‘cold’ birds are in decline. When new species are seen in an area and others disappear, it is more often ‘warm’ species that arrive and ‘cold’ species that disappear. “Over the past 50 years the main factors affecting bird and butterfly numbers and distribution have been agriculture, forestry and urbanisation. Climate change is now emerging as an increasingly important factor in the development of biodiversity”, says Åke Lindström, continuing: “For Sweden, this will probably mean more species of bird in the long run; many new species are already arriving from the continent.” Åke Lindström works among other things on the projects BECC (Biodiversity and Ecosystem Services in a Changing Climate) and CanMove (Centre for Animal Movement Research) at Lund University in Sweden. The study is a joint European project with data from 20 years and seven countries (Spain, France, the Netherlands, Sweden, the UK, Finland and the Czech Republic). The Swedish data covers birds and temperatures and has been gathered on behalf of the Swedish Environmental Protection Agency. Contacts and sources: Åke Lindström, Source: http://www.ineffableisland.com
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