September 9, 2006, 5:36 PM CT
Python Eating Pregnant Sheep
Immovable feast ... an over-full python became stuck in the middle of a Malaysian road after swallowing a pregnant sheep / Reuters
Little bloating after a big meal is an occupational hazard for pythons. But this unfortunate creature found itself unable to slink away and sleep it off.
In fact, after swallowing a pregnant sheep, it couldn't move at all.
Firemen in the Malaysian village of Kampung Jabor, about 190km east of Kuala Lumpur, easily caught it after it was spotted on a road.
Conservationists were yesterday still deciding whether to keep the 90kg snake in a zoo or release it back into the wild.
Pythons eat no more than once a week but when they open their incredible hinged jaws, anything is fair game.
This 5.5m python found its eyes were definitely bigger than its belly.........
Posted by: Kelly Permalink Source
September 7, 2006, 7:47 PM CT
Peacock The beautiful bird
The Green Peafowl breeds from Myanmar east to Java. The IUCN lists the Green Peafowl as vulnerable to extinction due to hunting and a reduction in extent and quality of habitat. The two Pavo species will hybridize in captivity although their ranges in the wild are non-overlapping.
Some taxonomists believe that the endangered Green Peafowl is actually a complex of five distinct species although they are currently treated as one species with three subspecies. The Javanese Green Peafowl, Pavo muticus javanensis is an endemic found on the island of Java. The extinct Malay or Pahang Peafowl Pavo muticus muticus was earlier thought to be introduced by humans from Java, but fossils from the Pliocene epoch rules this out. Northern Yunnan is the home of one of the most distinctive form of Green Peafowl, The Yunnan Dragonbird Pavo muticus yunnanensis. The Arakan Dragonbird Pavo muticus spicifer was once native to Northern Western Myanmar, Southern Tibet and Assam. The Indo-Chinese or Siamese Dragonbird Pavo muticus imperator was once native to South East Myanmar and Thailand. The Annametic Dragonbird Pavo muticus annamensis inhabited the broadleaf evergreen forests of Cambodia, Vietnam, Laos, and Southern Yunnan China.
The peafowl are forest birds that nest on the ground. The Pavo peafowl are terrestrial feeders but roost in trees. They are weak fliers.........
Posted by: Kelly Permalink Source
September 7, 2006, 5:02 AM CT
Reconstructing Primeval Cognition
Padana, a young female orangutan at the Leipzig Zoo, who was one of the research subjects.
How did our evolutionary ancestors make sense of their world? What strategies did they use, for example, to find food? Fossils do not preserve thoughts, so we have so far been unable to glean any insights into the cognitive structure of our ancestors. However, in a study recently published in Current Biology (September 5, 2006), scientists at the Max Planck Institute for Psycholinguistics and their colleagues at the Max Planck Institute for Evolutionary Anthropology were able to find answers to these questions using an alternative research method: comparative psychological research. In this way, they discovered that some of the strategies shaped by evolution are evidently masked very early on by the cognitive development process unique to humans.
Being able to remember and relocate particular places where there is food is an asset to any species. There are two basic strategies for remembering the location of something: either remembering the features of the item (it was a tree, a stone, etc.), or knowing the spatial placement (left, right, middle, etc.). All animal species tested so far - from goldfish, pigeons and rats though to humans - seem to employ both strategies. However, if the type of recall task is designed so that the two strategies are in opposition, then some species (e.g. fish, rats and dogs) have a preference for locational strategies, while others (e.g. toads, chickens and children) favor those which use distinctive features.........
Posted by: Kelly Permalink Source
September 6, 2006, 5:00 AM CT
fruit flies mirrors climate change
Old World fruit fly, Drosophila subobscura superimposed over chromosomes from the species.
Fast-warming climate appears to be triggering genetic changes in a species of fruit fly that is native to Europe and was introduced into North and South America about 25 years ago.
"This is a clear signal on three different continents that climate change is occurring, and that genetic change is going along with it," said Raymond Huey, a University of Washington biology professor who is co-author of a paper describing the findings, published Aug. 31 in Science Express, the online edition of the journal Science.
The research deals with an Old World fruit fly species called Drosophila subobscura, which originally ranged from the Mediterranean Sea to Scandinavia. European biologists who studied the insect's genetic makeup more than 40 years ago noted that sections of chromosomes were inverted, something like taking part of a bar code from a consumer product and flipping it backwards. The biologists observed that the frequency of particular inversions was correlated with the latitude where a given insect was found. Inversions that were common in the north were uncommon in the south, and vice versa.
The fruit flies were accidentally introduced to the Pacific Coast of Chile in the late 1970s and to the North American West Coast in the early part of 1980s, probably on cargo ships. They spread rapidly, and in North America they are now found from near Santa Barbara, Calif., to northern Vancouver Island in British Columbia.........
Posted by: Kelly Permalink Source
September 5, 2006, 5:10 AM CT
Golden Age Of Dinosaur Discovery
The golden age of dinosaur discovery is yet upon us, according to Peter Dodson at the University of Pennsylvania. In a forthcoming issue of the Proceedings of the National Academy of Sciences, Dodson revises his groundbreaking 1990 census on the diversity of discoverable dinosaurs upward by 50%, offering a brighter outlook about the number of dinosaurs waiting to be found. His findings also add evidence that dinosaur populations were stable, and not on the decline, in the time shortly before their extinction 65 million years ago.
Dodson proposes that 1,850 genera (the plural of genus, an organizational group comprised of one or more separate species) will eventually be discovered, in total. Since the dinosaur research began in earnest in the 19th century, only 527 genera have so far been found, although that number is currently changing at the rate of 10 to 20 per year.
"It's a safe bet that a child born today could expect a very fruitful career in dinosaur paleontology," said Dodson, professor of anatomy in Penn's School of Veterinary Medicine and professor in Penn's Department of Earth and Environmental Sciences. "Unfortunately, there is a finite limit to what can be discovered, so our estimates show that the child's grandchildren won't be so fortunate as new discoveries will likely decline sharply in the early 22nd century".........
Posted by: Kelly Permalink Source
September 4, 2006, 10:03 PM CT
Otters And Lead Pollution
What has otters to do with lead pollution?
Valuable evidence about the success of the lead petrol ban has been gathered from otters by a scientist at Cardiff University.
As well as providing important new information about the secretive otter species, post-mortems on otters killed by cars since 1992 gave an insight into the levels of lead pollution in the environment. The results have important implications for human health as lead can damage the central nervous system including the brain, as well as affecting the kidney and reducing growth, especially in children.
Researcher Dr Liz Chadwick in the School of Biosciences at the University said:
"We measured the level of lead in rib-bones taken from over 300 otters found dead in south-west England between 1992 and 2004 and collected by wildlife veterinary pathologist Vic Simpson.
"We compared this with levels of lead found in stream sediment by the British Geological Society and airborne emissions recorded by the National Atmospheric Emissions Inventory. While some variation correlation to geology, we found an extremely strong decline over time, reflecting declining emissions from car fuel: otter bone lead levels in 2004 were less than a quarter of those in 1992".
Dr Chadwick stresses that the research highlights the importance of long-term monitoring and archiving of samples and shows that with help from the public, valuable use can be made of undesirable events such as wildlife road traffic accidents.........
Posted by: Kelly Permalink Source
September 4, 2006, 8:29 PM CT
Chimpanzees And Culture Transmission
Transferring knowledge through a chain of generations is a behavior not exclusive to humans, as per new findings by scientists at the Yerkes National Primate Research Center of Emory University and the University of St. Andrews, Scotland. For the first time, scientists have shown chimpanzees exhibit generational learning behavior similar to that in humans. Unlike prior findings that indicated chimpanzees simply conform to the social norms of the group, this study shows behavior and traditions can be passed along a chain of individual chimpanzees. These findings, based upon behavioral data gathered at the Yerkes Field Station in Lawrenceville, Ga., will publish online in the August 28 early edition of the Proceedings of the National Academy of Sciences.
Using a research design that simulated transmission over multiple generations, scientists Victoria Horner, PhD, of the University of St. Andrews and the Yerkes Research Center, along with Yerkes researcher Frans B.M. de Waal, PhD, and St. Andrews researcher Andrew Whiten, PhD, were able to more closely examine how chimpanzees learn from each other and the potential longevity of their culture. In doing so, they confirmed that a particular behavior can be transmitted accurately along a chain of up to six chimpanzees, representing six simulated generations equaling approximately 90 years of culture in the wild. A comparative benchmark study with three-year-old human children, conducted by St. Andrews researcher Emma Flynn, PhD, revealed similar results, providing further evidence chimpanzees, like humans, are creatures of culture.........
Posted by: Kelly Permalink Source
September 3, 2006, 5:44 AM CT
The Nanocosmos of the Cell
Both figures above show the filaments in a human nerve cell; left with a common confocal microscope, right with a STED microscope
There is an amazing and mysterious nanocosmos out there largely unexplored. How viruses infect a cell, how nerve cells transport signals or how proteins work - the nanocosmos of nature remains hidden to the human eye. However, in order to still be able to perceive the seemingly invisible, we need to enlarge the object - for example, with a fluorescence microscope. Fluorescent markers are attached to proteins and other biomolecules so that researchers can observe the marker. For a long time, low resolution prevented a deeper look into the function of proteins - single proteins with their dimension of 2-20 nanometers diameter were, until now, just too small.
Researchers at the Max Planck Institute for Biophysical Chemistry in Gottingen have now achieved a resolution of up to 15nm with their STED microscope (Stimulated Emission Depletion). Their fluorescence microscope is thereby twelve times sharper than a conventional one. Already in April, the team of researchers lead by Professor Stefan Hell achieved a detail sharpness of up to 60 nanometers in cells.
Only a few years ago, physicists believed that it was impossible to resolve details that lie closer together than 200 nanometers. This limit is imposed by Abbe's Law, whereby the resolution of a light microscope cannot be more accurate than half of the wavelength of light entering the microscope.........
Posted by: Kelly Permalink Source
September 3, 2006, 5:33 AM CT
Urban Birds Are More Resistant To Stress
Image: Juvenile European blackbird.
A number of species have developed a symbiotic relationship with humans. For example, European blackbirds, European starlings and house sparrows thrive in concrete habitats around the globe. The sparrow is now so closely linked to man that its original niche is unknown, whereas the European blackbird was - as little as 200 years ago - a reclusive forest dweller. These species seem to profit, for instance, by the warmer microclimate and additional anthropogenic food supply in cities. However, they are also confronted with a number of novel and potentially stressful anthropogenic disturbances, such as the permanent presence of humans, higher densities of cats and dogs, noise and light pollution as well as traffic.
Among the physiological coping mechanisms used by vertebrates - including humans - to ensure survival under adverse environmental conditions is the acute stress response, characterised by the release of glucocorticoid steroid hormones. The acute short-term secretion of these hormones is considered beneficial in that it helps to mediate adaptive behavioural and physiological responses. In prolonged stress situations, however, chronically elevated levels of circulating glucocorticoids can impair reproductive, immune, and brain functions. Thus, wild animals would suffer from city life unless they adjusted their stress response to the conditions in a city.........
Posted by: Kelly Permalink Source
September 2, 2006, 9:43 PM CT
Consensus In Monkey Social Networks
Research on communication typically focuses on how individuals use signals to influence the behavior of receivers, thus primarily focusing on pairs of individuals. However, the role communication plays in the emergence of social structures is rarely studied. In a new paper from The American Naturalist, Santa Fe Institute scientists Jessica Flack and David Krakauer study how power structures arise from a status communication network in a monkey society. Power structure is important because it can influence the complexity of interactions among group members.
"When building a society, it is of utemost importance that signals be informative and any sources of ambiguity minimized," says Krakauer. "This requirement is reflected in the structure and function of communication networks. A goal of this research has been to study communication at a group level rather than the more traditional communication we associate with pairs".
Using information theory, the scientists show that power emerges through consensus. There is a high degree of consensus among group members that an individual is powerful if that individual has received multiple subordination signals from a number of individuals in the case of pigtailed macaque monkeys, a silent bared-teeth display. Conversely, there is little consensus if signals come from just a few individuals.........
Posted by: Kelly Permalink Source
