September 20, 2006, 8:20 PM CT

Mystery Disease Killing Lions in India

Zookeepers are mournfully watching the results of the program, which began in the late 1980s at the Chhatbir Zoo and was ended in 2002 after a number of of the nearly 80 crossbred lions were struck by a mysterious disease associated with inbreeding and a weakened gene pool, said Kuldip Kumar, Punjab state's conservator of forests and wildlife.

Wildlife officials had originally hoped the hybrid cats could be introduced into the wild in an effort to bolster India's endangered wild lion population.

When the program ended, all of the male lions were given vasectomies to prevent further breeding, Kumar said.

Indian wildlife laws prohibit killing the animals.

It will take about six years for the remaining 22 crossbred lions to die of natural causes, Kumar said.........

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September 19, 2006, 9:19 PM CT

Accelerated Evolution In The Island

The notion of islands as natural test beds of evolution is nearly as old as the theory itself. The restricted scale, isolation, and sharp boundaries of islands create unique selective pressures, often to dramatic effect. Following what's known as the "island rule," small animals evolve into outsize versions of their continental counterparts while large animals shrink.

Giant tortoises and iguanas still inhabit the Galápagos and a few other remote islands today, but only fossils remain of the dwarf hippopotami, elephants, and deer that once lived on islands in Indonesia, the Mediterranean, and the Pacific Ocean. The fossil record suggests that these size changes occur rapidly after species become isolated on islands, but this long standing assumption has never been empirically examined in a systematic manner. Now, in a new study published in PLoS Biology, Virginie Millien confirms that island species undergo accelerated evolutionary changes over relatively short time frames, between decades and several thousand years.

Millien collected data from text, figures, and tables in an extensive survey of the published literature. From these datasets, she calculated a total of 826 evolutionary rates for 170 populations representing 88 species. Rates of evolutionary change, she found, decreased over time for both island and mainland species, with a slower rate of decrease for island species. The differences in evolutionary rates between island and mainland pairs also decreased over time, becoming statistically insignificant for intervals over 45,000 years. Overall, island species evolved faster than mainland species--a phenomenon that was most pronounced for intervals between 21 years through 20,000 years.........

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September 18, 2006, 10:31 PM CT

Bird Moms Manipulate Birth Order To Protect Sons

Protecting her kids from peril is the job of every good mom.

When marauding mites turn up in a house finch's nest, she shelters her sons from the blood-suckers by laying male eggs later than those containing their sturdier sisters, as per new research.

Making sure the vulnerable baby boys are exposed to mites for a shorter period allows both the sons and the daughters to survive long enough to leave the nest.

"Sons are more sensitive to the mites than daughters," said Alexander V. Badyaev of The University of Arizona in Tucson. "Mothers minimize sons' exposure to mites by laying male eggs later than female eggs. As a result, the males are in the nest fewer days."

Even so, the male chicks that grow up during mite season end up just as big as ones from the mite-free time of the year.

It's all mom's doing, Badyaev said.

Once breeding female finches are exposed to mites, their bodies make hormonal changes that affect the order of egg laying and accelerates the development of their sons while they're still in the egg.

"We've found a mechanism by which duration of growth can be adjusted to a changing risk of mortality," said Badyaev, a UA assistant professor of ecology and evolutionary biology. He added that this is the first documentation that maternal manipulation of both ovulation and growth influences the duration of development in birds.........

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September 18, 2006, 10:25 PM CT

Massive Protected Areas For Animals

The Minister of Forestry Economy of the Republic of Congo announced recently plans to create two new protected areas that together could be larger than Yellowstone National Park, spanning nearly one million hectares (3,800 square miles). Instead of bison and elk, these new protected areas contain elephants, chimpanzees, hippos, crocodiles, and some of the highest densities of gorillas on earth. The announcement was made by Minister Henri Djombo and officials from the Bronx Zoo-based Wildlife Conservation Society (WCS) at the United Nations.

"We are delighted that the Republic of Congo continues to take a leadership role in safeguarding its world-class wildlife and wildlands for generations to come," said Dr. John Robinson, WCS executive vice president for conservation and science. "This is an extraordinary achievement for the entire Congo basin region".

"The Republic of Congo depends on forest resource use for economic development, but it is also deeply committed to biodiversity conservation and sustainable forest management. It has already set aside an estimated 11 percent of the country's surface area as protected areas, 90 percent of which is tropical forest. Establishing these new protected areas reinforces the protected area network portfolio and affirms this commitment," said Henri Djombo, Congo's Minister of Forestry Economy.........

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September 18, 2006, 6:36 PM CT

Fish That Can Walk

There are many more species to be discovered under the sea. Researchers examining the undersea fauna off Indonesia's Papua province said Monday they had discovered dozens of new species, including a shark that walks on its fins and a shrimp that looks like a praying mantis.

"It's one of the most stunningly beautiful landscapes and seascapes on the planet," said Mark Erdmann, a senior adviser of Conservation International who led two surveys to the area earlier this year.

"Above and below water, it's simply mind blowing," he said.........

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September 17, 2006, 10:30 PM CT

Demoting Southeast Asia's Forest Ox

It was one of the most famous discoveries of the 20th century. Shrouded in mystery since its recognition as a new species in 1937, the kouprey -- an ox with dramatic, curving horns -- has been an icon of Southeast Asian conservation. Feared extinct, it's been the object of perilous expeditions to the region's jungles by adventurers, researchers and journalists.

Now, in a paper published by the Journal of Zoology (London), Northwestern University biologists and a Cambodian conservationist present compelling genetic evidence that the kouprey may never have existed as a wild, natural species.

The scientists compared a published DNA sequence from the kouprey with sequences obtained from a true Cambodian wild ox, the banteng. The scientists had predicted, based on a study of kouprey anatomy, that the kouprey was a hybrid form and would show mitochondrial DNA similar to that of the banteng. The prediction was confirmed by their analysis.

The kouprey, which is now the national animal of Cambodia, may have originated as a domestic hybrid, between banteng and zebu cattle, that later became wild. ("Kouprey" means "forest ox" in the Khmer language.).

"The kouprey has acquired a rather romantic, exotic reputation," said Gary J. Galbreath, senior author of the paper and associate director of Northwestern's Program in Biological Sciences. "Some people would understandably be sad to see it dethroned as a species."........

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September 14, 2006, 7:32 PM CT

Rodent's Bizarre Traits Deepen Mystery Of Genetics

A shadowy rodent has potential to shed light on human genetics and the mysteries of evolution.

Purdue University research has shown that the vole, a mouselike rodent, is not only the fastest evolving mammal, but also harbors many puzzling genetic traits that challenge current scientific understanding.

"Nobody has posters of voles on their wall," said J. Andrew DeWoody, associate professor of genetics in the Department of Forestry and Natural Resources, whose study appears this month in the journal Genetica. "But when it comes down to it, voles deserve more attention".

Small rodents often confused for mice, except with shorter tails and beady eyes, voles live throughout the Northern Hemisphere and are often considered agricultural pests because they eat vegetation. Nevertheless, voles are an "evolutionary enigma" with a number of bizarre traits, DeWoody said. Understanding the basis for these traits could lead to better understanding of the same phenomena in human genetics and inherited disorders, and could have implications for gene treatment, he said.

The study focuses on 60 species within the vole genus Microtus, which has evolved in the last 500,000 to 2 million years. This means voles are evolving 60-100 times faster than the average vertebrate in terms of creating different species. Within the genus (the level of taxonomic classification above species), the number of chromosomes in voles ranges from 17-64. DeWoody said that this is an unusual finding, since species within a single genus often have the same chromosome number.........

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September 14, 2006, 4:31 AM CT

Warming might affect polar bear population

Some travel agencies touting Arctic tours have been revving up their recent promotions to tourists about the increased likelihood they will spot polar bears in this region where several populations of polar bears live. According to scientists from NASA and the Canadian Wildlife Service, these increased Arctic polar bear sightings are probably related to retreating sea ice triggered by climate warming and not due to population increases as some may believe.

The new research suggests that progressively earlier breakup of the Arctic sea ice, stimulated by climate warming, shortens the spring hunting season for female polar bears in Western Hudson Bay and is likely responsible for the continuing fall in the average weight of these bears. As females become lighter, their ability to reproduce and the survival of their young decline. Also, as the bears become thinner, they are more likely to push into human settlements for food, giving the impression that the population is increasing. The study will be published this week in the recent issue of the Journal Arctic.

Claire Parkinson, a scientist at NASA's Goddard Space Flight Center, Greenbelt, Md., and Ian Stirling, a senior scientist with the Canadian Wildlife Service, Edmonton, Alberta, used NASA satellite observations captured from 1979 to 2004 to show the reduction in sea ice cover in several specific areas where there are known polar bear populations. In most of the areas studied, they found that ice break-up in these areas has been occurring progressively earlier.........

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September 13, 2006, 9:14 PM CT

Expedition to polar research

What better way to engage students in science than to apply lessons learned from fieldwork? This is the philosophy of Alaska teachers participating in the Arctic Expedition for K-12 Teachers, a program organized by the International Arctic Research Center (IARC) at the University of Alaska Fairbanks and a handful of international agencies.

For 33 days teachers from Alaska, Canada, France, Germany, Russia, Sweden and England will take atmospheric measurements, collect ice cores, install ice mass balance sensors and more, all under the guidance of an international team of polar researchers. Teachers and scientists will work together to collect data. Their work is based on the Kapitan Dranitsyn, an icebreaker currently cruising through the Arctic Ocean.

Todd Hindman, a teacher from Nome City School District, said This will give my students an opportunity to learn about the environment they live in, which will engage them in a meaningful way both inside and outside of the traditional classroom walls.

The experience will enhance my teaching by increasing my understanding of ocean systems, said Katie Turner, a science teacher at West Anchorage High School. It will give me real world experience and knowledge to share with my students.

The expedition advances scientists work in the fields of meteorology, biology, chemistry and oceanography. Five IARC scientists are aboard the Kapitan Dranitsyn, too, as part of the Nansen and Amundsen Basins Observational System (NABOS). Their aim is to better understand a flow of anomalous warm Atlantic water entering the Arctic Ocean. Preliminary data suggests this infusion of water from the Atlantic is increasing the temperature of the Arctic waters.........

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September 11, 2006, 8:15 PM CT

Sheep Need Virus for Reproduction

A team of researchers from Texas A&M University and The University of Glasgow Veterinary School in Scotland has discovered that naturally occurring endogenous retroviruses are mandatory for pregnancy in sheep.

In particular, a class of endogenous retroviruses, known as endogenous retroviruses correlation to Jaagsiekte sheep retrovirus or enJSRVs, are critical during the early phase of pregnancy when the placenta begins to develop.

Retroviruses, such as human immunodeficiency virus or HIV, are one class of viruses. They are best known for their ability to cause diseases, said Dr. Thomas Spencer, a reproductive biologist with the Texas Agricultural Experiment Station and Texas A&M University.

Findings published Sept. 11 in the Proceedings of the National Academy of Sciences demonstrate enJSRVs are essential for the development of the placenta in sheep.

Retroviruses are unique for their ability to permanently insert their genetic material into the DNA of host cells, he said. During evolution of mammals, some retroviruses infected the germline (cells of the ovary and testis that have genetic material that are passed to their offspring) of the host, which is then inherited by their children. These retroviruses, known as endogenous retroviruses, are present in the genome of all mammals, including humans. Consequently, endogenous retroviruses can be considered remnants of ancient retroviral infections, Spencer said.........

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