Wednesday, October 27, 2010

NEW CARNIVOROUS MAMMAL DISCOVERED IN MADAGASCAR - FIRST IN 24 YEARS

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A new species of small carnivore, known as Durrell’s vontsira (Salanoia durrelli) has been identified by researchers from the Durrell Wildlife Conservation Trust, the Natural History Museum, London, Nature Heritage, Jersey, and Conservation International (CI). The small, cat-sized, speckled brown carnivore from the marshes of the Lac Alaotra wetlands in central eastern Madagascar weighs just over half a kilogramme and belongs to a family of carnivores only known from Madagascar. It is likely to be one of the most threatened carnivores in the world. The findings are outlined in the latest issue of the taxonomic journal Systematics and Biodiversity.

The carnivore was first seen swimming in a lake by researchers from the Durrell Wildlife Conservation Trust on a field trip surveying bamboo lemurs (Hapalemur griseus alaotrensis) in 2004. After briefly examining the animal, the team suspected they had witnessed a new species and so took photographs. By examining brown-tailed vontsira (Salanoia concolor) specimens in the Natural History Museum’s collections, Museum zoologists confirmed the animal was a new species. The brown-tailed vontsira is the closest relative of the new species, which zoologists named in honour of the conservationist and writer Gerald Durrell, who died 15 years ago.

Fidimalala Bruno Ralainasolo, a conservation biologist working for Durrell Wildlife Conservation Trust who originally captured the new carnivore, commented ‘We have known for some time that a carnivore lives in the Lac Alaotra marshes, but we’ve always assumed it was a brown-tailed vontsira that is also found in the eastern rainforests. However, differences in its skull, teeth, and paws have shown that this animal is clearly a different species with adaptations to life in an aquatic environment. It is a very exciting discovery and we decided to honour our founder, the world renowned conservationist Gerald Durrell, by naming this new species after him. However, the future of the species is very uncertain because the Lac Alaotra marshes are extremely threatened by agricultural expansion, burning and invasive plants and fish. It is a highly significant site for wildlife and the resources it provides people, and Durrell Wildlife Conservation Trust is working closely with local communities to ensure its sustainable use and to conserve Durrell’s vontsira and other important species.’

Paula Jenkins, Natural History Museum zoologist said, ‘We know very little about the small mongoose-like vontsiras because they are poorly known and rarely seen or studied in the field. This research is a fantastic example of the importance and relevance that Museum collections have for contemporary scientific research. Though people may know that museums such as the Natural History Museum hold reference collections, few people are aware how critical these collections are to our understanding of the world today.’

Stephan M Funk of Nature Heritage, formerly at Durrell Wildlife Conservation Trust and co-author of the paper, said ‘Population genetics and evolution of the Durrell’s vontsira and related species remain badly understood, highlighting the importance of future research. More important, however, is the protection of the wetlands around Lac Alaotra, which remain highly threatened.’

The habitat of Durrell’s vontsira has been suffering from a number of threats over the past decades, from introduced fish to silting and pollution from fertiliser and pesticides. While the conservation status of the new species remains to be formally evaluated, it is likely to be threatened as a result of small population size, restricted distribution and the impact of habitat degradation.

Remarkably, Lac Alaotra hit the headlines only a few months ago when the extinction of the Alaotra grebe (Tachybaptus rufolavatus) was announced. Now a new species has been described from the very area where the last Alaotra grebe was seen.

Frank Hawkins of Conservation International, co-author of the paper describing the species, said ‘This species is probably the carnivore with one of the smallest ranges in the world, and likely to be one of the most threatened. The Lac Alaotra wetlands are under considerable pressure, and only urgent conservation work to make this species a flagship for conservation will prevent its extinction.’

(Photo: © Durrell Wildlife Conservation Trust)

Conservation International


TSUNAMI RISK HIGHER IN LOS ANGELES, OTHER MAJOR CITIES

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Geologists studying the Jan. 12 Haiti earthquake say the risk of destructive tsunamis is higher than expected in places such as Kingston, Istanbul and Los Angeles.

Like Haiti's capital, these cities all lie near the coast and near an active geologic feature called a strike-slip fault where two tectonic plates slide past each other like two hands rubbing against each other.

Until now, geologists did not consider the tsunami risk to be very high in these places because when these faults rupture, they usually do not vertically displace the seafloor much, which is how most tsunamis are generated. This latest research suggests even a moderate earthquake on a strike-slip fault can generate tsunamis through submarine landslides, raising the overall tsunami risk in these places.

"The scary part about that is you do not need a large earthquake to trigger a large tsunami," said Matt Hornbach, research associate at The University of Texas at Austin's Institute for Geophysics and lead author on a paper describing the research in the Oct. 10 online edition of the journal Nature Geoscience.

"Organizations that issue tsunami warnings usually look for large earthquakes on thrust faults," said Hornbach. "Now we see you don't necessarily need those things. A moderate earthquake on a strike-slip fault can still be cause for alarm."

Within minutes after the magnitude 7 Haiti earthquake, a series of tsunami waves, some as high as 9 feet (3 meters), crashed into parts of the shoreline. A few weeks later, a team of scientists from the U.S. and Haiti conducted geological field surveys of sites on and offshore near the quake's epicenter.

The scientists determined the tsunamis were generated primarily by weak sediment at the shore that collapsed and slid along the seafloor, displacing the overlying water. Combined with newly discovered evidence of historic tsunamis, the survey revealed a third of all tsunamis in the area are generated in this way. Geologists had previously estimated only about 3 percent of tsunamis globally are generated through submarine landslides.

"We found that tsunamis around Haiti are about 10 times more likely to be generated in this way than we would have expected," said Hornbach.

In addition to Hornbach, team members from The University of Texas at Austin include: Paul Mann, Fred Taylor, Cliff Frohlich, Sean Gulick and Marcy Davis. The team also includes researchers from Queens College, City University of New York; U.S. Geological Survey, University of Missouri; Lamont-Doherty Earth Observatory of Columbia University; University of California, Santa Barbara; Bureau of Mines and Energy (Haiti); and Universite d'Etat de Haiti.

The researchers gathered data on faults beneath the seafloor and land, vertical movement of the land, bathymetry (underwater topography) of the seafloor and evidence of tsunami waves. They worked on foot, on a small inflatable boat and on the 165-foot research vessel Endeavor.

This research was funded by a Rapid Response grant from the National Science Foundation and The University of Texas at Austin's Jackson School of Geosciences.

With additional funding from The Society for Geophysics' Geoscientists Without Borders program, Hornbach and others are now conducting a new research project in nearby Jamaica to assess the tsunami threat there.

"The geology of Kingston, Jamaica is nearly identical to Port-au-Prince, Haiti," said Hornbach. "It's primed and ready to go and they need to prepare for it. The good news is, they have a leg up because they're aware of the problem."

The University of Texas at Austin

SMALLER AND CHEAPER BUT 300 TIMES MORE INTENSE

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More brilliant X-rays, more cost-effective methods for developing new energy sources and advanced manufacturing processes are just some of the benefits which may come from a novel technology, proven at the theoretical level by a consortium of British and European laser scientists.

The research, led by scientists at STFC's Central Laser Facility (CLF), is published in Nature Physics (October 10 2010).

A team of scientists from the Instituto Superior Tecnico in Lisbon, Imperial College London, and the Universities of St Andrews, Lancaster and Strathclyde as well as STFC’s Central Laser Facility staff have demonstrated the feasibility of a groundbreaking method called Raman amplification which can take long laser pulses and compress them to 1000 times shorter, but with intensities 300 times greater. This means that current very expensive and complex laser set-ups could eventually be replaced with smaller and more cost-effective systems. This would make many technologies, including methods used to develop x-rays which rely on lasers, far more accessible and easier to mass-produce. This latest development is another step in laser scientists’ quest to develop ever more powerful lasers, increasingly demanded by new technologies since the invention of the laser 50 years ago.

The technique has been examined over a two year period, using some of the world’s most powerful supercomputers, to test every possible aspect of the theory. "In the past, studies have been carried out to test the theory, but only using simplified models which do not include all of the relevant phenomena. Our new model has shown that, in most cases, the amplified laser beam breaks up into ‘spikes’, making it difficult to focus the beam to a small spot" said Dr Raoul Trines from STFC’s Central Laser Facility. "But for a few special cases, the amplified laser pulse is of excellent quality, enabling exceptionally tight focusing of the beam".

Professor John Collier, Director, STFC’s Central Laser Facility said; "This year’s celebration of 50 years of the laser* is a poignant reminder that we need to start thinking about the next generation of laser technology. We have come to rely on lasers so much in our daily lives, for everything from high speed internet connections to medical techniques, that we can’t afford to pause even for a moment in developing laser techniques further, because these new techniques take years to develop and test".

The next step is to apply the theoretical study on an actual high power laser and fine tune the method through rigorous experimental testing.

(Photo: STFC)

Science and Technology Facilities Council

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