March 3, 2010


Pesticide Turns Male Frogs into Females

A commonly used pesticide known as atrazine can turn male frogs into females that are successfully able to reproduce, a new study finds.

While previous work has shown atrazine can cause sexual abnormalities in frogs, such as hermaphroditism (having both male and female sex organs), this study is the first to find that atrazine’s effects are long-lasting and can influence reproduction in amphibians.

The results suggest that atrazine, which is a weed killer used primarily on corn crops, could have potentially harmful effects on populations of amphibians, animals that are already experiencing a global decline, said study author Tyrone B. Hayes of the University of California, Berkeley. Atrazine is banned in Europe.

LiveScience -
01 March 2010
R Rettner Photo Credit: T Hayes/UC Berkeley

Tests on carcasses confirm anthrax

Tests conducted on carcasses of wild boars found on the premises of the Kerala Police Academy here have confirmed anthrax.

Carcasses of seven wild boars, an eagle and a toddy cat were found on the campus of the academy at Ramavarmapuram, a part of which has thick vegetation.

. . . District Medical Officer V. Divakaran said that tests conducted at the Kerala Agricultural University’s College of Veterinary and Animal Sciences on carcasses revealed the animals had anthrax.

The Hindu -
26 February 2010
Location: Thrissur, Kerala, India - Map It

Mosquitoes -- Not Birds -- May Have Carried West Nile Virus Across U.S.

. . . "In the past, people assumed that birds played the primary role in the spread of West Nile.

"However, the rapid spread of West Nile did not follow a leap-frog pattern or move north to south along migratory bird routes like we would expect," said senior author Jason L. Rasgon, PhD, assistant professor with Bloomberg School's Malaria Research Institute and the W. Harry Feinstone Department of Molecular Microbiology and Immunology.

"When you see such rapid movement, one of the main questions we ask is: 'What are the factors that mediated this jump?' Our study shows mosquitoes are a likely candidate."

Johns Hopkins Bloomberg School of Public Health -
02 March 2010
Photo courtesy of JHSPH

Photo courtesy of Reuters/U.S. Forest Service

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