'Extinct' frog hops back into northern Israel

In this photo made available by the Israel Nature and Parks Authority Thursday, Nov. 17, 2011, a Hula Painted Frog, a species believed to be extinct is seen in a nature reserve in northern Israel. Omri Gal of Israel's Nature and Parks Authority said Thursday that the Hula Painted Frog was seen for the first time in 50 years this week. In the 1940s, a specimen ate a second frog, leading to speculation the species is cannabilistic.(AP Photo/Dror Galili)

A frog species believed to be extinct has hopped back into sight in northern Israel.
Omri Gal of Israel's Nature and Parks Authority said Thursday the Hula Painted Frog was seen for the first time in 50 years this week. He said it was declared extinct.
Gal said, "It's an amazing find, now we have a second chance to preserve the species."

A Hula painted frog is seen at a protective facility in the Hula Valley Nature Reserve in northern Israel November 17, 2011.  REUTERS/Nir Elias

The frog is native to the Hula Valley, a swamp drained in the 1950s to stop malaria.
Aquatic ecologist Dana Milstein says the frog was rare even before, and little is known about it. In the 1940s, a specimen ate a second frog, leading to speculation the species is cannibalistic.
She credited rehydration of the area for the frog sighting and said more are likely in the reserve.
© The Associated Press, 2011

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Weird Science/Tree Frogs Chill out to Collect Precious Water

Research published in the October issue of The American Naturalist shows that Australian green tree frogs survive the dry season with the help of the same phenomenon that fogs up eyeglasses in the winter.

According to researchers from Charles Darwin University in Australia, tree frogs often plop themselves down outside on cool nights during the dry season in tropical Australia. When they return to their dens, condensation forms on their cold skin -- just like it does on a pair of glasses when we come in from the cold. The researchers found that frogs absorb this moisture through their skin, which helps to keep them hydrated during periods of little or no rain.

Before this study, the frogs' dry-season excursions were a bit mysterious.

"Every once in a while, we would find frogs sitting on a stick under the open sky, on nights when it was so cold they could barely move," said Dr. Chris Tracy, who led the research. "It was a real puzzle."

Tracy and his colleagues thought this behavior might enable the frogs collect condensation, but the hypothesis had never been tested.

The researchers designed a series of experiments using real frog dens in eucalyptus trees and artificial ones made from PVC pipe. They wanted to see if the frogs could collect enough moisture through condensation to compensate for what they lost being in the cold. They found that a cold night out cost a frog as much as .07 grams of water. However, a frog could gain nearly .4 grams, or nearly 1 percent of its total body weight, in water upon returning to the warm den.

The researchers also tested how well a frog's skin could absorb water, and found that as much as 60 percent of each water drop could be absorbed.

The results show that frogs can use condensation to hydrate themselves. And in a place as arid as the Australian savannahs during the dry season, where there is essentially no rain from June through August, every little bit counts.

"When there's no water available, even a small amount can mean the difference between surviving the dry season or not," Tracy said.

Tree frogs often plop themselves down outside on cool nights during the dry season in tropical Australia. When they return to their dens, condensation forms on their cold skin -- just like it does on a pair of glasses when we come in from the cold.

(story credit: Science Daily)

(photo Credit: © Patryk Kosmider / Fotolia)

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