Even Toughest Toads Are Being Unmanned
Clues to sex-change mystery could explain amphibian decline
By Katherine Thompson,  Newser Staff
Posted Jul 13, 2008 10:40 AM CDT
Suburban areas and agricultural runoff zones may be the most dangerous homes for frogs and toads, according to studies on sex changes in amphibians.   ((c) andy emcee)
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(Newser) – The mystery of the hermaphrodite toads may be solved: Researchers have found that various chemicals used in farming are linked to sex changes in certain amphibian species, the Independent reports. In a population of cane toads, 40% of males had developed feminine coloring and ovaries, and an additional 20% had marked female characteristics. And the toads are not unique.

Male green frogs have shown the same sex changes that one study calls "the result of multiple exposure to several chemicals at various concentrations over the lifetime." This might explain why so many species have been disappearing at alarming rates. More than 120 amphibian species have gone extinct, and a third of those remaining are at risk of falling to the same fate.