It is the greatest mass extinction since the dinosaurs. Population by population, species by species, amphibians are vanishing off the face of the Earth. Scientists are taking desperate measures to try to save those frogs they can, even bathing frogs in Clorox solutions and keeping them in Tupperware boxes under carefully controlled conditions to prevent the spread of a deadly fungus.

In this clip Tyrone Hayes and his students from the University of California at Berkeley are studying how agricultural chemicals, including fertilizers and pesticides, are affecting the health of frogs. Pesticides in runoff can cause an increase in stress hormones and lead to immunosuppression in frogs. In some cases Hayes has found that the presence of atrazine, a common agricultural chemical, can even cause frogs that are genetically male to develop as females and produce eggs. 51 minutes, 2009.

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