Frog Has 5 Legs But Its Easy To Explain

[matcom]

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Something doesn't seem right.

One head? Check.

Two eyes? Double check.

Limbs?

One. Two. Three. Four. Five.

Five?

The five-legged frog, captured in McHenry County and now pickled in glycerol, is featured in a new exhibit opening this weekend at the Notebaert Nature Museum.

The exhibit is called "Mysteries of the Marsh,'' but Doug Taron, curator of biology for the museum at 2430 N. Cannon, says this five-legged freak is no mystery: Its extra extremity is a consequence of overuse of fertilizers.

According to Taron, fertilizers are creating an "explosion of algae'' in wetlands and ponds. That bounty is perfect for snails, which can carry flat parasites called trematodes.

Those microscopic worms, released into the water, burrow into the tail ends of tadpoles. Once inside, they interfere with the normal development of frogs. Sometimes, the amphibians are born with one leg or a single eye.

http://www.suntimes.com/output/news/cst-nws-frog01.html