The growing number of deformed frogs in recent years is caused at least partly by runoff from farming and ranching, new research indicates.

Nitrogen and phosphorous in the runoff fuel a cycle that results in a parasitic infection of tadpoles, resulting in loss of legs, extra legs or other deformities.

[Read](http://www.msnbc.msn.com/id/20960546/ “Read the Story”) (AP via MSNBC)