"Remember Minnesota's famous deformed frogs? New studies from two groups of researchers working half a world apart have just added important insights into this tantalizing environmental puzzle -- while leaving a full explanation still out of reach.
 
It's been 14 years since a group of middle-schoolers on a field trip discovered frogs with bizarre leg malformations at a farm pond near Henderson, in the Minnesota River Valley an hour southwest of the Twin Cities. Some of the amphibians had extra hind legs that appeared as pale, shrunken imitations of normal limbs. Some were missing legs, or had legs that were partial or misshapen. ...
 
Of immediate concern was the possibility that the deformities were being caused by a water contaminant that could affect other species, including humans. By the spring of 1997, several federal agencies and a number of academic researchers were working on the problem....

Now research on frogs with missing legs in England and Oregon -- undertaken independently but arriving at identical conclusions -- has found a common cause of missing legs in frogs."

William Souder reports for MinnPost.com August 17, 2009. [2]