They have also found frogs with missing eyes. One one-eyed frog had a second eye growing inside its throat.
Frogs have a small number of birth defects naturally.
We should be alarmed. Frogs are amphibians. They spend their lives both in the water and on dry land. Beginning life as eggs floating on the surface of still waters, they develop into swimming tadpoles, eventually changing completely, becoming frogs. These major changes in form occur under the control of hormones, which are chemical messengers that travel throughout the organism, turning on and off bodily processes.