Monday, January 31, 2011
Frogs re-evolved lost teeth
"Frogs re-evolved 'lost' bottom teeth after more than 200 million years, according to new research. Tree-dwelling Gastrotheca guentheri are the only frogs with teeth on both their upper and lower jaw. The reappearance of these lower teeth after such a long time fuels debate about whether complex traits are lost in evolution or if they can resurface. Scientists suggest this new evidence identifies a 'loophole' in previous theories."