Transparency is a trait shared by all living glass frogs. In some species though, such as the Condor Glass Frog (Centrolene condor), the ventral peritoneum is white anteriorly, obscuring the heart and liver. Photo by Alejandro Arteaga.
Frozen Frogs In Alaska - During the cold winters, the Alaskan Wood Frog becomes a frog-shaped block of ice. It stops breathing, and its heart stops beating. When Spring arrives the frog thaws and returns to normal going along its merry way.