Transitional fossils offer tangible evidence of evolution. Examples include feathered dinosaurs, tetrapod-like fish, and the pterosaur I described in an earlier post. These relics, some of which were predicted before they were found, testify to dramatic changes in lifestyle, body form, and behavior. Lately, a terrestrial fish has me thinking about living species that, like these fossils, appear to be in the midst of evolutionary transitions. Yes, you read that right: a terrestrial fish.