CNNW The Situation Room March 23, 2013
0 cincinnati zoo. at one point, there were billions of these birds. so many that they would travel in large floks that would darken the sky. commercial and recreational hunting led to extinction. now the same science that brought us dolly the cloned sheep has advanced to the point where scientists might be able to bring them back. the extinction is national geographic story. >> maybe it got frozen somehow, you can use that to create an embryo, you can implant it in a living animal, that egg will become an animal. >> don't expect t-rex with the museum of natural history. >> you have to divide i...