I always like it when a new discovery comes along that makes the scientific community rethink some of its views. Here is one on prehistoric beavers
In the conventional view, the earliest mammals were small, primitive shrewlike creatures that did not begin to explore the world's varied environments until the dinosaurs died out 65 million years ago.
But scientists are reporting today that they have uncovered fossils of a swimming, fish-eating mammal that lived in China fully 164 million years ago, well before it was thought that some mammals could have spent much of their lives in water.
The extinct species appears to have been an amalgam of animals. It had a broad, scaly tail, flat like a beaver's. Its sharp teeth seemed ideal for eating fish, like an otter's. Its likely lifestyle -- burrowing in tunnels on shore and dog-paddling in water -- reminds scientists of the modern platypus.
Its skeleton suggests that it was about 20 inches long.
Sounds like something out of a Crichton novel.