Dinosaur Train. Tiny's Fishing Friend/Butterflies. ... EGG-LAYING EARLY MAMMAL CALLED CASTOROCAUDA THAT LIVES BOTH ON LAND AND IN THE WATER AND LOVES FISH. - [squawks] CINDY, I WAS RIGHT!

Castorocauda lutrasimilis, which was unearthed in China, is a species previously unknown to science. It dates back to 164 million years ago, a time when mammals were thought to be primitive creatures ...