A newly investigated 290 million year old fossil may be an evolutionary missing link in the amphibian family tree. The fossil was collected in Texas by a palaeontologist with the Smithsonian Institution in the mid-1990s. The fossil eventually ended up at the National Museum of Natural History in Washington, D.C., where it was re-discovered and investigated in 2004.

The new analysis of the fossil has been carried out by Jason Anderson, a comparative biologist at the University of Calgary, Canada. According to Anderson, the fossil has an overall amphibian look but with interesting archaic features. The animal resembles a salamander, but the tail is stubby and the ears are similar to the ears of a frog.

“So it’s kind of a frogamander, if you will,” Anderson sais to National Geographic News.

The fossilized species has been given the name Gerobatrachus hottoni. Until recently, scientists believed that frogs, salamanders and the wormlike caecilians all hailed from a common ancestor. Gerobatrachus hottoni suggests that frogs and salamanders are much more closely related to each other than to the caecilians.

Read more in Anne Casselman’s article for National Geographic News.

http://news.nationalgeographic.com/news/2008/05/080521-frog-fossil.html

The study of the fossil appears in this week’s (May 21st 2008) issue of the journal Nature.