"What's the difference between a frog, a chicken, a mouse and a human? Not as much as you'd think, according to an analysis of the first sequenced amphibian genome." The genome of a western clawed frog has now been analyzed, and researchers say it's surprisingly similar to that of the mouse and the human. "There are megabases of sequence where gene order has changed very little since the last common ancestor" of amphibians, birds and mammals about 360 million years ago, bioinformaticist Uffe Hellsten said.