Fossils challenge assumptions on how animals adapted to land (opens in new tab)

But new research out Thursday in the journal Science challenges that conventional assumption. It presents analysis of rare fossils which scientists say fill knowledge gaps on the development of the creatures that gave rise to the first land-dwelling vertebrates. The research centers on specimens excavated from the Mazon Creek fossil beds in northern Illinois, southwest of Chicago. The world-renowned site features iron carbonate concretions that formed some 309 million years ago, fossilizing w...