A new fossil find of a mammal that lived 120 million years ago with upright forelegs as that of a dog and stretched out hind legs like a lizard's could upturn accepted history of mammalian evolution, researchers said. The unique find was made from northeast China's Liaoning province when researchers including Chen Piji from the Chinese Academy of Sciences (cas) collected two distinct bone characteristics from the fossil of a sharp-mouthed mammal.