All tetrapods descended from a common ancestor that just happened to have limbs with five digits. And over the eons of evolution following that, natural selection worked with variations on ...

The common ancestor of all living tetrapods must have somehow evolved to have five fingers and passed that pattern down to its descendants. A common ancestor explains how mammals got five fingers ...

This video abstract depicts how by studying neural circuits in skates, a fish species whose common ancestor with tetrapods existed ~420 million years ago, Dasen and colleagues provide insights ...