The whale rat has evolved to become fily aquatic. So it's lost its fur is lost, its whiskers gone. Its tail has maybe become more like an eel's tail. And its arms and its legs have both evolved into flippers. In this future world, whale rats are the size of porposes,. sleek and fully at home in the water. The coast lines in spring are a playground for restless young whale rats. High above them, a bat spreads its six foot wings and soars over the waves. But this is no ordinary bat. This is a sailing bat. It's a bat that lives in the ocean and can sail on ocean air currents for very long distances