Hippo zoopraxiscope

Hippos glide gracefully along a river bed by using their feet as punts, the first detailed analysis of their underwater locomotion shows. Spending relatively long periods "in flight" between punts, their movements resemble those of astronauts in microgravity, or of students boating on rivers in Oxford and Cambridge.

-- a man called Fish does for hippos what Muybridge did for horses.