Early 4-Legged Animal Moved Like Inchworm, Study Says

One of the first four-legged creatures that walked on land had an inchwormlike gait, a new study says.

The creature, known as Ichthyostega, lived in a floodplain environment on Greenland during the Devonian period, about 360 to 410 million years ago.

About three feet (one meter) long, Ichthyostega looked like a cross between a fish and a crocodile. Its four limbs allowed it to move, for short distances, on land.