Newly Discovered Paddle Prints Show How Nothosaurs Swam

Posted on June 12, 2014

Scientists have discovered fossilized tracks that were made on an ancient seabed in southern China. Scientists from the University of Bristol and colleagues in China believe the trackways were made by nothosaurs. The researchers say the tracks "consist of slots in the mud arranged in pairs, and in long series of ten to fifty that follow straight lines and sweeping curves."

Nothosaurs lived during the Triassic period about 245 million years ago. They had four paddle like limbs. Scientists say the size and spacing of the uncovered tracks indicate they were created by the forelimbs of nothosaurs. The animal that made the tracks was moving from left to right. The tracks are the first evidence of how these creatures propelled themselves in the water.

Professor Qiyue Zhang from Chengdu Center of China Geological Survey, leader of the research, says in a statement, "We interpret the tracks as foraging trails. The nothosaur was a predator, and this was a smart way to feed. As its paddles scooped out the soft mud, they probably disturbed fishes and shrimps, which it snapped up with needle-sharp teeth."

Professor Michael Benton from the University of Bristol, a co-author of the study, says, "When I first saw the site, I couldn't believe the amazing quality of the fossils. It's quite unusual to find skeletons of marine reptiles such as the nothosaurs so close to evidence of their tracks."

A research paper, "Nothosaur foraging tracks from the Middle Triassic of southwestern China," was published here in Nature Communications.

ANIMALS