Something bit this bone, again and again. About two hundred and eighty million years ago.
It belonged to a young Diadectes, a plant-eater. Young, but already about as heavy as three or four grown men.
A flood carried at least three of them, dead, into a pond in what is now Texas. Then the pond dried, and they lay in the open.
Their bones carry five kinds of marks. Four are tooth marks. Scores, pits, furrows and punctures. The fifth kind is tiny holes, probably bored by insect grubs.
Most of the bites sit on the gristly joint ends. Something stripped the meat, and gnawed the joints.
The obvious suspect is Dimetrodon, the famous sailback of these Texas rocks. But none has turned up at this site.
Varanops was found here. A slim meat-eater, no heavier than a big dog. It is the prime suspect. Its teeth fit most of the bites.
Did it catch these animals alive, or find them dead? The bones cannot say. They lay in the open too long. Most of the eating probably came after death.
Either way, the researchers say, it is the oldest direct evidence yet of big land predators eating big plant-eaters. Who ate whom, written on the bone, bite by bite.
