Fossil poop shows fishy lunches from 200 million years ago

A new study of coprolites, fossil poop, shows the detail of food webs in the ancient shallow seas around Bristol in south-west England. One hungry fish ate part of the head of another fish before snipping off the tail of a passing reptile. Marie Cueille, a visiting student at the University of Bristol's School of Earth Sciences , was working on a collection of hundreds of fish poops from the Rhaetian bone bed near Chipping Sodbury in South Gloucestershire, dated at 205 million years ago. She applied new scanning technology to look inside these coprolites and found an amazing array of food remains. Marie said: "The ancient fishes and sharks of the Rhaetian seas were nearly all carnivores. Their coprolites contain scales, teeth, and bones, and these tell us who was eating whom. In fact, all the fish seem to have been snapping at each other, although the general rule of the sea probably applied: if it's smaller than you, eat it.' The CT scans of one tiny coprolite, measuring only a centimetre or so in length, contained only three bones, one a highly tuberculated skull bone of another fish, and two vertebrae from the tail of a small marine reptile called Pachystropheus .