Fish trails

The Green River formation is famous for its fossil fish, which lived some 50 million years ago in what is now known as Fossil Lake. The site, now part of Fossil Butte National Monument in Wyoming, has yielded a rich and diverse group of Eocene fish, including Notegoneus osculus. That's him at left. Now, Emory paleontologist Tony Martin has interpreted trace fossils in the ancient lake bed to see into the past.

Martin's specialty is ichnology, that branch of geology/paleontology that deals with the traces left by organisms. While neoichnologists might interpret tracks or burrows to understand behavior of living organisms, paleoichnologists do them one better. They examine the fossilized evidence of past behavior and use it to add to our understanding of the biology of long-dead species.

Martin and his co-workers employed high-resolution digital images and mathematical analyses to determine that the traces left on the deep bottom of Fossil Lake were likely produced by an 18 inch N. osculus as is used the fins on the posterior part of its body to wriggle across the bottom and employ its subterminal mouth to feed on benthic organisms.

Martin actually visited Small Southern a couple of years ago. One of my colleagues has collaborated with him on many projects, and was able to persuade him to present a seminar for our students. As good a guy as he is a scientist.