Ichnology is the study of trace fossils (also termed ichnofossils). Opposed to body fossils, the physical remains of an organism, trace fossils are the fossilised interactions between an organism and the substrate/sediment and include such things as trackways, excrement, burrows, bite marks and borings. Both body fossils and trace fossils are important when studying an organism and especially so in determining palaeoecology (how an organism interacted with its immediate environment). Body fossils can only inform us of the anatomy of the dead organism and its physical constraints, from which we can infer modes of life. Trace fossils, on the other hand, record the activity of organisms in life; it can be possible to see evidence of how certain communities functioned, or how an organism interacted with its environment. However one drawback is that the producer of a trace fossil is not always known, or we can't be certain that any one organism produced a specific trace.

In the second part of this two-part episode, we speak to Prof. Anthony Martin from Emory Euniversity, USA, archosaur burrows, the feasibility of dinosaurs over-wintering on the South Pole and Paleo-Barbie.