Earth Science Week, Fossil Day: Ruffin’s Slab
Originally posted on Research & Collections:
North Carolina has good localities for Mesozoic fossils, but the most enigmatic and, to me, most interesting ones are from the Proterozoic (once called Precambrian). The Ediacaran Period is part of the latest Proterozoic, often called the Neoproterozoic. The Cambrian is still the Cambrian, and at the base of the Cambrian is what is often called the “Cambrian Explosion.” At that point in the Earth’s history, animals developed hard parts that could be easily fossilized.
Before that? The Cambrian Explosion actually had a very long fuse. Life existed, but without the hard parts that fossilize and leave us a record. So what is found in the Proterozoic are casts and molds of soft-bodied life forms, and the tracks and trails that some of them made. (We’ll leave aside all the geochemical data regarding stratigraphy and living organisms in the Proterozoic.)