I am an Australian palaeontologist living in Johannesburg, South Africa. I am one of the lucky few who were able to turn their childhood passion into a career - so now I get paid to dig up and study dinosaurs. Oh, I also have to teach, but that's ok.
Francois Durand's side-winding trace from the Clarens Formation. From Durand (2005.
Discussion about fossil side-winding traces over at Tet Zoo prompted me to get off my butt and actually put something up on this blog. Its Francois Durand's apparent side-winding trace from the Clarens Formation of South Africa. Not much has been made of this and the only two references to it that I know of are rather obscure so I'm putting it up here to let people know about it. It certainly looks like a track left by a modern sidewinding viper.
A modern side-winder
Francois made it fairly clear in his presentation of this fossil to the Geoscience Africa conferance back in 2004 that he thought it was made by an Early Jurassic viperid although he only hints at this in the two publications featuring this fossil that I know of. Such an occurence is strongly at odds with the known fossil record of snakes. Even the most primitive snakes don't show up until the Cretaceous, and advanced snakes like viperids don't start radiating until well in the Cenozoic, thus to have a Jurassic Viperid means that just about all tradtional family level clades of snakes have massive ghost lineages stretching back tens of millions of years. The fossil record can be spotty but it ain't THAT bad. My take is that sidewinding habit may have evolved sporadically from time to time in all sorts of elongate limb-reduced tetrapods when the conditions warranted it. The whole discussion started over the possible sidewinding traces from a Permian, wet muddy, if not aquatic environment that I had a hand in describing.If correctly interpreted sidewinding need not be restrited to dry loose sand, wet sloppy mud might be just as capable of supporting it. So what was elongate sidewinding tetrapod of the Clarens? We haven't a clue.
Durand, J.F. 2004. The origin of snakes. Geoscience Africa 2004. Abstract Volume, University of the Witwatersrand, Johannesburg, South Africa, pp. 187.
Durand, J.F. 2005. Major African contributions to Palaeozoic and Mesozoic vertebrate palaeontology. Journal of African Earth Sciences 43: 53-82.