Dr. Paul Ellenberger will go down in history for his work on Cosesaurus, but his passion was fossil footprints. One impression he considered was this purported “hairy paw” from the Middle Triassic of France. Ellenberger (1976) named it Cynodontipus (Fig. 1). Each “toe” was about 2 inches (5 cm) in width.
Ellenberger (1976) interpreted his fossil this way (Fig. 2).
Hairy pads are not known even in modern arctic mammals, so why should we expect hairy pads in Triassic cynodonts? Especially when one can’t differentiate the pads?? There’s no match for this foot among known Triassic taxa. Perhaps there is another explanation for this enigma.
So what is it?
When we consider the “hair,” we are drawn to the therapsids as possible candidates, as Ellenberger surmised. But this fossil demonstrates way more hair than can be expected at such an early date. Even in mammals the hands and feet are the last parts to get hairy, and usually pads are plain to see, so this fossil just doesn’t fit several typical ichnite patterns.
Luckily there’s Olsen’s 2012 take on it.
Olsen 2012 wrote: In addition to its type locality in the Middle Triassic of France, Cynodontipus has been identified from the Middle Triassic of Germany, the Middle and Late Triassic of Morocco, the Late Triassic of Nova Scotia, Canada, and the Late Triassic of Connecticut, USA. This last occurrence consists of unlabeled part and counterpart slabs discovered in the Hitchcock collection at the Beneski Museum of Natural History at Amherst College. These specimens show that Cynodontipus is a vertebrate burrow that terminates at a recalcitrant subsurface bedding interface and is not a footprint. The simplest hypothesis of the trace maker of Cynodontipus is that it was a produced by burrowing procolophonids, which are know from the same deposits, are the right size, and are known to have burrowed.
Thus the lines that Ellenberger considered hairs must be tunnel scratch marks instead. Doesn’t that make more sense?
The key take away on this
Even experts can have different opinions on the same fossil. More data appears to clarify enigmas. That’s the progress of Science and that’s what makes this paleo study so fascinating. No one need vilify Ellenberger for his misinterpretation. Likewise, no one need denigrate the results published in reptileevolution.com or here at pterosaurheresies, even if and when results are shown to be in error. Errors need to be corrected, but never by blackwashing an entire output. DN and MW, I hope you’re listening. Olsen (2012) handled Ellenberger’s error very well indeed. We should all take note. Be specific and back up your corrections with evidence.
Ellenberger P 1976. Une piste avec traces de soies épaisses dans le Trias inférieur a moyen de Lodéve (Hérault, France): Cynodontipus poythrix nov. gen. nov. sp. les cynodontes in France. Géobios 9(6)769-787.
Olsen PE. 2012. Cynodontipus: A procolophonid burrow – not a hairy cynodont track (Middle-Late Triassic: Europe, Morocco, Eastern North America. Geological Society of America Abstracts with Programs, Vol. 44, No. 2, p. 92.
Olsen PE, Et-Touhami, M, Whiteside, JH, 2013 (in prep). Cynodontipus Ellenberger is a vertebrate burrow, not a hairy synapsid track. for Journal of Vertebrate Paleontology.