Tracking the oldest cats
It has been a few hectic weeks with many interesting things going on but no time at all for blog-writing. Late last month I travelled to Vitoria (Alava, Basque Country) to give a talk about a truly unique fossil site: the Miocene fossil tracksite of Salinas de Añana. Preparing that talk helped me refresh my mind about a site that had kept us busy for years with the task of deciphering an incredibly rich treasure of paleobiological information.
The Salinas site preserves uniquely long trackways of 3 species of carnivores of early Miocene age (a lynx-sized felid, a domestic-cat sized felid or primitive hyaenid, and a mongoose), plus a couple of artiodactyles and two birds. But as you can see in the images below, not only the trackways are exceptionally long, but the quality of the preservation is simply miraculous. The shape and texture of the foot pads are recorded as finely as if the cat had freshly walked on wet cement in front of your eyes. Such unusual preservation revealed to us that some cats of the lower Miocene were almost, but not not quite as fully digitgrade as our modern felines; that they “changed gears” from walk to trot with increased speed in a thoroughly cat-like manner, and that they travelled as family units of mother and young at least until the cubs were fully adult sized. We also found that the foot morphology and locomotion of early Miocene mongooses were fully modern, which was a welcome piece of information since the post-craneal skeleton of those creatures was and remains virtually unknown.
The amount of information contained in the bare 70 square metres of exposed sediment was so huge it took us years to publish our interpretation of the carnivore trackways . But the delicate nature of the sediments made them quite fragile too. After the second field campaign in 1993 the site was re-buried, and has remained so since then. If we should open the site without proper protection it would quickly erode away under the weather, so until the regional authorities provide some sort of legal protection and funding for preservation, the trackways will remain hidden from view.
It is ironic that, after 18 million years under rock, the site has spent 18 years under earth. Not only is this a lost opportunity for refined research and for paleontological tourism at the locality, but also it is to be expected that, if we excavate a larger area, more ichnological surprises will appear.
By the way here is the reference to our Salinas publication: Anton, M., G. López y R. Santamaría, 2004. Carnivore trackways from the Miocene site of Salinas de Añana (Álava, Spain)Ichnos11: 371-384 .