S11-2 Monday, Jan. 7 08:30 - 09:00 Canine Evolution in a Saber-toothed Cat (Smilodon fatalis): Static Scaling and Evidence of Natural Selection O'BRIEN, Devin; Colby College email@example.com
The canines of saber-toothed cats are a classic example of an extreme morphology, yet we know surprisingly little about how they evolved. Natural observation of these animals is impossible, and few extant species have comparable morphology. As a result, we must infer the strength and mode of selection that acted on saber-tooth canines from the fossil record, a practice that, until recently, was associated with a high degree of uncertainty. Here, I review recently established methods for inferring the strength and mode of selection from measures of static scaling. I then expand and improve upon these methods and apply them to a fossil population of saber-toothed cats (Smilodon fatalis) collected from the La Brea Tar Pits (Los Angeles, USA; Merriam, 1912). I show how static scaling relationships can be useful, reliable tools for inferring patterns of selection, especially in fossil organisms, and provide evidence that extreme canine morphology in saber-toothed cats is the product of strong natural selection.