VARIATION IN COLUMBIAN MAMMOTH MOLARS, AND THE ISSUE OF MAMMOTH SPECIES IN NORTH AMERICA

During the late Pleistocene, Mammuthus meridionalis, the Southern mammoth, migrated to North America. The latest research indicates that this species later gave rise to Mammuthus columbi, the Columbian mammoth. We have studied the teeth and jaws of Mammuthus columbi from both La Brea tar pits and from Diamond Valley Lake Reservoir. There used to be multiple different species of mammoths recognized in these regions of North America, such as M. jeffersoni and M. imperator, but they have all been synonymized with Mammuthus columbi. This research was mainly conducted on mammoth molars, specifically their M3’s or more mature teeth, which were analyzed due to the fact that they have the most distinctive features necessary to differentiate them from other mammoth species. Measurements were taken on their lamellar frequency, enamel thickness, plate count, and overall tooth size as well as width. Both the La Brea and the Western Science Center specimens showed some variation between localities and other localities that contain populations of Mammuthus columbi. This data will help assess intrapopulational and interspecific variation in molars and suggest a reconsideration of the idea that all late Pleistocene North American mammoths can be lumped into a single species, Mammuthus columbi.