Funds from this award will be used to develop new tooth and skeletal indicators of mammal health that can be applied to fossil populations of mammals. To do so, the association between overall health and the animal's anatomy will be documented using jaws collected over the past fifty years from a well-studied predator-prey pair, Isle Royale National Park gray wolf and moose, that are known to have suffered multiple food shortages. Nutritional stress in predator and prey will be assessed based on quantifiable microscopic and macroscopic features of their teeth and skeletons. The ability to see these indicators in fossils will then be tested on extinct bison from the Rancho La Brea tar seep deposits of California that are between 50,000 to 11,000 years old. Assuming the method works, it can be used to infer relative population sizes of predator and prey in past communities, such as North America at the time of human arrival about 12,000 years ago. If these prey animals show little evidence of food stress, then their population densities were low, probably due to intense predation by large predator carnivores. Under these conditions, the arrival of human hunters would have been more likely to lead to the extinction of prey species than if they were at high densities. Thus, this project can illuminate the possible role of humans in the late Pleistocene large mammal extinctions.
