Research Report
Tanya Smith (R) and co-PI Zarin Machanda (L)
Tanya Smith, Associate Professor at Harvard was awarded a Leakey Foundation research grant in the spring of 2012 for her project entitled “Tooth eruption and life history in living chimpanzees.”
Tanya Smith and her team study dental development patterns in chimpanzees in order to better understand the evolution of human development. Previous research on chimpanzee dental development has been performed on either captive animals or on deceased individuals, and it has been unclear whether the developmental trajectories derived from these data accurately reflect those of wild chimpanzees. So, Tanya Smith and her team set out to record dental emergence ages of living wild chimpanzees using novel photographic methods in order to generate a comparative sample of dental eruption standards and associated life history information.
The team photographed the Kanyawara community of chimpanzees in Kibale National Park, Uganda, over the course of three years. These data were then compared to long-term behavioral and life history datasets from the same population.
Two research papers have been published as a result of this project. In their paper published in PNAS, we learn how the eruption of the first molar in the Kayawara chimps compares to that of captive chimps as well as current estimates in australopiths. The second paper was published in the Journal of Human Evolution, and it describes how their comprehensive three-year record of dental eruption compares to records from captive chimps, living chimps from Gombe and deceased individuals at Taï.
In the report below, Smith summarizes the results of this project.