Hadza oral health research

Team Members: Peter S. Ungar, Alyssa Crittenden, John Sorrentino, Jerry Rose

Funding Source: US National Science Foundation

Our group examined oral health in the Hadza peoples of Tanzania, the last remaining hunter-gatherers in Africa. Our research has focusing on changes in caries rate, periodontal disease, orthodontic disorders and developmental defects associated with the transition from foraging for wild foods to an agriculture-based village subsistence.

Predmostí canid microwear

Team Members: Kari Prassack, Peter S. Ungar, Josie DuBois,  Martina Laznickova-Galetova, Mietje Germonpre.

We examined microwear textures on the carnassials and postcarnassial teeth of fossil canids from  the site of Predmosti in the Czech Republic.  Some researchers have distinguished “protodogs” from wolves at this important Upper Paleolithic site, and hence Predmosti is an important key to debates concerning the initial domestication of dogs.  Our project contributes to the discussions by testing the hypothesis that samples identified as protodogs had different diets than those recognized as wolves.

Dental biotribology and microwear/nanowear formation

Team Members: Jing Xia, Peter S. Ungar, Licheng Hua, Zhong-rong Zhou, Jing Zheng, Linmao Qian, David Daegling, Jean-Francois Meullenet, Ryan Tian.

Funding Source: The National Academy of Science of China, Southeastern Conference

We used principles from engineering to study the tribological properties of teeth.  Our work has focused on the etiology of microwear and nano-scale tooth wear in light of the biomechanical and chemical properties of tooth enamel.  This has involved a series of in vitro experiments involving chewing machines, nanoindentors, atomic force microscopes, instron machines and other instruments to work out the conditions and processes underlying the removal of enamel tissue from tooth surfaces.

Relationships between dental topography and diet in platyrrhine primates

Team Members: Carrie Healy, Aleksis Karme, Mikeal Fortelius, Peter Ungar, Mark Teaford

Funding Source: LSB Leakey Foundation

This project involved generating and laser scanning high-resolution replicas of the upper second molars of 341 wild-caught individuals from 16 species of platyrrhine.  Specimens were grouped by reported dietary preference into frugivores, gummivores, folivores, and seed eaters.  Additional analyses were conducted on the frugivores alone, separating those that
supplement their diets with hard objects, insects, leaves, and seeds.  Results indicate that each  preferred diet type shows a distinctive combination of occlusal slope, relief, angularity,  sharpness, and orientation patch count (rotated) for given gross wear categories. Furthermore, among the frugivores, secondary diet groups were also well separated.