Faculty Profile:
Tom Reck

Faculty Reflection

Opportunities for Giving

Campus Collage

	These Teeth Aren't Flossed
	1997-98 Outstanding Teacher
	In the News
	With Respect
	Of Courses

Helping To Make CSU, Chico Better

Chris O'Brien (Ph.D., University of Wisconsin, 1994) joined the CSU, Chico Department of Anthropology as an adjunct professor in 1995, a neat trick because he also holds down a full-time job as assistant forest archaeologist with Lassen National Forest. His special skills bring a fascinating dimension to Chico State's archaeological studies program.

O'Brien specializes in dental increment analysis, a technique based on the study of tree-ring-like growth rings found in the teeth of large-bodied animals. While introduced and used most heavily by wildlife biologists, archaeologists have employed dental increment studies to determine the age and season of death of animals found in archaeological sites. This kind of information can be used to reconstruct the season of use of sites, characterize the properties of game herds exploited by prehistoric hunters, and even evaluate predator-prey dynamics expressed in the relationship between ancient human hunters and the game that they hunted.

Dental increment analysis requires a well preserved tooth, best retrieved from buried deposits or rockshelters and caves, all contexts that tend to provide the best conditions for the preservation of organic remains. To conduct the analysis, the tooth is first identified by species. The whole tooth is then mounted in an epoxy block, which, when set, is cut to make a thin slice. Additional grinding produces a readable thin section. A high-powered microscope and digital imaging system available in Chico State's archaeometric lab is used to identify and define the growth ring phenomena. O'Brien's active projects reveal the range of interesting and useful archaeological/ecological implications of dental increment findings.

O'Brien is still expanding his dissertation research, which spanned several field seasons in Kenya, east-central Africa. His field work involved two components: (1) visits to a major game ranch to collect specimens representing documented kills from thoroughly managed herds and (2) travel over the open countryside with a nomadic hunting band known as the "Hadza" to collect specimens from kills made by hunters seeking food for the band. In both contexts, he collected the teeth from big game kills, eventually collecting and analyzing over 1,500 teeth representing seven game species (primarily zebra, wildebeest, hartebeest, and impala). The game ranch specimens provided a control group, taking advantage of tags and records to determine independently the precise season of death, and thus enabling him to calibrate the method. With the Hadza, he observed how his hosts selected, hunted, and processed animals, and then he collected the teeth after the kill was butchered. His combined findings built a body of information intended to help archaeologists understand and identify the seasonal differences they might find between short-term kill sites versus base camps. Currently, he is re-examining his field records to reveal and compare the dynamics of human-game interaction at both the game ranch and among the Hadza. His data reveal that -- as a result of seasonal changes in game herds associated with calving and predominance of certain age-sex herd groups, and seasonal changes in human take and technology associated with aggregation and dispersal patterns -- hunter-gatherers could have generated a significant impact on the density and distribution of large game species. He is engaged in additional studies in northeastern California and elsewhere with the goal of further exploring and testing this proposition.

O'Brien is pursuing several other projects with the assistance of Department of Anthropology graduate students:

An analysis of black-tailed deer teeth from archaeological sites located in the Ishi Wilderness. Dental increment studies will be used to establish the nature and change over time in the general demographic profile of deer herds hunted by the ancient inhabitants. This study is being done in consort with Lassen National Forest, which hopes to use the results to establish baseline conditions for contemporary herd management.

An analysis of bison teeth from a late prehistoric "buffalo jump" site in Wyoming. Dental increment studies will be used to determine the season of use and the demographics of the herds.

An analysis of bighorn sheep teeth for the California Department of Fish and Game. Dental increment findings will be compared with other methods of determining age and season of death in the hopes of improving DFG's herd assessment and management practices.

An analysis of pronghorn teeth from an accidental kill location in Montana. In winter 1990 during extreme fog conditions, a complete herd of 150 pronghorn walking single file stepped off, one at a time, a steep cliff face. All the animals died at the base of the cliff. Because they all died at the same time, it will be possible to hold seasonality constant and evaluate the nature and extent of dental increment variation by age, sex, or other categories.Chris O'Brien hopes to increase CSU, Chico faculty, staff, and student research opportunities via the dental increment lab, as well as develop the scientific understanding of forest resources.

Greg White, Archaeological Research Program and Department of Anthropology
(Note: White has been the recipient of an impressive array of contracts and grants lately, totaling in the tens of thousands so far and including grants for research in Turtle Creek from the Bureau of Land Management in Redding, in Squaw Valley from Plumas National Forest, and in Ishi Wilderness from Lassen National Forest, plus one for the Society for California Archeologists' newsletter of which he is currently editor. On the docket and possibly totaling a six-figure number, White awaits contracts for field reviews from the California Department of Forestry, and for research in the Guadalupe Parkway from Cal Trans, in Cache Creek from the Bureau of Land Management in Ukiah, in MacKerricher State Park from the Department of Parks and Recreation, in Carmen Valley from Tahoe National Forest, and another in Squaw Valley from Plumas National Forest.)