October 15, 2012
By Karen Fox, ADA News staff
Cleveland—A group of Case Western Reserve University dental students and faculty spent their summer vacation exploring remains dating back as many as 200,000 years in an underground cave in Israel.
Anthropology: Case Western Reserve University School of Dental Medicine faculty members Bruce Latimer, Ph.D. (left), and Dr. Mark Hans prepare to accompany students on the Israeli excavation project. Photo by Susan Griffith
The trip forms one portion of an international project to search for insights into evolution. Working in conjunction with colleagues from the University of Tel Aviv, they planned to examine and recover bones and objects left by ancient cave dwellers under the mountainous city of Manot, Israel, near the border of Lebanon.
“It is part of the dental school’s ongoing scientific commitment to better understand human craniofacial biology,” said Dr. Jerold S. Goldberg, dental school dean.
Dr. Mark Hans, chair of orthodontics, planned the trip with Bruce Latimer, Ph.D., an experienced field anthropologist who joined the dental school as a visiting professor last year.
The excavation contributes to the department’s work in the area of human evolution and its connection to modern dental problems such as malocclusion, caries and periodontal disease, said Dr. Hans. The dig also aligns with CWRU’s work with the Legacy Project, a national online collection of major human growth and development databases. Dr. Hans maintains the Legacy Project’s Bolton-Brush Growth Study collection, a database of more than 200,000 radiographs that track human growth over eight decades.
Workers unearthed the historic cave near Manot during a 2008 construction project. The first object found 30 meters down on the cave floor was a partial skull, later determined to be that of a 58,000-year-old Neanderthal.
“The ground is covered with bones and tools,” said Dr. Hans. He said the fire pit, which served as a kitchen area, had charred animal bones and other debris that provides evidence of how the Neanderthals lived. He and Dr. Latimer believe much more is hidden beneath the surface.
Neanderthals were the first hominids to bury their dead, and they did it in their living spaces. Drs. Latimer and Hans expect to recover skeletal remains and more over the next decade from the layers of sediment that have filled the cavern’s floor.
Dr. Latimer said that human teeth and the face have changed dramatically over the past 6 million years. Modern man has a more vertical face, which differs from early hominids with jaws that protruded beyond the brain. In human evolution, teeth are a part of the body that survives the longest.
“Our analysis of these differences can provide insight into the development of the modern human face,” Dr. Latimer said.
Dr. Hans, who studies human facial development, said humans are the only adult animals that cannot eat and breathe at the same time. When teeth begin to appear and language starts to develop, changes occur in the mandible and maxilla jaw structure that close off the larynx position. As a result, humans now struggle with sleep apnea and choking, which are directly tied to these evolutionary craniofacial structural changes.