CEM Seminar- B. Holly Smith

What Can Teeth Tell Us About the Evolution of Life Histories?

B. Holly Smith, Associate Research Scientist
University of Michigan
What can teeth tell us about the evolution of life histories?
All organisms face the challenge of allocating resources to growth, maintenance and reproduction. Human life history is constructed in some unusual ways that become evident when we compare ourselves to primates and other mammals, combing moderate size with large brains, slow growth and extended juvenile dependence, but a brief duration of nursing infants and the cessation of reproduction before senescence. If we could know the evolutionary history of our life cycle, we might test theories or scenarios by, at minimum, observing the order in which particular elements arose. But how much can we pull out of fossil teeth and bones about dynamic elements of the life cycle and energy use? Fortunately, humans, and mammals in general, develop in recognizable stages with patterned events in maturation of teeth and bone and tooth development is tightly integrated into the fabric of growth and development. This talk will explore, using examples across primates and other mammals, how tooth development can give us insight into the human fossil record, with a detailed look at weaning, tooth eruption and raising an offspring to independence—one of the principal ways humans differ from our closest relatives.
Holly's research interests include evolutionary biology, human paleontology, life history and dental anthropology. She is interested in how humans differ from other mammals in life cycle and life span, why we differ and whether we can reconstruct the evolutionary history of our life cycle from the fossil record.