The 84th Annual Meeting of the American Association of Physical Anthropologists (2015)

Weaning trajectories with nitrogen and hydrogen isotope ratios in calcified tissues


1Department of Human Evolutionary Biology, Harvard University, 2Department of Human Health and Evolutionary Medicine, Cleveland Museum of Natural History

March 27, 2015 8:30, Grand Ballroom C Add to calendar

Nitrogen isotope ratios (δ15N) of tissues are frequently used in determining weaning trajectories in humans and primates. However, the method suffers from poorly-met assumptions, particularly in applications in the fossil record. Confounding factors include variability in isotopic offsets over time and between individuals and other biological effects on tissue δ15N, such as growth.

Teeth from experimental pigs show that hydrogen isotope ratios (δD) track weaning trajectories more reliably than δ15N, and may not require the same assumptions as the latter method. We extend the stable isotope corpus of δD in teeth with M1 and M2 roots of humans and chimpanzees, and assess this method in contrast to δ15N.