David Podlesak, University of Utah Stable isotope analyses of animal tissues gives information about their diets Sequential analysis of hair, ivory and tooth enamel provides the opportunity to study dietary history. In this study we propose to use sequential isotope analysis of elephant hair, ivory, and molars to quantify the life history of a single individual elephant. This will give insight into the life history of elephantids and will provide a model for the interpretation of fossil mastodonts, mammoths, and elephants in the geological record. We will study an individual with detailed observations taken from 1996 to 2006 by Save-The-Elephants Foundation; this ca. 55 year old individual died on 26 Sept 2006 and various tissues were recovered (ivory, hair, molars). This individual was tracked by GPS (Global Positioning System) for 4 years between 2001 and 2006 (the collar failed during part of this time); hair samples were collected on 5 occasions between 2001 and 2006. Four known pregnancies and births are known between 1996 and 2006. We will use the bomb 14C record to determine the growth rate of the tusk and reconstruct a detailed isotope history using collagen and bioapatite in the tusk. We will also analyze hair samples collected on known dates between 2001 and 2006. We will construct a detailed life history through stable isotope analysis of 13C/12C, 15N/14N, and 18O/16O ratios in ivory; we anticipate a 50-year record to be preserved in the ivory. Tusk histology, climate records, visual observations over a 10-year period, GPS records, and satellite measurements of vegetation response to rainfall (NDVI: Normalized Difference Vegetation Index) will be combined with stable isotope records to reconstruct a life history of single individual which will provide a model for interpreting fossil mastodonts, mammoths, and elephants. We will use the detailed ivory history to reconstruct maturation parameters for elephant molars which then can also be used to reconstruct seasonality in even older fossils where diagenesis may have compromised the isotope record of ivory.
