Taxonomy, location of origin, and health status of proboscideans from Western Canada investigated using stable isotope analysis

Authors

Jessica Z. Metcalfe, The University of Western Ontario
Fred Longstaffe, The University of Western OntarioFollow
Christopher N. Jass, Royal Alberta Museum
Grant D. Zazula, Government of Yukon
Grant Keddie, Royal British Columbia Museum

Document Type

Article

Publication Date

2016

Volume

31

Issue

2

Journal

Journal of Quaternary Science

First Page

126

URL with Digital Object Identifier

10.1002/jqs.2849

Last Page

142

Abstract

We investigated the application of stable isotope analysis of proboscidean remains (collagen in bone/dentin/cementum and structural carbonate in enamel bioapatite) for genus-level identification of isolated specimens, assessment of geographic origins, and testing for nutritional stress. Mammoths (Mammuthus sp.) tended to have higher δ¹⁵N_col and lower δ¹³C_col than mastodons (Mammut americanum), but differences were not significant in every location. Determining the genus of isolated specimens may be possible for locations and time periods with good isotopic baselines, but environmental changes can confound interpretations. For example, an Alberta proboscidean with a δ¹⁵N_col of +1.4‰ (characteristic of mastodons) ultimately proved to be a mammoth. Its surprisingly low nitrogen isotope composition is attributable to the recently deglaciated environment it inhabited. We provided a baseline for isotopic assessment of geographic origins of isolated proboscideans in Western Canada. Bioapatite δ¹³C_sc and δ¹⁸O_sc can be used to distinguish specimens from Alberta, Klondike, Old Crow, Herschel Island, and further south (e.g., Arizona, Great Lakes). Finally, we found that an Alberta mammoth with morphological evidence of nutritional stress experienced a change in diet, environment, or physiology prior to death, but its isotopic compositions did not suggest a link to hypothesized starvation (catabolism of proteins or reliance on lipids).