ISOTOPIC ECOLOGY OF SMILODON FATALIS FROM NORTHERN KANSAS

The remains of extinct Ice Age animals along the north shoreline of Lovewell Reservoir in Jewell Co., KS have been professionally investigated for over 40 years. Taxa from this locality include: Camelops sp., Equus sp., Proboscidea, Smilodon fatalis, and Holmesina septentrionalis. Serial enamel samples were collected for stable isotope analyses from a S. fatalis canine reflecting ~20 months of growth. Stable carbon isotope values (δ¹³C) range from -4.7‰ to -6.6‰ (PDB) while oxygen isotope values (δ¹⁸O_water) range from -8.2‰ to -2.8‰ (VSMOW). Although undated, δ¹⁸O values from this animal have a similar seasonal range as modern surface water in the region, and exhibit even more elevated warm-season δ¹⁸O values. This is consistent with an age that is either interglacial or a warmer part of the last glacial period. More negative δ¹³C values could represent a more wooded landscape as would have been present during interglacials, or it could reflect more cool-season grasses as expected during the cooler Wisconsin glacial. Finally, ⁸⁷Sr/⁸⁶Sr of S. fatalis tooth enamel was compared to a regional Sr isoscape. Overall, these values indicate an annual range limited to central and eastern Kansas and Nebraska.