Rancho La Brea stable isotope biogeochemistry and its implications for the palaeoecology of late Pleistocene, coastal southern California

This work measured carbon and nitrogen stable isotopes in bone collagen from Rancho La Brea mammals, including the predators Smilodon and Panthera atrox alongside their herbivore prey. The isotopic signatures reconstructed the structure of the food web and the vegetation backdrop of late Pleistocene coastal California. Results indicated a landscape dominated by C3 plants rather than open grassland, and the predator values pointed to diets centred on large browsing and mixed-feeding herbivores. By placing sabertooths and American lions within a quantified trophic framework, the study moved discussion of fossil felid diet from anatomical inference toward direct geochemical evidence, and established baseline isotopic data still used in megafaunal palaeoecology.