Nature of the beast? Complex drivers of prey choice, competition and resilience in Pleistocene wolves (Canis lupus L., 1754)

• Published in: Quaternary Science Reviews
• Main Authors: Flower, Lucy O.H., Schreve, Danielle C., Lamb, Angela L.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2021
• Subjects: Canis lupus
• Online Access: http://nora.nerc.ac.uk/id/eprint/531615/; https://nora.nerc.ac.uk/id/eprint/531615/1/JQSR-S-21-00405.pdf; https://doi.org/10.1016/j.quascirev.2021.107212

The wolf (Canis lupus L., 1754) has been a major keystone predator in the Palaearctic since the late Middle Pleistocene. Today, wolves display considerable dietary plasticity over their range, characterised by their preferential consumption of large and medium-sized wild ungulates, supplemented by smaller prey, including small mammals, fish and plant foods. However, the origins of this dietary flexibility (arguably the key to the wolf's long persistence) are poorly understood in terms of responses to different drivers over the course of the Pleistocene, including changing climate, environment and competition from other large carnivores. Here, in the first study using direct palaeodietary measurements on British fossil wolves, carnivore competitors and potential prey species, we compare stable isotope (δ13C and δ15N) evidence from three sites representing a late Middle Pleistocene interglacial (Marine Oxygen Isotope Stage [MIS] 7c-a, c.220-190ka BP), the early Devensian (last cold stage, MIS 5a, c.90-80ka BP) and the middle Devensian (MIS 3, c. 60-25ka BP). The results reveal clear patterns of changing wolf prey choice through time. Notwithstanding issues of collagen preservation obscuring some dietary choices in the oldest samples, both small and large prey (hare, horse) were taken by wolves in the MIS 7c-a interglacial, large prey only (reindeer, bison) during MIS 5a and a broader range of large prey items (horse, woolly rhinoceros, bison) during MIS 3. The results also reveal two further important aspects: (1) that where wolves and spotted hyaenas co-existed, they occupied the same dietary niche and the former was not outcompeted by the latter, and (2) that the stable isotope evidence indicates prey choices during MIS 7c-a and MIS 3 that are not in synchrony with palaeodietary reconstructions from previous studies based on wolf cranio-dental morphology. This establishes for the first time a likely lag between changing predatory behaviour and morphological response but is interestingly not seen in the wolves ...