Size of the lower carnassial in the arctic and the red fox from Late Pleistocene in Belgium compared to other ancient and extant populations

Lengths, widths, and size proportions (length to width) of the lower carnassial were measured in 45 teeth of the arctic fox and 35 teeth of the red fox from Belgium radiocarbon dated to 46 640–14 120 ka BP. Data the Late Pleistocene foxes from Belgium were compared to 20 ancient and extant populations form Europe, Asia, and North America. The Pleistocene arctic fox from Belgium showed larger carnassial than in all recent samples of this species, whereas the Belgian fossil red foxes were characterized by the carnassial size comparable to that of the recent Siberian red foxes. Both fox species from the Pleistocene of Belgium showed the highest index of the carnassials length to width, which means increase in carnivorous adaptation. We conclude that the higher level of carnivorous specialization reached by the Belgian arctic and red foxes at the end of the Late Pleistocene reflected their scavenging on kills of large carnivores and human hunters (remains of megafauna). Harsh environmental conditions of that period and specific composition of ecosystems led to adapting to a more carnivorous food niche in both foxes.