Cave bear killers and scavengers from the last ice age of central Europe: Feeding specializations in response to the absence of mammoth steppe fauna from mountainous regions
During the last Ice Age of central Europe, cave bears hibernated deep inside their caves and Ice Age spotted hyenas used the cave entrance areas as dens. Steppe lions were also sporadic cave dwellers in order to hunt the herbivorous cave bears or steal prey from hyena dens, or for antagonistic and territorial reasons. Steppe lion skeletons recently discovered in the midst of cave bear skeletons, deep inside the Urşilor Cave (Romania), and steppe lion remains from other European caves, in particular a large population from the Zoolithen Cave in Germany, provide evidence of active predation by lions on cave bears. However, it was not mainly lions that fed on the cave bears: the large quantities of damaged cave bear bones, including incomplete long bones that repeatedly show similar types of damage, crushed long bones, and damaged skulls, reveal that hyenas were the primary scavengers on cave bear carcasses and were largely responsible for the destruction of their carcasses and bones. Predation and scavenging on cave bears (mainly by these two Ice Age predators but also by wolves and leopards) particularly in mountainous boreal forest environments that were devoid of the mammoth steppe fauna, explains the large quantities of fragmented cave bear bones that have been found all over Eurasia. The stress caused by these carnivores, deprived of their specialized ecological niche, may have led the herbivorous cave bears to hibernate as deeply as possible within their hibernation caves, in an attempt to protect themselves against predation. The felid predators were sometimes killed inside the caves, probably in conflicts with adult cave bears or even with hyenas, and remained as complete or only partly disarticulated carcasses.