Cave Bear

The cave bear had a very broad, domed skull with a steep forehead; its stout body had long thighs, massive shins and in-turning feet, making it similar in skeletal structure to the brown bear. Cave bears were comparable in size to, or larger than, the largest modern-day bears, measuring up to 2 m (6.6 ft) in length. The average weight for males was 350 to 600 kg (770 to 1,320 lb), while females weighed 225 to 250 kg (495 to 550 lb). Of cave bear skeletons in museums, 90% are classified as male due to a misconception that the female skeletons were merely "dwarfs". Cave bears grew larger during glaciations and smaller during interglacials, probably to adjust heat loss rate. The morphology of the mandible of cave bears varied depending on climate; individuals in colder, drier, and more seasonal climates possessed more slender mandibles and a dorsoventrally smaller mandibular ramus relative to individuals living in warmer and wetter conditions. Cave bears of the last Ice Age lacked the usual two or three premolars present in other bears; to compensate, the last molar is very elongated, with supplementary cusps. The humerus of the cave bear was similar in size to that of the polar bear, as were the femora of females. The femora of male cave bears, however, bore more similarities in size to those of Kodiak bears.

The cave bear's range stretched across Europe; from Spain and the British Isles in the west, Belgium, Italy, parts of Germany, Poland, the Czech Republic, the Balkans, Romania, Georgia, and parts of Russia, including the Caucasus; and northern Iran. No traces of cave bears have been found in the northern British Isles, Scandinavia or the Baltic countries, which were all covered in extensive glaciers at the time. The largest numbers of cave bear remains have been found in Austria, Switzerland, northern Italy, northern Spain, southern France, and Romania, roughly corresponding with the Pyrenees, Alps, and Carpathians. The huge number of bones found in southern, central and eastern Europe has led some scientists to think Europe may have once had herds of cave bears. Others, however, point out that, though some caves have thousands of bones, they were accumulated over a period of 100,000 years or more, thus requiring only two deaths in a cave per year to account for the large numbers. The cave bear inhabited low mountainous areas, especially in regions rich in limestone caves. They seem to have avoided open plains, preferring forested or forest-edged terrains.

Dental microwear indicates that cave bears exhibited very high dietary flexibility and that their foraging habits differed substantially by region, often reflecting local availability of different food items. Cave bear teeth were very large and show greater wear than most modern bear species, suggesting a diet of tough materials. However, tubers and other gritty food, which cause distinctive tooth wear in modern brown bears, do not appear to have constituted a major part of cave bears' diets on the basis of dental microwear analysis, although other studies using dental microwear texture analysis (DMTA) have shown that cave bears consumed food with textural properties not distinct from extant bear species, with the exception of the polar bear. And at least one population, from Goyet Cave in Belgium, had DMTA values indicating a diet entirely composed of soft foods. Seed fruits are documented to have been consumed by cave bears. Cave bear dental microwear from the high altitude site of Ramesch-Knochenhöhle in the Totes Gebirge indicates that some cave bears living in mountains ingested large amounts of sand as a result of feeding on alpine vegetation. The results from Ramesch-Knochenhöhle also indicate two very distinct patterns of microwear among the same subspecies, which may potentially reflect differences in feeding behaviour between male and female cave bears. …