Cave Bear Skull - Ursus spelaeus

This skull measures 20.5 inches long,

Back of skull to front of teeth. Straight line measurement, not following the curvature of the skull. 

Massive skull!!!!

The Cave Bear was a very large species of bear common in Europe during the Pleistocene and extinct by the beginning of the Last Glacial Maximum about 25,000 years ago.

The Cave Bear\'s range stretched widely across Europe, and undisturbed caves often contain their remains. Their occurrence in known sites of early human art, such as Chauvet and Lascaux helped to associate them with Neanderthals and Cro-Magnon man, an idea further popularized by Jean M. Auel\'s 1980 novel Clan Of The Cave Bear.

Death during hibernation was a common end for the Cave Bear, and while sheltered from the elements, its bones were often attacked and disarticulated by Cave Hyenas and other scavengers. 

Recent reassessment of fossils suggest the cave bear may have died out some 27,000 years ago. Though the reason is still disputed, the timing suggests that habitat loss due to climate change may have been responsible.

Reference.