Fossil in the cave bear (Ursus spelaeus), a relative on the brown bear and polar bear in the Pleistocene epoch in Europe The subfamily Ursinae expert a extraordinary proliferation of taxa about five.3–four.five Mya, coincident with important environmental changes; the initial users on the genus Ursus appeared around this time. https://www.youtube.com/channel/UCCoZfLHRsYsRsVHqS-CSAWA