Researchers from the University of Adelaide and elsewhere have sequenced and analyzed mitochondrial DNA from fossils of cave lions (Panthera spp.) and brown bears (Ursus arctos), two megafaunal carnivorans that dispersed from Eurasia into North America during the Pleistocene, to better understand the timing and drivers of their past movement between the continents across the Bering Land Bridge. Their results reveal striking synchronicity in the population dynamics of Beringian lions and brown bears, with multiple waves of dispersal across the Bering Land Bridge. The evolutionary histories of these two megafaunal animals underline the crucial biogeographical role of the Bering Land Bridge in the distribution, turnover and maintenance of megafaunal populations in North America.