The Cave Lion (Panthera spelaea and Panthera fossilis)

[tigerluver]

@Polar , I would say the opposite. The American lion dropped high cursoriality and retained bone robusticity. I say this with scant data, but Reichenau's P. fossilis ulna was about as robust as those found by Merriam and Stock, while P. atrox's MT3/Femur ratio of about 0.33 and femur/tibia ratio of 1.17 indicates that it was not as tall and cursorial as P. fossilis. Thick bones go far into the African Panthera lineages, remember the 111 cm wide distal end of P. shawi. 

@GrizzlyClaws , I'll get back to you on the skull issue. Barnett et al. (2016) came up with the 1.89 mya divergence using just a P. spelaea and then assumed/inferred P. fossilis falls on that lineage. Not a bad assumption as P. shawi is found around that time, but not guaranteed until P. fossilis DNA somehow gets found, extracted, and tested. Reply