There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
Completely right GrizzlyClaws. In fact, lion evolution is much easier to understand, because it is not based in too many reinvasions and arbitrary events.
Lions-leopards-jaguars, the lion clade, seem to have evolved from a common ancestor in Africa about 3.5 million years ago. It was until 600,000 years ago that the first species, the cave lion (Panthera spelaea) emerged and invaded Europe and Asia up to North America. Latter, the lion separated from the leopard about 500,000 years ago and began they own evolutionary stories; jaguars evolved too from populations in Europe (P. o. gombazzoegensis) and later expanded also all Asia and up to America, reaching the entire continent.
So, the evolution of the lion clade is almost linear, with a few bottlenecks, while that of the tiger is similar in the earlier and middle Pleistocene (tigers suppressing/replacing other tigers) but the Toba eruption was a direct and abrupt change that stopped that normal tiger evolution and eliminated all except two genetic groups, that although closely related, probably already presented they own genetic variations. However, these variations are not very great, as a complete intermix was still possible (Sumatran tigers are the result).