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.
If all living animals were living in a single great landmass, one huge continent, as it sounds like where this debate is being described, I do not believe that one or two big cat species would terminate the others. Modern day lions are dynamically suited for hot dry climates in open terrain. I don't believe that they would begin living in forests already occupied by tigers. Neither do I think that tigers would suddenly begin hunting in the savanna already occupied by lions. Certainly there would be confrontations in isolated instances in locations bordering between grassland and forest, but neither the lion nor the tiger would force the other into extinction.
I do believe that there would be some heavy competition between the leopard, jaguar, and the non-pantherine cougar especially in forests and jungles. But they would learn the pecking order and should be able to coexist.