|MadSci Network: Environment & Ecology|
I've been pondering your question and from what I know about lions and leopards I am guessing the following. Leopards are generally solitary hunters with wide ranging food sources, eating anything from large ungulates to rodents, and they are also found in many different habitats. lions however are usually pack hunters and scavengers, even (I read somewhere) stealing food from leopards, they are also more limited in the habitats they can survive in. So I think that the 2 predators are very different which enables them to coexist, also since they aren't limited to only one food source if the lions eat the larger animals the leopards can survive on smaller prey. If you think about it lions and leopards are scarce anyway due to hunting so would they really encounter each other that often. The theory that there can only be one keystone species is a theory to be tested and I'm sure there are many other ecosystems that have more than one top predator. Of course we are forgetting that the top predator in the world is man!
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