Humans live in equilibrium with other species in a finite world. In such a world, there is never really a Steady State. Instead, there is a constant ebb and flow.  One species may be dominant in an area for a while, and then another. If populations are closely matched in “ability,” then the ups and downs aren’t too severe. If a predator depends on a particular type of prey for its dinner, it can’t eat all of the prey, or it will go hungry.

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