>These ecosystems adapt to change very, very slowly, and birds and ants very gently come up against the carrying capacity of their surrounding environment, and

>These ecosystems adapt to change very, very slowly, and birds and ants very gently come up against the carrying capacity of their surrounding environment, and when they exceed that carrying capacity, their populations cease to grow and may waver, but will reach some equilibrium. They generally do not experience extreme boom and busts, except in extreme cases of invasive species and rapid climate change. This is closer to what I meant to say, and the term "exhaust" was a poor descriptor. However, the way in which species encounter barriers that define the carrying capacity of an ecosystem are not commonly gentle. >The difference with humans is that we use technology and agriculture to continually boost ourselves past the carrying capacity of our local environment, and when that becomes unsustainable--usually wreaking havoc all around us, we move on and spread. Just look throughout history. The pattern repeats over and over. I'm still uncertain at what point in our evolution you draw the line that cuts us out of the animal kingdom. I see your point, but you seem to be implying that the way you're using "equilibrium", and "natural" is rooted and biology, and this is incorrect. The there is no biological concept of "equilibrium", it's simply a way you could loosely describe a population with low rate of growth for some period.