> intelligence has evolved in the animal world as a weapon of survival. Your point sounds interesting, but I'm not sure exactly what you mean. Are you saying

> intelligence has evolved in the animal world as a weapon of survival. Your point sounds interesting, but I'm not sure exactly what you mean. Are you saying that greater intelligence caused some species to crowd out their less-intelligent cousins? If so, how would we be certain of that? I mean, it seams plausible, but I'm not familiar enough with natural history to see why it's the best explanation for the historical record.