BALTIMORE — MANY scientists believe that by transforming the earth’s natural landscapes, we are undermining the very life support systems that sustain us. Like bacteria in a petri dish, our exploding numbers are reaching the limits of a finite planet, with dire consequences. Disaster looms as humans exceed the earth’s natural carrying capacity. Clearly, this could not be sustainable.

This is nonsense. Even today, I hear some of my scientific colleagues repeat these and similar claims — often unchallenged. And once, I too believed them. Yet these claims demonstrate a profound misunderstanding of the ecology of human systems. The conditions that sustain humanity are not natural and never have been. Since prehistory, human populations have used technologies and engineered ecosystems to sustain populations well beyond the capabilities of unaltered “natural” ecosystems.

The evidence from archaeology is clear. Our predecessors in the genus Homo used social hunting strategies and tools of stone and fire to extract more sustenance from landscapes than would otherwise be possible. And, of course, Homo sapiens went much further, learning over generations, once their preferred big game became rare or extinct, to make use of a far broader spectrum of species. They did this by extracting more nutrients from these species by cooking and grinding them, by propagating the most useful species and by burning woodlands to enhance hunting and foraging success.

Even before the last ice age had ended, thousands of years before agriculture, hunter-gatherer societies were well established across the earth and depended increasingly on sophisticated technological strategies to sustain growing populations in landscapes long ago transformed by their ancestors.