Megafauna

For most of life's history, predators and their prey pushed against each other through gradual adaptations, each change barely shifting the chances of surviving another day. The natural order stayed balanced for a long time.

That balance broke with the arrival of our species. Humans gained the ability to devise new tools and new ways of behaving, which let them get past natural defenses far faster than evolution could respond. As people spread out of Africa, most of the world's megafauna disappeared, including mammoths, sabertooth cats, sloths as big as elephants, and a great many other species.

Humanity's inventiveness has now grown to a scale that threatens to make the planet uninhabitable, including for us. The very capacity that caused this destruction, the analytical and creative power of the human brain, is also the only tool we have to counter it.