Almost everywhere we went, humankind erased a world of wonders, changing the way the biosphere functions. For instance, modern humans arrived in Europe and Australia at about the same time – between 40 and 50,000 years ago – with similar consequences.

In Europe, where animals had learned to fear previous versions of the bipedal ape, the extinctions happened slowly. Within some 10 or 15,000 years, the continent had lost its straight-tusked elephants, forest rhinos, hippos, hyenas and monstrous scimitar cats.

In Australia, where no hominim had set foot before modern humans arrived, the collapse was almost instant. The rhinoceros-sized wombat, the ten-foot kangaroo, the marsupial lion, the monitor lizard larger than a Nile crocodile, the giant marsupial tapir, the horned tortoise as big as a car – all went, in ecological terms, overnight.