On the wall of my weight room is a poster-sized print of the painting below, depicting North America’s wildlife at the site of California’s La Brea Tar Pits, 20,000 years ago: It’s a heartening image, reminiscent of the kind of biodiversity found only on the plains of Africa.

Familiar species still around today included peccary, deer, elk, coyote, bobcat, cougar, wolf and brown bear (the last two surviving species were hunted and trapped to extinction in California during the nineteenth and twentieth centuries), golden eagle, ravens and heron.

But the list of species once common, now extinct, on this continent is much longer. It includes American camels, horses, the California tapir, American mastodon and Columbian mammoth (two former representatives of the elephant family sorely missed on this continent today); also, a couple of now nonexistent bison (the giant and the ancient bison), three species of ground sloths: the Harlan’s, Jefferson’s and the Shasta (the latter, a mere daisy of a ground sloth compared to the 3,500 pound “giant” ground sloth).

They, as well as the stilt-legged llama and the dwarf pronghorn, the American lion, cheetah and saber-toothed cats, the dire wolf and the short-faced bear all disappeared shortly after the arrival of our species—the one blessedly absent from the scene at La Brea.

To me, the most beautiful thing about the painting is that the human species hadn’t yet shown up and started doing the damage they’re infamous for. Just pencil in a few stick figures and well over half the other species disappear. Sure, the genus Homo did less damage with stone-tipped spears than they could have with drones or AK-47s, but to the non-humans of the world, we were mighty dangerous and destructive nonetheless.

While many people nowadays harken back to a time before the emergence of modern technology and prior to the dawn of civilization—convinced that a harmonious era must have existed somewhere in human pre-history—when I pine for the good old days, this is the world I think of…