In terms of sheer biomass, the numbers are stark-staring: today people outweigh wild mammals by a ratio of more than eight to one. Add in the weight of our domesticated animals—mostly cows and pigs—and that ratio climbs to twenty-two to one. “In fact,” as a recent paper in the Proceedings of the National Academy of Sciences observed, “humans and livestock outweigh all vertebrates combined, with the exception of fish.”
