We have managed for 10 000 years to shovel cultivated foodscabbage and grain, venison and other game, tidbits of veal, honey, fermented grapes, ripe passion fruit, and a thousand other epicurean delicaciesdown our throats, converting ever more of the planet into humans. Now, in consequence, there is no ecological opportunity on the earth to compare with the gigacaloric potential of human flesh. Each mouthful we eat adds its incremental Darwinian pressure on the viral and bacterial communities to evolve to make a diet out of us. So far they have made only limited evolutionary progress. But many microbiologists believe this is the real green time bomb, rather than the greedy things we do to resources or the indelicate things to the balance of nature. The human tombstone will then read: "Thus is the biter bitten."