Humans may soon have to look to their laurels as the planet's dominant species. Turkeys, heretofore harmless, have been exploding in size, swelling from an average 13.2lb (6kg) in 1929 to over 30lb today. On the fairly scientific assumption that present trends will persist, The Economist estimates that turkeys will be big as humans in just 150 years. Before 6,000 years are out, turkeys will dwarf the Earth itself. Scientists and industry experts claim that the burgeoning of turkeys is largely the result of selective breeding. The fact that their growth is artificial, and that most have lost the ability to fly, suggest that all is not lost. Still, with nearly 250m turkeys gobbling in America, the only prudent course of action this holiday season is to eat them before they eat you.