A species of Yeti crab (Kiwa puravida) recently discovered at the bottom of the Pacific Ocean may be the world’s deepest farmer. Scientists from the Scripps Institution of Oceanography in La Jolla, California, and elsewhere, diving in the research submarine Alvin, collected the crabs 3,300 feet below the ocean surface off the coast of Costa Rica. The crabs have a specialized whip-like appendage that scrapes the bacterial filaments from their claws and scoops the meal into their mouths. As it happens, these deep-sea bacteria feed on chemicals from seafloor hydrothermal vents, which release plumes of methane and sulfide. The researchers saw the crabs waving their claws rhythmically over the vents: They were apparently fertilizing their crops.