As fascinating and just plain weird as the deep-sea geothermal vent ecosystems are, they have a great deal less diversity than we find in ecosystems that receive direct sunlight. At deep-sea vents we’ve counted about 1,300 species so far. In the Amazon rain forest, we can find 40,000 species of insects, just insects, in a typical square kilometer. Couple that with trees, monkeys, spiders, and snakes, and the rain forest has thousandfold the diversity.