Plenty of animals leap out of the water: whales, dolphins, flying fish, plankton. Yes, that's right, plankton. Those tiny microscopic creatures that are at the very bottom of the food chain do sometimes have the power to transcend their watery habitat, even if only for a brief moment. But some plankton can jump, and others can't, a puzzle that has confronted scientists for years. Now, there might be an answer. Like a lot of things in nature, plankton's ability to jump comes down to just two factors; speed and size.