Roboticists made a splash last year by building a robot that duplicated one of the natural world’s niftiest tricks: jumping on water. Inspired by water striders — insects that can hop upward from watery surfaces — researchers at Korea’s Seoul National University and Harvard’s Wyss Institute for Biologically Inspired Engineering emulated the biomechanics necessary for their microrobot to vault 5.5 inches — more than 10 times its height — from water without breaking surface tension. Made from ultralight components, the tiny bot weighs just 0.002 ounce and gets its leaping power from a built-in catapult mechanism.