COOPERATIVE INSECTS. “In a world full of things that are much, much bigger than they are, insects manage to do pretty well with getting around. Some of the most successful insects are the social and cooperative ones, like ants, which can do incredible things such as using their bodies to create structures to get themselves across rivers.”
http://spectrum.ieee.org/automaton/robotics/robotics-hardware/robot-roaches-with-tiny-magnetic-winch-cooperate-to-scale-steps