The plant hopper Issus coleoptratus has natural gears that synchronize the action of its hind legs during a jump.
If you are a young plant hopper, leaping one metre in a single bound, you need to push off with both hind legs in perfect unison or you might end up in a spin. Researchers have discovered that this synchrony is made possible by toothed gears that connect the two legs when the insects jump.
The jumping mechanism of the plant hopper Issus coleoptratus is made possible by the joints that connect the hind legs to the body. They have rounded shapes and a series of tiny intermeshing teeth, each about 20 micrometres long.
When the insect jumps, the cog teeth join so that the two legs lock together, ensuring that they thrust at exactly the same time. The gears add an extra level of synchronization beyond that which can be achieved by the nervous system. Learn more here, here or here.