What connects insects and cogs? © Getty Images

What connects insects and cogs?

Cog as in the wheel, not the Dutch shoe.

1. Planthoppers are insects of the Issidae family. They feed by sucking sap from the stems of plants and normally walk very slowly to avoid attracting attention from predators.


2. When threatened, planthoppers can leap over a metre, and can take off with an acceleration of more than 700G. When not jumping, the hind legs are ‘cocked’ back against a small spur.

3. The legs have to be fired backward within 0.03 milliseconds of each other to prevent the insect spiralling out of control. This level of precision isn’t possible using ordinary nerve impulses.

4. Instead, they are mechanically synchronised by a pair of cogs with teeth just 80 microns wide. This is the first documented case of working gears in nature.


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