We thought that gears were human inventions… Yet according to the research made by a group of scientists led by neurobiologist Malcolm Burrows and published in Friday’s edition of the journal Science, this basic mechanism now turned up in the legs of young planthopper insects. This provides the first known example of working gears that evolved in a living being.
While examining flightless planthopper insects in the genus Issus, University of Cambridge neurobiologist Malcolm Burrows discovered that the young insects’ legs had gear teeth that locked into place while jumping. The adult planthoppers lose the gears when they’re fully grown, having developed strong enough legs.
“We weren’t deliberately looking for it. Why would we?” said Burrows, “There’s been no description of gear wheels functioning in animals before. “
Researchers used a high-speed camera to photograph those hardcore – they can endure roughly 500 Gs while moving – jumpers while they jumped. That’s when they spotted the gear teeth on the insects’ legs.
Each gear strip was about 350 to 400 micrometers long — about half as thick as a credit card — with about 10 to 12 teeth in each.