Since time immemorial, when creating various mechanisms, people have been using what nature has already "invented". More recently, scientists have discovered in the hind limbs of the larvae of the small cicada insects Issus coleoptratus an organ that exactly resembles a gear.
Issus coleoptratus cannot fly, but they jump beautifully. The gear train helps them synchronize the movement of their hind legs during the push, with a mismatch of no more than 30 microseconds. As it turned out, this result could not have been achieved if the signals were transmitted through nerve impulses.
And this is not the only example. So some species of turtles use the growths along the edges of the shell, resembling a gear train, to protect against enemies. And in some insects, in turn, there are outgrowths like a comb, which they use to produce sound.