A species of horned beetle has a startling secret: a gearing mechanism in its mouthparts. The beetles beat us to the invention of meshed gears, possibly by millions of years.

Japanese rhinoceros beetles ( Trypoxylus dichotomus ) are found in east Asia. Males can be 8 centimetres long. This is unusually large for an insect, although not as large as male Hercules beetles that can reach double the size.

In Japan, the rhinoceros beetles are popular pets and are regularly depicted in anime and other media. “There is nobody who has …