Scientists have discovered that nature created mechanical gears long before man made cars and bikes – in the legs of a tiny jumping insect.
The baby Issus bug, a plant hopping garden dweller, has curved cog-like strips of teeth on each hind leg which interlock and rotate like mechanical gears to help it jump.
The discovery proves that gear mechanisms previously thought to be a solely man made invention were in fact first created by nature.
Scientists at Cambridge University made the discovery using a combination of body structure analysis and high-speed video.
‘We usually think of gears as something that we see in human designed machinery, but we’ve found that that is only because we didn’t look hard enough,’ said Zoologist and paper author Gregory Sutton.
‘These gears are not designed; they are evolved – representing high speed and precision machinery evolved for synchronisation in the animal world.’
Each gear tooth on the insect’s legs has a rounded corner at the point it connects with the other gears to stop teeth from shearing off when they clash, similar to gears on a bike.
The gears on the opposing hind legs lock together like those in in car gear box to make sure the legs are completely synchronised when they move.
This is critical for powerful jumps as even a tiny discrepancy in the timing between the legs would see, the little Issus spin out of control.
The legs always move within 30 microseconds of each other, with one microsecond equal to a millionth of a second.
‘This precise synchronisation would be impossible to achieve through a nervous system, as neural impulses would take far too long for the extraordinarily tight coordination required,’ said lead author Professor Malcolm Burrows.
‘By developing mechanical gears, the Issus can just send nerve signals to its muscles to produce roughly the same amount of force – then if one leg starts to propel the jump the gears will interlock, creating absolute synchronicity.