This article is from the source 'guardian' and was first published or seen on . It last changed over 40 days ago and won't be checked again for changes.

You can find the current article at its original source at http://www.theguardian.com/science/2013/sep/13/gears-evolved-nature

The article has changed 2 times. There is an RSS feed of changes available.

Version 0 Version 1
Gears evolved in nature long before humans 'invented' them Gears evolved in nature long before humans 'invented' them
(5 days later)
A gear system similar to those used on bicycles has been found in insects, proving that nature developed cogs long before humans.A gear system similar to those used on bicycles has been found in insects, proving that nature developed cogs long before humans.
The juvenile Issus – a plant-hopping insect found in gardens across Europe – has hind leg joints with curved, cog-like strips of opposing "teeth" that inter-mesh, rotating like mechanical gears to synchronise the animal's legs when it launches into a jump, University of Cambridge researchers said.The juvenile Issus – a plant-hopping insect found in gardens across Europe – has hind leg joints with curved, cog-like strips of opposing "teeth" that inter-mesh, rotating like mechanical gears to synchronise the animal's legs when it launches into a jump, University of Cambridge researchers said.
The find demonstrates that gear mechanisms, previously thought to have been pioneered by humans, have an evolutionary precedent.The find demonstrates that gear mechanisms, previously thought to have been pioneered by humans, have an evolutionary precedent.
The gears in the Issus leg work in a similar way to those found on bicycles and inside car gear-boxes. The gear teeth on the opposing hind legs lock together like those in a car gear-box, ensuring almost complete synchronicity in leg movement. This helps with the powerful jumps the insects use to get around.The gears in the Issus leg work in a similar way to those found on bicycles and inside car gear-boxes. The gear teeth on the opposing hind legs lock together like those in a car gear-box, ensuring almost complete synchronicity in leg movement. This helps with the powerful jumps the insects use to get around.
Professor Malcolm Burrows said: "This precise synchronisation would be impossible to achieve through a nervous system, as neural impulses would take far too long for the extraordinarily tight co-ordination required.Professor Malcolm Burrows said: "This precise synchronisation would be impossible to achieve through a nervous system, as neural impulses would take far too long for the extraordinarily tight co-ordination required.
"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."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.
Co-author Gregory Sutton, now at the University of Bristol, said: "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.Co-author Gregory Sutton, now at the University of Bristol, said: "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.
"These gears are not designed, they are evolved – representing high-speed and precision machinery evolved for synchronisation in the animal world.""These gears are not designed, they are evolved – representing high-speed and precision machinery evolved for synchronisation in the animal world."
The gears are only found in juvenile insects and are lost as they pass into adulthood.The gears are only found in juvenile insects and are lost as they pass into adulthood.
Our editors' picks for the day's top news and commentary delivered to your inbox each morning.