Functioning ’mechanical gears’ seen in nature for the first time
2013 09 13

From: Phys.Org

A plant-hopping insect found in gardens across Europe - has hind-leg joints with curved cog-like strips of opposing ’teeth’ that intermesh, rotating like mechanical gears to synchronise the animal’s legs when it launches into a jump.

The finding demonstrates that gear mechanisms previously thought to be solely man-made have an evolutionary precedent. Scientists say this is the "first observation of mechanical gearing in a biological structure".


This image shows cog wheels connecting the hind legs of the plant hopper, Issus.

Through a combination of anatomical analysis and high-speed video capture of normal Issus movements, scientists from the University of Cambridge have been able to reveal these functioning natural gears for the first time. The findings are reported in the latest issue of the journal Science.



The gears in the Issus hind-leg bear remarkable engineering resemblance to those found on every bicycle and inside every car gear-box.

Each gear tooth has a rounded corner at the point it connects to the gear strip; a feature identical to man-made gears such as bike gears – essentially a shock-absorbing mechanism to stop teeth from shearing off.

The gear teeth on the opposing hind-legs lock together like those in a car gear-box, ensuring almost complete synchronicity in leg movement - the legs always move within 30 ’microseconds’ of each other, with one microsecond equal to a millionth of a second.

This is critical for the powerful jumps that are this insect’s primary mode of transport, as even miniscule discrepancies in synchronisation between the velocities of its legs at the point of propulsion would result in "yaw rotation" - causing the Issus to spin hopelessly out of control.

[...]

Read the full article at: phys.org






Related Articles


Latest News from our Front Page

Pre-historic tokens used in conjunction with cuneiform
2014 07 22
An archaeological dig in southeast Turkey has uncovered a large number of clay tokens that were used as records of trade until the advent of writing, or so it had been believed. But a new find of tokens, dates from a time when writing was commonplace – thousands of years after it was previously assumed this technology had become obsolete. Researchers ...
Are immigration opponents Nazis?
2014 07 22
It seems the usual suspects are calling anyone who opposes unlimited immigration to be a "Nazi". The Left seems to be in constant fear of "Nazis" that lurk in public policy discussions and I assume under their beds. If you oppose any Leftist position, you are a.... take a wild guess...wait for it.... a NAZI! Tim Wise recently went ...
What Did US Spy Satellites See in Ukraine?
2014 07 22
Exclusive: The U.S. media’s Ukraine bias has been obvious, siding with the Kiev regime and bashing ethnic Russian rebels and Russia’s President Putin. But now – with the scramble to blame Putin for the Malaysia Airlines shoot-down – the shoddy journalism has grown truly dangerous, says Robert Parry. In the heat of the U.S. media’s latest war hysteria – rushing to ...
Oh, Great: Robots Are Set to Conduct National Security Clearance Interviews
2014 07 22
Advancing a career in the US government might soon require an interview with a computer-generated head who wants to know about that time you took ketamine. Psychologists at the National Center for Credibility Assessment (NCCA) are developing an interview system that uses a responsive on-screen avatar for the first stage of the national security clearance process. Initial screening for a variety ...
Is Anything on the Internet Real Anymore?
2014 07 22
Is there anybody…out there? I promise I’m a real person asking this question and typing this article…but beyond that, I can’t promise much else about anything you or I see on the Internet. This article on ZDNet, “GCHQ’s dark arts: Leaked documents reveal online manipulation, Facebook, YouTube snooping,” confirms — beyond a shadow of any possible doubt — that a barrage of ...
More News »