A young planthopper insect, common to many countries across the globe, has been found to house quite a unique secret. Researchers have made the incredible discovery that these small creatures possess biological gears, capable of interlocking with one another to generate high-velocity pouncing.
The research team published their surprising results in the latest edition of the journal Science. They indicate the finding of these gear structures to be atypical of most animals. Not only this, but the manner in which these gears are reported to interlink and rotate, with functional purpose, has never been reported in nature before.
The planthopper insects (Issus Coleoptratus) can use the miraculous mechanism to soar distances of approximately three feet. Their rear legs move at incredible speeds of just 30 microseconds of one another, facilitating rapid and powerful jumps.
Scientists have encountered other animals that possess similar “gear-based” structures, but they remain functionally useless. For example, the cog-wheel turtle harnesses a series of gear-like projections jutting from their shells, but they are principally for display.
Burrows managed to study the rapid movements of the young planthopper, alongside his colleague Gregory Sutton, with the aid of a high-speed camera capable of rapid shutter speeds. The young creatures were primed in the correct position, using a waxy substance. Their undersides were then stroked to prompt them to jump, and the results were recorded in astonishing detail.
The gears are described as asymmetrical, in contrast to industrial gears. According to Malcolm Burrows of the University of Cambridge, England, who is involved in the study of animal movements, this asymmetrical design is no anomaly. He specifies such non-uniformity is critical to the young planthopper’s ability to jump vast distances by ensuring the gears can only rotate in a single direction.
Without the use of these biological gears, the young planthopper would experience difficulty coordinating, due to inappropriate orientation of its hind limbs, and its attempts at pouncing would simply culminate in the creature’s body spinning around.
Molting, Gear Losses and the Nervous System
This ability is eventually lost, as the juvenile planthopper transitions into its adult form. The amazing gear-like structures are cast off, during the molting process. Alternatively, the adult variants must rely upon rapidly rubbing their hind legs to achieve synchrony, prior to launch.
Burrows hypothesizes that the loss of this extremely useful ability could be the result of a biological design flaw, so to speak. Young planthoppers seem to molt up to five times, prior to becoming fully developed, a process which becomes lost in adulthood. Burrows imagines that this molting helps to replace these gear-like structures. Essentially, if adult planthoppers were not provided a different means of jumping, and the gears then “broke” during a their lifetime, it would result in permanent disablement, and no means of escaping predation.
Burrows suggests the creature’s nervous system would be unable to control synchronization of the legs, as it would be too slow in delivering neural impulses. By transmitting a nerve signal to the muscles, the same amount of force is produced in each leg. However, under the circumstances that one of the limbs begins to propel the jump, the gears will intertwine to generate perfect synchronicity.
Other Natural Examples?
Sheila Patek, a researcher working for Duke University, North Carolina, says there is likely other organisms with naturally occurring gears. According to the National Geographic, she described her shock upon hearing the discovery:
“What surprised me is that [Burrows] found it in a particular stage of development, and it goes away in adult stages… It’s definitely a wonderful discovery.”
When considering the planthopper is a little bigger than a flea, and is capable of pouncing at lightening speeds, it’s little wonder that scientists had failed to perceive the use of these tiny biological gears. Nonetheless, if scientists continue to look, these natural structures might conceivably be found in a number of other organisms.
By: James Fenner