Researchers have cracked the science behind “flying” spiders that leap long distances through the air while scaring onlookers witless.
And — just when you thought the creepy crawlies couldn’t get any more terrifying – their aerial acrobatics are all down to electricity.
Scientists have long grappled with the riddle of aerodynamic arachnids that mysteriously glide through the air for hundreds of miles.
Most notably, biologist Charles Darwin documented the phenomena in his diary in the 19th century.
They’ve long believed that the flight of the wingless bugs is due to a process known as “ballooning,” which sees spiders weave fine silk threads that catch in the wind and catapult them over great distances at high altitudes.
But that doesn’t explain how they manage to propel themselves when there are no gusts to speak of, or on cloudy days and in rainy conditions.
Well, biologists from the University of Bristol claim they’ve found the answer.
The arachnids are actually getting a boost from the atmosphere’s static electricity – the same charge that makes your hair stand on end when you rub it with a balloon or beanie – claim the boffs.
They put their theory to the test in a new study, published in the journal Current Biology, creating their own atmosphere isolated from ambient air inside a makeshift box.
This allowed them to shut out the electrical field present on Earth, replacing it with their own manufactured electrical field that they could switch on and off.
Inside the box went a small spider from the genus Erigone, which lead author Dr. Erica Morley described as “frequent astronauts.”
When the artificial electrical field was turned on, the spiders did indeed balloon – the likely cause of which is the spiders’ sensory hairs known as trichobothria, claim the researchers.
And when it was turned off, the spiders would glide down.
The researchers concluded that the electrostatic forces are enough to make spiders fly, but they probably rely on winds as well.
“Previously, drag forces from wind or thermals were thought responsible for this mode of dispersal, but we show that electric fields, at strengths found in the atmosphere, can trigger ballooning and provide lift in the absence of any air movement,” said Morley.
“This means that electric fields, as well as drag, could provide the forces needed for spider ballooning dispersal in nature,” she added.
So the next time you see a spider leaping at you, take a moment to marvel at the science behind its mid-air theatrics.
Actually, scratch that, just run away screaming as usual.
