Scientists discover ‘skydiving’ spiders

“Flattie” spiders are more agile than cats in their airborne maneuvers.

To capture flatties for the new experiments, Yanoviak and his team climbed trees in the Panamanian jungle, where they climbed trees and popped plastic bags over any spiders that betrayed themselves by scuttling away.

And this creepy crawly’s aerial acrobatics are more advanced than mere gliding – it can change direction in mid-air.

According to National Geographic, if the spiders do happen to fall, they steer themselves through the air using movements of their outstretched forelegs. “Spiders generally rely on dragline silk … as a safety line should they fall”, she says.

The discovery came as a shock to researchers, who say there are no other instances of a spider displaying this kind of mid-air steering. They are “wafer thin”, Dudley said, and flexible; they maneuver by spreading their legs wide in order to use lift and drag to steer themselves toward the tree trunk when they fall.

Then, in the forests of both countries, the scientists dropped the spiders from a height of 65 to 80 feet (20 to 25 meters) above the ground.

“This study, like the first report of gliding ants, raises many questions that are wide open for further study”.

“These results are indeed surprising for a spider”, said Marie Herberstein, editor of the book Spider Behavior.

Just to make sure he subjected the eight-legged aeronauts to a drop test, which involved painting them orange to aid visibility and then throwing them from the top of the tree. What is the effect of their hairs or spines on aerodynamic performance?’

“The principal goal of this study was to document the occurrence of directed aerial descent in tropical Selenops species”, write Stephen Yanoviak, a biologist at the University of Louisville, and his colleagues. There is, however, no need for immediate concern that spiders will sprout wings.

The scientists finally auditioned large arachnids known as “flatties”, some of which live in the American tropics.

A gliding spider from the genus Selenops.

“After my collaborators and I discovered gliding behavior in tropical canopy ants, we started testing a broad range of wingless canopy arthropods (insects, spiders and crustaceans) for similar aerial behavior”, lead author Stephen Yanoviak of the University of Louisville Department of Biology told Discovery News.

‘If a predator comes along, it frees the animal to jump if it has a time-tested way of gliding to the nearest tree rather than landing in the understory or in a stream’.

Adds study leader Yanoviak, “It’s awesome to see them do it. They’re so good at it”.

‘As far as adult arthropods are concerned, only ants, bristletails and spiders use directed aerial descent, ‘ Yanoviak said.