Large, Gliding Spiders Discovered in South American Forests

Scientists found a species of jungle spiders that display impressive skydiving skills and they require no silk or safety line in the process.

In both forests, scientists dropped the animals from a height of up to 80 feet or 25 meters.

“We really did not expect to see gliding behavior in spiders”, said Stepen Yanoviak, a spider specialist at the University of Louisville.

The spider, from the genus Selenops, joins a small group of non-winged creepy crawlies that have the ability to maneuvre in mid-air instead of falling like a stone.

This particular predatory spider was the only one that the researchers found could glide.

Lead author Stephen Yaniovak and his colleagues at the University of Louisville have been looking for examples of gliding animals for years.

According to Berkley News, biologists in Panama and Peru have discovered a new type of nocturnal hunting spider that can steer their bodies and glide while falling so they can return to the tree they fell from. The first spiders used in the experiments failed the drop tests.

Professor Yanoviak believes the results of the study will provoke further research. After being dropped from the tops of trees, the spiders shown in this video are typically able to soar to the nearest tree trunk, providing the first evidence that spiders can glide.

It’s an unexpected talent for spiders, which have no history of either flight or wings, scientists say.

Ignoring the goose bumps though, these astounding Selenopoid spiders have managed to develop accurate and successful ways of preventing an escape from ending up horribly bad.

What they conclude is that a strong selective pressure in the environment exists against spiders that have otherwise uncontrolled descents from trees to the forest floor.

Dudley says he is interested in directed aerial descent because he thinks controlled gliding may have been the predecessor to flying, as animals learned how to use their arms and legs to gain lift in addition to maneuvering in freefall.

The spiders nearly always (93 percent of the time) maneuver in this way, gliding down a bit and then thwacking into the side of the tree, the researchers found. The landing doesn’t seem to hurt the spiders; because of their low mass, they don’t accelerate very quickly during the jump – they fall at a rate of about 9.8 feet (3 m) per second, Yanoviak said. “These include cockroaches, mantids, katydids, stick insects and true bugs”. What is the effect of their hairs or spines on aerodynamic performance?’ When falling, they get into a position similar to that of skydivers, spreading themselves out wide, which would allow them to move horizontally toward any tree trunk in the area.