![]() Ballooning spiders have been found floating more than two miles high and thousands of miles out at sea. Similar to bridging, numerous spider species are able to “balloon” up into the sky by releasing strands of silk that get picked up by the wind and Earth’s electrical fields. “And then I’d be remiss not to mention how spiders can fly,” says Echeverri. The arachnid doesn’t really know where it’s going, of course, but it beats crawling. Most spiders are tiny, but they can travel between trees or across enormous gaps through a process known as “bridging.” All the spider needs to do is let out a line of silk into the wind and then pull it taut once it connects to something out in the world. It even allows change directions once they’re airborne with a quick tug of the drag-line. This allows jumping spiders to crawl back to where they started if they miss their mark. They protect themselves against falls by anchoring a silk safety line to their perch. Jumping spiders are constantly leaping across chasms, for instance. While silk is an excellent building material, it can also be used for transportation. “That’s a spider that just defies most spider-like things,” says Echeverri. Once back in their underwater vegetation dens, they then wipe these bubbles off and bring them into the web to form a tiny, oxygen-rich sanctuary where they can hide from predators and lay eggs. These spiders can’t breathe underwater, though, so they make repeated trips to the surface to capture air bubbles with specially adapted hairs. “So, this is a spider that lives its entire life underwater by tying together some vegetation with its silken web,” says Echeverri. “And when prey walks along the tunnel, the spider feels the vibrations, and it will actually run up on the inside and bite through the silk and grab the prey with its fangs, envenomate it, and drag it back inside.” “You will almost never see the spider, because it is inside of that tunnel and it extends into the ground,” says Sebastian Echeverri, an arachnologist and science educator at the University of Pittsburgh. Gnaphosids shoot silk at their prey like Spiderman. These clever creatures lure moths in close with pheromones and then swat the insects out of midair with a single piece of sticky, weighted silk that they swing around like a mace. In the tropics, there are even spiders in the Nephila genus that infuse their silks with carotenoids, which, when the sun hits them, makes the webs seem as if they were dipped in liquid gold.īolas spiders skip web-building altogether. On the other side of the spectrum, there are spider silks that reflect ultraviolet light and appear blue at certain angles. “Some spiders produce a silk that is low in UV reflection and is also translucent, so insects can’t see it,” says Catherine Craig, an evolutionary biologist and author of Spider Silk: Evolution and 400 Million Years of Spinning, Waiting, Snagging, and Mating. When ants or crickets brush up against one of these tendrils, the line snags the prey and then snaps, drawing the helpless creature up into the air where it will dangle until the redback decides to eat it. The redback spider of Australia spins a tangled web with sticky, “gum-footed” lines that stretch straight down to the ground like a beaded curtain. (Read about the spider that uses its web to shoot itself faster than a rocket.) Spiders in the Theridiosomatidae family build conical webs that can fire a spider at nearby prey like a slingshot, while ogre-faced spiders nab their meals with hand-held nets. Black widow webs are messy affairs, while funnel webs and lampshade webs can resemble three-dimensional sculptures. ![]() There are horizontal sheet webs that catch falling prey and vertical latticework webs that intercept flying prey. A common orb-web, for example, may contain at least four different kinds, each adding a different component, such as strength, flexibility, and stickiness.Įquipped with such a versatile material, spiders have evolved to create a wondrous assortment of webs. Some spiders can produce more than one type of silk. Actually a protein created by special organs known as spinnerets, spider silk can be used for transportation, shelter, courtship, and all kinds of creative ways to trap prey. Spider silk is one of the most versatile materials on Earth.
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