How Do Spiders Avoid Getting Tangled in Their Own Webs?

Renowned for their incredible strength and strong adhesive capability, spider silk enables them to ensnare all kinds of insects. But how do they avoid meeting the same fate as their prey?

Different types of silk

Spiders produce several varieties of silk using specialized glands. Located in their abdomen, these glands have their own excretory duct, ending in appendages called spinnerets. Solidifying as it leaves the arachnid’s body, the silk is spun by the movement of the leg, or by gravity if suspended. When combined, these substances allow the creation of webs that range from rigid to sticky.

Considered the most resilient, ampullate silk is used to construct the frame and radii of the web as well as the spider’s “safety line,” which must bear its weight. Paired with aggregated silk, the flagelliform silk is used to form the capture spiral, coated with an adhesive substance resembling glue.

If the specialized claws on the spiders’ legs help keep them away from the sticky areas, it turns out their limbs are also covered with branched hairs and a non-stick chemical coating. Features that, combined with their “sophisticated footwork” and their strategic placement, allow them to avoid trouble.

The Argyrodes Case

Among arachnids proving formidable in this little game, the members of the genus Argyrodes stand out, measuring between 3 and 12 mm. They parasitize the webs of Nephila pilipes, a spider species known for its extremely pronounced sexual dimorphism, with females reaching 37.50 mm against a mere 4.10 mm for males.

Contrary to what this marked size difference might suggest, it is the female N. pilipes who most often falls prey to the Argyrodes, patiently waiting for the right moment to strike, namely when they molt (a process during which they are temporarily defenseless).

To go further, also discover 14 spectacular uses that spiders make of their silk, as well as 9 of the world’s most dangerous spiders.