Have you seen spider webs on your wall? Do you know how spiders make their webs? This spider makes it from the silk threads that come out of the stomach. The glands contained in the stomach that serves to secrete the silk thread.
The great thing is how the spiders do not get stuck in their own webs, whereas other animals will be trapped inside them?
We need to know in advance that the spider web is composed of silk threads of various kinds, some are sticky and some are not.
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Lamarck, 1801 Source
There are two types of threads: there is a straight line like the fingers coming out of the center of the spider web and this is non-sticky, while the spiral in the spider web is a sticky yarn. Both types of threads of course have different functions.
The spider's prey like insects will stick to the spider web, but the spider will pass through the non-sticky part to eat it. And how does the spider get past this nonsticky yarn?
Spiders Claws
The claws on the spiders have different functions, among others, the spider has two to three small special claws at the end of each leg that serves to retrieve the strands of the spider web. So the spider can move quickly through the net without getting stuck with the sticky yarn part.
The other spider's claw is to associate the thread of the net. Spiders can use special claws to swing from threads to other strands without having to touch the sticky part of the web. So it can freely move on the webs.
Hair and oils Spiders
In spiders have short and dense hair clumps called scapulae that lie between the claws.
The end of each hair branched into the small hairs that look like a brush.
The function of the hair is to absorb moisture and make the spider's feet as if given a glue. With these feet the spider can walk through a smooth surface like glass. Some scientists also argue that spiders have certain oils on their bodies that cause spiders not to stick to their webs.
This oil makes spiders do not stick to the net and help not to get trapped inside the net itself. With a sticky web nest, the spider traps the tangled prey. But the spider never gets caught in its own web.
That is the mystery behind the fact how spiders can not stick to their own webs. And maybe this is one of the advantages that exist in this animal.
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