Spiders are fascinating creatures. They are master spinners, architects, and structural engineers all rolled into each tiny eight-legged body. However, most humans have an inherent fear of spiders.
At Halloween, fake spider webs are frequently incorporated in scary décor. It makes you wonder, how do spiders actually make webs? That’s what we’ll discuss in this article.
If you have ever accidentally walked through a real spider web, you know the feeling of panic and sudden improvised karate moves to get it off. But in reality, each spider web is a tiny masterpiece that should fill us with wonder at these incredible arachnids.
How Do Spiders Make Webs?
Spiders make webs using a silk thread that is excreted by the spinneret. The spider controls the thread’s thickness, texture, and adhesiveness as it’s drawn from the spinneret depending on the thread’s intended purpose. Most spiders have three spinnerets, some up to 8, for different thread sizes.
Spiders are special in their ability to produce silk. The silk, which is in a liquid form, is excreted from an organ called a spinneret, located at the rear base of the abdomen.
A spider’s spinneret is amazing as it allows the spider to decide the thickness of the silk required, if it should be sticky or not, and if the thread should be smooth or rough. The silk starts as a liquid but dries and solidifies when exposed to air.
Like a net, the edges of the spider web are anchored onto strategic points to hold the net open and taught; these are known as frame threads. Once the external frame threads and anchor points have been established, the spider fills the void between the frame with radial and viscid threads.
Radial webs run from the middle to the edge, while the lateral threads are called the viscid threads. Mooring threads may also form part of the web. These are the long threads you may see extending out from the web onto an anchoring point.
The spider excretes the silk strands as it crawls along in a unique pattern that then forms the spider web’s elaborate design. Each thread is precisely placed to maximize the chance of catching an insect in the net.
This video shows a Garden Orb Web Spider building a web, wonderfully recorded in time-lapse by BBC Earth.
Why Do Spiders Build Webs?
Spiders build elaborate webs to trap insects that the spiders eat. The spider webs silk fibers are coated with a sticky substance that prevents an insect from escaping once it has flown into the web. When the insect struggles when trying to free itself, the insect becomes entangled in the web itself.
Spider webs, also known as cobwebs, are a great way of catching food without the spider needing to run after and catch the prey animal physically. The spider lies in wait in the middle of the web for easy and fast access to the prey item when it lands in the web. A swift bite from the spider injects venom into the insect; this quickly kills or paralyzes the victim and allows the spider to enjoy the insect at leisure.
Do All Spiders Make Webs?
Not all spiders build spider webs as we know them. Some spiders are ground-dwelling and lie in wait for an unsuspecting insect to pass by before grabbing it.
Other spiders carry a small net or web along with them. The web is tossed over its unsuspecting prey to catch the prey.
How Strong Is A Spider’s Web?
The individual strands of a spider’s web are incredibly strong. Size for size, the silk is far stronger than steel. The spider web design combined with the strong silk threads makes it very hard for an insect to break out of a web once caught.
Do Spiders Eat Their Spider Web?
Many spiders do eat their spider webs. Spider webs lose their stickiness over time which makes them less effective in capturing food for the spider.
Ingeniously, the spider recycles its web by eating it. The silk thread from which the web is made has a very high protein content.
Are All Spider Web Designs Similar?
Not all spider webs look the same, but most share basic design principles without which the web would not have its characteristic shape. Of course, spider webs are found in many locations, both in homes or out in the wild. There are roughly forty-eight thousand spider species in the world, so web designs vary widely.
Commonly found on all spider webs are the following silk threads that aid in creating the spider web.
- Mooring threads – Long threads that attach to the frame threads and act as the main anchor lines.
- Frame threads – Create a frame around the web to which the inner threads are attached.
- Radial Threads – Threads run from the center of the web to the outside, attached to the frame threads
- Viscid threads – Also called the orb threads, are the thin threads that run between the radial threads and are sticky to trap the insects.
Are Spider Webs Sticky?
The silk threads of a spider’s web are covered with sticky droplets that the spider produces in a gland in its stomach. Only the very fine threads, called viscid threads, are sticky and designed to entrap insects that spiders eat.
The glue-coated viscid threads of a spider’s web are about a third of the diameter of a human hair. The spider webs silk threads are flexible, making it very difficult for the prey insect to get leverage to free itself.
The more the insect struggles, the more it invariably gets tangled in the web. Spiders know which strands of the web are coated with the glue so avoid stepping on them to avoid being trapped by the spider’s web.
Can Spiders Run Out Of Web
Spiders secrete the silk from which spider webs are made from their spinneret. The spider produces its silk which is very high in protein. A spider can run out of web if the spider is in poor condition.
Not having fed for a long time, injured or very old, would drain its bodily reserves. Under normal conditions, the spider can produce sufficient silk from reserves built up in its body to complete the web that the spider is building.
In the instance where the spider has just completed the new web, and the web is destroyed, the spider may not have sufficient silk immediately available to complete a brand new web.
Conclusion
Spiders are unique in that they can produce silk threads to build webs to catch food. The spinneret, an organ in the spider’s abdomen, can produce multiple different types of thread on demand, depending on the thread required for each part of the web built by the spider.
The spider draws a thread out from the spinneret much like a dragline, as it makes its way from point to while building the web. Each thread is meticulously attached to a specific point on the vertical and horizontal lines until the web is fully completed.
