If you’ve ever seen a new home being built, you know that the workers use wooden boards to frame the house. Instead of boards, spiders produce silk threads to build their webs.

The silk is produced in silk glands with the help of the spider’s spinnerets. Spinnerets are special organs that allow the spider to decide what type of thread it needs for the web.

The silk threads can be thick or thin, dry or sticky, beaded or smooth. The threads a spider uses to construct its web begin as liquid, but they dry quickly in the air.

Spider webs are quite elaborate. How do spiders learn to make such complex geometrical patterns? Making webs is instinctive for spiders, which means nobody has to teach them how to do it. They are born knowing how.

When a spider begins a web, it releases a silk thread. It anchors the thread to some object — a branch, a corner of a room, a doorframe — wherever it builds its web.

As the spider moves back and forth, it adds more threads, strengthening the web and creating a pattern. Lines that go from the center of the web outward are called “radial lines.” They support the web. Threads that go around and around the web are called “orb lines.”

So why do spiders spin webs? When you need food, you go to the grocery store. When a spider is hungry, it heads to the web.

The main reason spiders spin webs is to catch their dinner. When an insect, such as a fly, flies into a spider’s web, it gets stuck on the sticky threads.

When a spider catches prey in the sticky strands of its web, it approaches the trapped insect and uses its fangs to inject venom. The venom either kills or paralyzes the prey, allowing the spider to enjoy its dinner in peace.

Not all spiders use webs for food, however. Some don’t build webs at all. Other spiders chase their prey. Some even make sticky nets, which they throw over their prey when it gets close enough.


17 Join the Discussion

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  1. We solved your wonder using a book on spiders. Spiders spin webs to help them catch their food or prey. We wondered if all spiders made webs. We found out that they not all of them do. Wolf spiders, tarantulas, jumping spiders, fishing spiders and lynx spiders do not spin webs.

    • WOW! Thanks for adding some AWESOME facts to this Wonder of the Day® about spider webs, Mrs. Nuse’s K Library Class! We LOVE it when our Wonder Friends share what they know with us! We like learning new things, too! :-)

    • not only are they called spider webs there called cob webs and when u get bit by a spider at first it satrts to itch then form redness , and if its a really bad poisnis spider that bit u it will start to spread if that happends go to er no matter if it spreads or not hall butt to the ER or soem kind of emergney

      • Thanks for sharing additional information with everyone, Maliyah! We’re so glad you’re WONDERing with us today! :)

  2. Every evening for the past week, a spider about the size of a quarter spins a large web on our front porch. By the morning it is gone. Why doesn’t she leave the web there in the daytime?

    • WOW, how cool that you’re able to experience that spider’s home every evening! It’s truly a work of art!!

      We Wonder if you have explored the life of different spider species. Some are known to weave their webs in the evening, but to protect themselves from predators, they take down their web after they’ve caught their prey. Everything is usually gone before dawn!

      Take a look at this video, which captures a spider deconstructing its own web: http://youtu.be/PkILnPfs6Ck

      Thank you for WONDERing with us! :)

  3. Ya I love spiders they’re awesome do you like spiders? So I want more spider facts soon so I can read about them so what’s your name? My name is Cassie.

  4. We did research on spiders and learned this: Spiders make silk in their tummies. We can’t make silk. Spiders make webs to catch their dinner, which can be flies and bugs and insects. Not all spiders spin webs. Some spiders spit thread and some look like flowers and hide and some run with their long legs.

    • We’re so glad you shared your research about spiders with us, Mrs. Nuse’s 1st grade class! Now we’re WONDERing what these flower-like spiders look like! They sound pretty neat! We think the students of Mrs. Nuse’s class ROCK! Thanks for stopping by Wonderopolis! :)

    • That’s right, Morgan! They’re both classified in the order of Araneae. Thanks for sharing this extra piece of information with all of us! :)

  5. Hi. WOW, we loved finding out information about spiders on this website and we learnt so much from this article. We are just WONDERING why some spiders take down and put back up their webs everyday????:):) thanks so much,
    OPS students.

    • Thanks for WONDERing with us, Alice, Kaiawa, Ellie and T’leya! You’ve asked a great question! Can you think of some reasons why a spider might want to take down his web and rebuild? :)

  6. Hi I want to be an entomologist when I am older so this page is awesome and pretty accurate to my research! Keep up the great work

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Have you ever wondered…

  • Why do spiders spin webs?
  • What are spider webs made of?
  • How do spiders learn how to spin webs?

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