A spider has eight legs and two body parts. An insect has three body parts. A spider is not an insect. Spiders are arachnids. Most spiders have eight eyes, though some have fewer.
Every kind of spider makes silk. Spiders make silk with spinnerets. Spider silk is very light, but it is also extremely strong and flexible. A spider web has sticky threads and nonstick threads. The spider knows which threads are safe to walk on.
Many spiders catch flies and other insects in their webs. An orb web has radial threads that make the frame and a spiral thread that catches prey. Orb-weaving spiders often eat their old silk and reuse it.
Not every spider builds a web. Some hunt for prey or wait for it. Wolf spiders are hunting spiders, and they do not build webs to catch prey. A mother wolf spider carries her egg sac under her body. When her spiderlings hatch, she carries them on her back.
Most spiders eat insects. After catching an insect, a spider wraps it in silk. Spiders use venom to paralyze the small animals they catch. Spiders cannot chew solid food, so they put digestive fluids into their prey. A spider's mouth is shaped like a tiny drinking straw and sucks rather than chews.
Jumping spiders hunt in the daytime and have very good eyesight. They can see more colors than people can.
Young spiders can float on the wind by releasing a long silk thread.
If a spider loses a leg, it can grow a new one as it molts.
Many animals eat spiders, including birds.
Most spiders are harmless to people. Spiders very rarely bite people, and they do not seek people out to bite them. Do not touch a wild spider. If you see one, tell a grown-up.
Words to know
- arachnids: spider group
- spinnerets: silk makers
- venom: paralyzing fluid
- digestive: breaking down food
The short version
Spiders are arachnids, not insects. A spider has eight legs and two body parts. Every spider makes silk, but not every spider builds a web. Some hunt for prey or wait for it. Most spiders eat insects, and most spiders are harmless to people.
Quick facts
- A spider has eight legs and two body parts.
- Every kind of spider makes silk with spinnerets.
- Not every spider builds a web.
- Most spiders have eight eyes, though some have fewer.
Is a spider an insect?
No. A spider is not an insect. Spiders are arachnids. A spider has eight legs and two body parts, and an insect has three body parts.
Do all spiders build webs?
No. Every kind of spider makes silk, but not every spider builds a web. Some hunt for prey or wait for it. Wolf spiders are hunting spiders, and they do not build webs to catch prey.
