Arachnids have four pairs of jointed legs, two body sections and simple eyes. Arachnids are aggressive predators and include spiders, scorpions, mites and ticks.
Spiders have been on Earth a whole lot longer than we have — 380 million years, to be precise — and number more than 38,000 separate species worldwide. See 10 of the most beautiful and scary of these arachnids.
Arachnids include spiders, mites, ticks, harvestmen, chiggers and scorpions. Learn more by viewing these arachnid pictures.
Spider silk is five times stronger than steel and twice as strong as bullet-proof Kevlar. What exactly is spider silk, what is it made of and why is it so strong? Find out the answers to these questions and learn other facts about spider silk.
Scorpions have been around for 450 million years. But the species hasn't been sustained by a healthy, vibrant diet: This opportunistic eater would rather wait for food to come to it than go out hunting for it. So how many meals does that amount to?
If looks could kill, bristly tarantulas would be the spiders to watch out for. But violins and hourglasses are far more cause for concern.
Studies have shown that you're never more than ten feet away from a spider is and one estimate puts you as close as three feet. Check out some more spider facts.
If you have ever been out in the woods or an open field in spring, summer or fall, you may have gotten chiggers around your waistband or on your ankles. They leave red, itchy bumps on your skin. Learn more about these arachnids.
Chiggers are tiny arachnids that are known for delivering bites that itch intensely. Find out how chiggers work and learn about the chigger reproduction cycle.
Ticks are parasites that feed on the blood of their hosts -- human or otherwise -- and are known for carrying diseases. Learn all about ticks, including how to remove them.
Love 'em or hate 'em, you've got to admit that spiders are some pretty impressive animals. Movies like "Arachnophobia", "Spider-Man" and "Eight Legged Freaks" even spin their stories around spiders. Check out the real-life web-slinging, wall-crawling, venom-injecting inspiration.