Spider-Man seems to have gotten his superpowers from jumping spiders. They’re strong, fast, agile, and almost supernaturally smart. They’re also good dancers and just too cute. But if you’re food or foe, they’re eight-eyed ninjas that target small bugs and other spiders. Scientists have named 5,800 kinds of jumping spiders. Jumpers can live just about everywhere, even on the slopes of Mount Everest! Let’s meet six jumpers that live right here in Missouri.
Get a look at those eyeballs. All eight of them. Jumping spiders have four pairs of eyes. Three smaller pairs appear like fixed running lights on either side of the two, large front-facing eyes. These are movable, just like yours. With their ability to see nearly all the way around themselves, jumping spiders are hard to sneak up on. They’re also really good at spotting prey.
Jumpers don’t have ears, but they can “hear” just fine, thanks to their sensitive body fuzz. Scientists have discovered that jumpers’ tiny hairs can pick up vibrations from 10 feet away.
This little black-and-white jumping spider is less than ¼ inch long, about the size of a sunflower kernel. Look for it in meadows, old fields, and prairies. The female’s abdomen may be more purple- than black-patterned.
“Dimorphic” (die-more-fik) means “having two forms.” In this case, the male can be either all black or all gray. Look for this small jumper (the female is about half an inch long) in bushes, small plants, wet areas, and possibly your house.
Studies show that jumpers can learn and remember colors. This helps them detect prey and navigate toward it, even if it’s hard to reach. Some jumpers are known to pluck the edge of a spiderweb to trick the web-builder into crawling within reach. Then the jumper jumps onto the prey spider, avoiding the sticky web.
Females don’t have the males’ white markings. Look for bronze jumpers this fall crawling on the sides of buildings. You may also find them gathering to overwinter under the bark of dead trees.
Bigger spiders like tarantulas have large, powerful legs to help them hustle after prey. But jumping spiders use the power of hydraulic pressure to propel themselves through the air. They squeeze the fluid in their bodies and quickly release it to create a sudden push, allowing them to jump as much as 50 times the length of their own bodies.
Since spiders often eat each other, jumping spider males signal their sweethearts that they’d rather not be on today’s menu. After all, jumper males are usually as much as one-third smaller than the females. They use flashy dance moves and rumbling rhythms to persuade their partners to accept their advances. If the female doesn’t like the male’s display, she eats him!
You might mistake this tiny jumper for an ant, which it closely resembles. Why is it called “hammerjawed”? Maybe because its face is so flat. Look for it on low-growing plants in open woods.
It may be hard to detect this jumper in its natural setting. It lives on tree trunks, and its gray, tan, and brown color pattern helps it blend into the tree bark.
October 10 is International Jumping Spider Day
If you’ve fallen in love with jumping spiders, jump on this chance to celebrate them. Jumper fans worldwide have set October 10 to show these special spiders how much they’re loved. How will you celebrate?