You don’t have to love ‘em, but there’s no denying that we’d all be a lot worse off without the ecological benefits spiders provide. Join us as we clear up some misconceptions—and revel in some wild facts—about these wonderful arachnids.
1. Spiders can be found nearly everywhere—even on Mount Everest.
It’s a myth that you’re never more than 3 feet from a spider, but they sure are abundant. Scientists recognize over 48,000 different species, distributed across every continent besides Antarctica. Spiders live in all sorts of habitats, from deserts to jungles to wetlands. They even live on some of the world's highest mountains. The tiny Himalayan jumping spider lives at elevations of up to almost 22,000 feet above sea level, and has been found on the slopes of Mount Everest. Meanwhile, the Andes Mountains are populated by high-climbing tarantulas. Seven new species were recently found there, including a skillful burrower that was seen at altitudes above 14,700 feet.
2. The world’s spiders consume millions of tons of insects each year.
According to one 2017 study, the average square meter of land contains roughly 131 spiders. Using relative body sizes and food habits, the study’s authors estimated that “the global spider community” eats a collective 400 to 800 million tons of food—including insects and small vertebrates—per year.
3. Not all spider webs are considered cobwebs.
A cobweb is a specific type of spider web that’s defined by its disheveled appearance. Some webs are well-organized, spiral-like structures made with ring after ring of concentric circles. By contrast, cobwebs don’t really follow any recognizable pattern, per se. They’re tangled, sprawling things made by the aptly named “cobweb spiders” of the Theridiidae family. (Black widows belong to said group.)
4. Some spiders turn their webs into slingshots …
Using its own body like a catapult to create tension between the lines in its web, the Peruvian triangle weaver spider launches itself towards hapless insects. After it springs forward, the arachnid accelerates like crazy. In the span of just one second, the critter’s speed can increase by the equivalent of 1700 miles per hour. During the process, the oscillating web enmeshes the victim, increasing the odds of a kill without requiring the spider to get too close to potentially dangerous prey.
5. … And some like to go ballooning.
A ballooning spider near B.K. Leach Memorial Conservation Area in Missouri. Andy Reago & Chrissy McClarren, Flickr // CC BY 2.0
Ballooning is a popular travel strategy among young spiderlings and small-bodied adults. The technique is simple: A wayward arachnid uses silk strands to catch the wind and ride its currents over vast distances. (Frequent fliers may also be taking advantage of earth’s electromagnetic fields [PDF].) In southeastern Australia, mass migrations of hang gliding spider babies are a common sight. Sometimes, it looks as though the sky is raining spiders.
6. The giant huntsman spider is the size of a dinner plate.
First discovered in Laos in 2001, the giant huntsman spider doesn’t build webs; instead, like other huntsman spider species, it actively tracks down the insects it dines upon. From leg tip to leg tip, the giant huntsman measures 12 inches across, giving it the longest leg span of any modern spider. So does that make it the world’s biggest spider overall? Well, that depends on what measurement you’re using. For all its leggy prowess, the giant huntsman is outweighed by the Goliath birdeater tarantula, a 6-ounce juggernaut thought to be the heaviest spider alive today. But while the tarantula is beefier, it’s got a slightly smaller leg span.
7. Male nursery web spiders trade gifts for sex.
Male nursery web spiders (Pisaura mirabilis) approach potential mates with dead insects “gift-wrapped” in silk. That wrapping material is loaded with male pheromones, but female spiders seem to be totally unphased by the amorous chemicals, according to a March 2018 study. Instead, they focus on the food itself. Approaching females empty-handed is a risky proposition: Males who fail to offer gifts are six times more likely to get eaten by their would-be mating partners.
8. “Sea spiders” aren't really spiders.
Not every so-called "spider" is an arachnid. Despite their common name, sea spiders aren’t considered true spiders; they belong to a different class called Pycnogonida. Found in every ocean, the spineless creatures suck up food through a hose-like apparatus and crawl around on eight to 12 segmented legs. The biggest species have incredible leg spans of over 28 inches. Just how they might relate to the spider family tree is unclear, though—because the delicate animals are rarely preserved as fossils, scientists aren't quite sure of their origins [PDF]. While some research suggests that they are chelicerates, belonging to the same subphylum as spiders and horseshoe crabs, others believe they may have evolved separately.
9. Indoor plumbing may have led to a decrease in black widow bites.
Black widows (genus Latrodectus) are among the world’s most feared invertebrates, with North America’s three resident species being especially notorious. Their neurotoxic venom can be fatal to humans, so be sure to give the spiders a wide berth. Yet, your chances of being bitten by one are fairly low. Most black widows prefer to hide rather than bite. And even when they do bite, the spiders sometimes withhold their venom, which is better spent on prey than humans.
During the 20th century, the number of reported black widow bites (as well as fatalities) in America significantly declined. We may in part have our changing bathroom habits to thank for that development. Outhouses are ideal spider shelters, but now that indoor plumbing is here to stay, you don’t see many backyard toilet shacks anymore. Experts think the decline of outhouses led to fewer encounters between widow spiders (including black widows and their relatives, brown widows) and people—and thus fewer bites. And though people do still occasionally get bitten, modern medical advancements have made fatalities very rare.
10. The longest-lived spider on record died at age 43.
For over four decades, scientists kept tabs on a wild trapdoor spider known simply as “Number Sixteen.” First sighted in 1974, the tiny female—less than an inch in width—defended a home burrow in Western Australia. Her death due to a wasp sting was announced in April, 2018. Prior to Number Sixteen, the oldest individual spider in recorded history was a Mexican tarantula that reached the age of 28.