Currently, more than 46,000 spider species stretch their eight legs in habitats across the world, in every country and continent except Antarctica. And those are only the ones scientists have been able to find and name so far—many more are likely still out there, lurking under leaves and rocks and, for Halloween’s sake, perhaps under a bed or two.
Although some people find these creatures terrifying—a spooky symbol of haunted houses and Halloween frights—we owe a lot to our arachnid friends. Not only have they been around for about 350 million years (trumping our puny 200,000-year modern human existence), spiders make it possible for us to eat and live a more comfortable life.
“If spiders disappeared, we would face famine,” Norman Platnick, a spider expert at New York’s American Museum of Natural History, told the Washington Post in 2014. “Spiders are primary controllers of insects. Without spiders, all of our crops would be consumed by those pests.”
For that matter, so would we. Because spiders munch on insects, they save us from bites.
“Without spiders’ existence and abundance on the planet, life on earth would probably be a less hospitable place for people because the biting flies and mosquitoes of the world would be so populous,” Cat Urban, manager of the invertebrate live animal programs at the Natural History Museum of Los Angeles County, which hosted a Spider Pavilion for visitors in 2018, told Smithsonian.com.
This year, museum-goers can face their fears further north at the Royal Ontario Museum in Toronto. Through January 6, 2019, over 400 live and preserved arachnids will be on display in the museum's Spiders: Fear & Fascination exhibition. Hands-on activities, live venom milking demonstrations, augmented reality experiences and a recreated spider cave bring visitors face-to-face with these fascinating and misunderstood creatures. The exhibit features two of the world's largest spiders, the goliath birdeater and the Brazilian wandering spider.
If you want to see these and other eight-legged giants in the wild, here are a few places to see the world's biggest:
Giant Huntsman – Heteropoda maxima (Laos)
This type of spider was discovered in Laos in 2001, hiding in a cave. Measuring by leg span, it’s the biggest in the world—the creepy crawlers can reach up to a foot wide. They’re crazy fast, can climb up smooth surfaces and walk sideways. Fortunately for arachnophobes, all huntsman spider species are as scared of us as we might be of them. They’ll run away fast once you see them, and they don’t like to bite (though they won’t kill you if they do, just cause some local swelling). The giant huntsman lives in caves in Laos and has only been seen on rare occassion. Other species of huntsman spiders, that average only about five inches in leg span, are common in Australia and Asia.
Goliath Birdeater Tarantula – Theraphosa blondi (South America)
Based on mass, this is the largest spider in the world (leg-span measurements make it second to the giant huntsman). They’re so big that in 2014, an entomologist wandering through the rainforest in Guyana found one that was as big as a puppy and weighed just as much. The name may just be a clever note on its size—it’s debated whether the spider actually eats birds. Mostly the spider dines on crickets, beetles and occasionally small mammals and frogs. In any case, it has fangs almost an inch long (although its bite is considered no worse than a wasp's sting) and is covered in tiny prickly hairs that it shoots out at whoever is bugging it. But the most distinctive thing about it is the sound it makes: it hisses. In order to shoot out the teeny hair, it has to rub its legs against its abdomen, creating a hissing sound.
The goliath birdeater can be found in the rainforests of northern South America, including Venezuela, northern Brazil, Guyana, French Guiana and Suriname, and at the Amazonia exhibit at the Smithsonian National Zoo.
Brazilian Salmon Pink Birdeater – Lasiodora parahybana (Brazil)
Just like its friend the goliath, this tarantula is really, really big. Its legs span up to 11 inches, and it grows six of those inches in just its first year of life. The spider is endemic to the Atlantic forest region of Brazil and can be seen wandering the forest floor at night.
The spider gets its name from coloring: pink hairs stick out in patches from the mouth, abdomen and legs. Plus, they really do eat birds. Small ones. Sometimes. Otherwise, they eat bugs, lizards, frogs and mice. But before dining, they spit digestive fluid onto their prey, so it’s partially digested before they dig in.
Sri Lankan Tarantula – Poecilotheria rajaei (northern Sri Lanka)
Ever wondered what a spider as big as your face looks like? This is it. Its leg-span is about eight inches. Scientists discovered it hanging around in trees and an old hospital in Sri Lanka in 2013. The spider’s coloring is unique—it has a pinkish band around the abdomen and yellow and gray geometric patterns on its legs. The name is unique as well; it was named after a police officer that helped scientists navigate the jungle to find the spider following the first sighting.
Brazilian Wandering – Phoneutria fera (South and Central America)
There are eight different species of Phoneutria, which means "murderess" in Greek, but the P. fera is generally the largest. Though only about half the length of the giant huntsman, this spider is no shrimp, sporting legs that can span up to six inches. P. fera is found in the Brazilian rainforests and urban areas of Brazil and northern South America. The spider gets its English name from wandering the jungle floor at night, rather than maintaining a lair or spinning a web. During the day, it likes to hide in termite mounds, under leaves and, in urban areas, in piles of clothes and shoes.
Brazilian wandering spiders are also among the most venomous spiders in the world, and fairly aggressive, so don't get too close. The venom has a chemical compound called PhTx3 that can lead to sever pain, inflammation, paralysis and breathing problems. Luckily, an effective antivenom exists, and the spider displays a distinct warning signal before it bites: it raises its two front legs and sways back and forth. The venom is also considered potentially medically valuable and is being studied for erectile dysfunction treatments.
Orb Weavers – Nephila maculata (southeast Asia), Nephila clavipes (U.S.), Nephila komaci (Africa)
These are among the largest orb weaver spiders in the world. According to Urban, their webs can be as big as eight feet across, and the spiders themselves measure about the size of a large hand’s palm. Orb weavers are common garden spiders—you’ll know them by the spiral-shaped web, large rounded abdomens and long legs. They may look pretty intimidating, but don’t worry; they just want to dine on mosquitoes and other bugs. The orb weavers are also a classic example of extreme sexual size dimorphism, with females growing three to five times the size of the males.
The largest known orb weaver, Nephila komaci, was discovered in 2009 in Madagascar. Females of this rare spider species can grow up to four to five inches in leg span.