8 Wildly Inaccurate Myths About Spiders (Plus the Truth)


You might know that spiders aren’t insects (they’re part of the Arachnida group, not the Insecta) but many other spider myths still persist. Chances are you’ve called any old web a “cobweb,” thought you were being nice by putting a spider outside instead of killing it, and made wild claims about how many spiders people swallow in their sleep each year. Read on to learn what’s real, what’s fake, and where the most persistent alternative spider facts got their start.


Webs are not houses—they are made to catch food. And not all spiders spin webs: some get their dinner by hiding inside flowers or hunting. Their silk production isn’t limited to webs, either: Spider silk comes in seven different varieties, from durable draglines and parachutes to the kind used to wrap up prey.


As far as scientists are concerned, “cobweb” isn’t just a synonym for a spider web. It’s a specific kind of web made by spiders from the Theridiidae family. Unlike the ritzy orb webs you might be more familiar with (like the one above), cobwebs are messy, three-dimensional webs that look more appropriate in a creepy house than a garden, though some Theridiidae species live outdoors.


Sorry, but they’re just not that into you. Spiders can tell the difference between a person and something they want to eat, and human sleeping sounds, like breathing and snoring, are pretty scary. Even if you roll directly onto a sheet covered in the critters, you’re more likely to make a mess than get hurt: spider fangs don’t stick up like dinosaur spikes. They’re on the other side, pointing down.


We all have that friend who makes a face when we kill a spider. They would never do that. They put spiders outside, usually using some stressful combination of a glass and a piece of paper. While there are outdoor spiders and indoor spiders, however, many species can’t survive in both environments. If you want to be nice, put the spider in your neighbor’s house.

Spiders don’t “come inside” in the fall, either. Those are just male spiders—who already live in your house—running around looking for a mate.


It depends on where you are. If you’re at a spider exhibit, sure. If you’re at the top of the Eiffel Tower, chances are pretty slim. This false fact is actually an arachnologist’s fault: In 1995, Norman Platnick started an article with “Wherever you sit as you read these lines, a spider is probably no more than a few yards away.”

There are over 40,000 different species of spider in the world, so it’s not totally bonkers to assume there’s one around you somewhere, but science doesn’t have a precise estimate for how close they are to you at any given time.


One of the most famous spider hoaxes involves an “allegedly deadly South American spider, Arachnius gluteus”—and that name should be enough to clue you in. While the original hoax, which began circulating in 1999, had obviously fictional elements—like a non-existent Chicago airport and a totally made-up scientific journal—recent versions sound more plausible. There still isn’t a venomous spider under your toilet seat, though—and if there were, it would be much more scared of you.


Spiders’ reputations precede them: They’ve been blamed for everything from regular old aggression to eating their mates and laying eggs in the cheeks of little girls. Contrary to popular belief, some spiders can be quite charming when the mood strikes. Both male fishing spiders and male nursery web spiders who treat their ladies to silk-wrapped snacks experience more reproductive success than spiders who show up empty-handed; a study led by Dr. Maria Albo found that nursery web males with gifts were allowed to mate nearly ten times longer than their unromantic counterparts.


We don’t swallow four spiders a year, eight spiders a year, 20 spiders in our lifetime, or any such number—unless, of course, you are a professional spider-swallower. “For a sleeping person to swallow even one live spider would involve so many highly unlikely circumstances,” Rob Crawford, Arachnid Curator at the University of Washington’s Burke Museum, writes.

According to, this myth was started in 1993 when a columnist for PC Professional included it on a list of false facts. She was trying to prove how quickly misinformation spread via email and, well, that is definitely true: It looks like a magazine called PC Professional never even existed.

All photos via iStock.

NUS Environmental Research Institute, Subnero
Researchers in Singapore Deploy Robot Swans to Test Water Quality
NUS Environmental Research Institute, Subnero
NUS Environmental Research Institute, Subnero

There's something peculiar about the new swans floating around reservoirs in Singapore. They drift across the water like normal birds, but upon closer inspection, onlookers will find they're not birds at all: They're cleverly disguised robots designed to test the quality of the city's water.

As Dezeen reports, the high-tech waterfowl, dubbed NUSwan (New Smart Water Assessment Network), are the work of researchers at the National University of Singapore [PDF]. The team invented the devices as a way to tackle the challenges of maintaining an urban water source. "Water bodies are exposed to varying sources of pollutants from urban run-offs and industries," they write in a statement. "Several methods and protocols in monitoring pollutants are already in place. However, the boundaries of extensive assessment for the water bodies are limited by labor intensive and resource exhaustive methods."

By building water assessment technology into a plastic swan, they're able to analyze the quality of the reservoirs cheaply and discreetly. Sensors on the robots' undersides measure factors like dissolved oxygen and chlorophyll levels. The swans wirelessly transmit whatever data they collect to the command center on land, and based on what they send, human pilots can remotely tweak the robots' performance in real time. The hope is that the simple, adaptable technology will allow researchers to take smarter samples and better understand the impact of the reservoir's micro-ecosystem on water quality.

Man placing robotic swan in water.
NUS Environmental Research Institute, Subnero

This isn't the first time humans have used robots disguised as animals as tools for studying nature. Check out this clip from the BBC series Spy in the Wild for an idea of just how realistic these robots can get.

[h/t Dezeen]

There May Be an Ancient Reason Why Your Dog Eats Poop

Dogs aren't known for their picky taste in food, but some pups go beyond the normal trash hunting and start rooting around in poop, whether it be their own or a friend's. Just why dogs exhibit this behavior is a scientific mystery. Only some dogs do it, and researchers aren't quite sure where the impulse comes from. But if your dog is a poop eater, it's nearly impossible to steer them away from their favorite feces.

A new study in the journal Veterinary Medicine and Science, spotted by The Washington Post, presents a new theory for what scientists call "canine conspecific coprophagy," or dogs eating dog poop.

In online surveys about domestic dogs' poop-eating habits completed by thousands of pet owners, the researchers found no link between eating poop and a dog's sex, house training, compulsive behavior, or the style of mothering they received as puppies. However, they did find one common link between the poop eaters. Most tended to eat only poop that was less than two days old. According to their data, 85 percent of poop-eaters only go for the fresh stuff.

That timeline is important because it tracks with the lifespan of parasites. And this led the researchers to the following hypothesis: that eating poop is a holdover behavior from domestic dogs' ancestors, who may have had a decent reason to tuck into their friends' poop.

Since their poop has a high chance of containing intestinal parasites, wolves poop far from their dens. But if a sick wolf doesn't quite make it out of the den in time, they might do their business too close to home. A healthier wolf might eat this poop, but the parasite eggs wouldn't have hatched within the first day or two of the feces being dropped. Thus, the healthy wolf would carry the risk of infection away from the den, depositing the eggs they had consumed away in their own, subsequent bowel movements at an appropriate distance before the eggs had the chance to hatch into larvae and transmit the parasite to the pack.

Domestic dogs may just be enacting this behavior instinctively—only for them, there isn't as much danger of them picking up a parasite at home. However, the theory isn't foolproof. The surveys also found that so-called "greedy eaters" were more likely to eat feces than dogs who aren't quite so intense about food. So yes, it could still be about a poop-loving palate.

But really, it's much more pleasant to think about the behavior as a parasite-protection measure than our best pals foraging for a delicious fecal snack. 

[h/t The Washington Post]


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