It’s time to break down some popular myths surrounding spiders!
Myth: “The daddy long leg is the most venomous spider in the world, but its fangs are too small to bite you.”
Let’s start with one of my favorite spider myths: the myth of the daddy long leg. I still hear this one when spiders come up, and I’m sure you’ve heard it, too.
First, the daddy long-leg is not a spider. They belong to a group of arachnids called harvestmen. Harvestmen are non-venomous, and don’t even have fangs. Their mouth parts are similar to a scorpion, with small claw-like chelicerae for tearing prey into manageable sizes. So no, they can’t bite you, and even if they could, they have no venom to speak of.
Myth: Only some spiders are poisonous.
In fact, no spiders are poisonous! But all spiders (except about 300 species in the family Uloboridae) are venomous.
There are two common misconceptions when it comes to venom. One, most people assume that venom and poison are the same thing. Two, they assume that only some spiders have venom.
For starters, the difference between venom and poison is important. Venomous animals use a fang or stinger to inject a toxin. Spiders, scorpions, bees, and wasps are all venomous arthropods. Poisonous plants and animals must be ingested for the toxin to work. They cannot bite or sting you. All spiders (except the aforesaid Uloboridae) use their fangs to inject venom into their prey. While they may use venom defensively, they prefer to conserve it for their dinner.
Some spiders have venom that is more potent than others. For example, consider the black widow. They are discreet, private predators who prefer to build webs in low traffic areas. Prey is not abundant near their webs, and they can go months between meals. As a result, they evolved potent venom to take down large prey.
Myth: We eat 8 spiders a year in our sleep.
This widespread urban legend doesn’t make sense when you break it down. Do you think a spider could climb down your throat without waking you up? There are few species that frequent human homes, and they tend to keep to themselves. Spiders will emerge to hunt at night but a massive, snoring mammal doesn’t offer much in the way of a productive hunting ground. Not to mention that most spiders have poor eyesight, and are extremely sensitive to vibrations.
The origin of this myth is largely a mystery, though some attribute it to an early 1990’s internet article. The writers claimed that most people would believe anything they read on the internet. They created the myth to prove it.
Myth: You’re always 3 feet from a spider.
This particular myth was unintentionally started by arachnologist Norman Platnick. Platnick was famous in spider circles and often referred to as the “Real Spider-Man.” In 1995, he wrote, “Wherever you sit as you read these lines, a spider is probably no more than a few yards away.” He was trying to convey that spiders are abundant, but folks took it literally and ran with it.
Myth: Spiders suck out the juices of their prey.
Actually, it’s grosser than that. Spiders have impossibly small mouths and are incapable of chewing their food. They have to liquefy their prey before they can swallow it. After they have subdued their prey using their venom, they regurgitate their digestive juices on or into their prey. The acid in the digestive fluid acts like you would expect it to: it digests the prey while the spider holds it in its fangs or keeps it wrapped in silk.
So it’s not just the “juices.” It’s the liquefied organs, tissue, muscle, hemolymph – all of it. All contained in one slurpable insect smoothie.
Myth: All spiders make webs
This myth is a close cousin to “only some spiders are poisonous.” It’s more of a misuse of language than anything. Not all spiders make webs, but all spiders DO produce silk. Some, like the charismatic orb weavers, build large, gorgeous webs in our gardens for capturing prey. Others, like tarantulas, use their silk to line their burrow. This allows them to detect vibrations of any prey that ventures close. Jumping spiders, whose unmatched eyesight makes them superior hunters, use their silk as a drag line. That way, they can return to the spot they jumped from when they are hunting prey.
Bonus myth! “Spiders use oils from their feet to prevent getting stuck in their own web.”
Spiders do not produce oils from their feet. They are capable of producing 7 different types of silk in their spinneret glands. Only some of that silk is sticky and used for prey capture. In reality, a spider is just clever enough to know where NOT to step.