Spiders: Fiction Vs. Fact

Brown Recluse: Public Domain, Alex Wild

FICTION: Brown recluse bites are common everywhere in North America.

This is a deeply entrenched misconception held not only by the general public but also by many in the medical community.

FACT: Brown recluses are blamed for causing skin lesions throughout North America, including Alaska and Canada, but they are almost solely restricted to an area from southeastern Nebraska to Texas to southwestern Ohio and northwestern Georgia. Almost all diagnosed brown recluse bites outside of this area are caused by other conditions such as bacterial infections, cancers, burns, Lyme disease, adverse reaction to medication and lymphoproliferative diseases, to name a few.

All images AdobeStock except where noted.

FICTION: Daddy long legs are among the most toxic spiders in the world but their fangs are too short to bite.

This urban legend is very well established in many English-speaking countries, including Australia.

Fact: First, we need to know which group of arachnids are being referenced. There are daddy long legs (also known as granddaddy long legs), which are not spiders. They are in the arachnid group called Opiliones. They have one major body part with eight long, spindly legs and do not make webs. The opilionid arachnids don’t have fangs or venom. They do have little pincer-like mouthparts for tearing apart vegetation or dead insects. They can give a little nip but they do not “bite” as we typically envision.

In contrast, daddy long leg spiders are in the arachnid group called Araneae; they have two major body parts with legs attached to the front body part and usually are found hanging upside down in webs. These spiders do indeed have short fangs and they are capable of biting although bites are almost unheard of; they prefer to scurry away. On the rare occasion of a bite, the effects are minimal as their venom is not very toxic to humans.

FICTION: Spiders can enter a home from the bathtub or sink drain.

People see a spider trying to crawl up the slick walls of a bathtub or sink and assume the spider must have come up from the drain.

FACT: There is a water trap in sinks so a spider cannot swim through water to enter a home. What is really happening is a spider falls into the sink or tub from the wall or ceiling and can’t climb out.

FICTION: You eat eight spiders in your sleep over a lifetime.

Here’s another doozy. Just how would someone collect this data? Have a scientist with a clipboard and night-vision goggles sit next to your bed for eight hours for nights on end watching for invading spiders once every few years? What agency would fund such a study?

FACT: As best that can be determined, this was a myth started in a magazine by someone who allegedly wrote an article regarding statements that people would believe if you put it in print. However, this might be a hoax within a hoax. When trying to track down the origin of this article, apparently neither the magazine or the alleged author existed.

FICTION: Black widow females always kill the male after mating.

Articles in the early 20th century reported sensationalistic stories about black widows which, at the time, were only just being accepted as being dangerous to humans.

FACT: For North American black widows, this myth was caused by tossing males into jars with females where the male couldn’t escape and was found dead the next day after mating. In reality, they prefer to escape in order to mate more times (duh). However, in some species, such as the Australian red back widow and the brown widow, the male offers his body to the female in ritualistic sacrifice after mating. If she is well fed, she may reject the offer.

FICTION: Brown recluses bite to liquify your skin to feed their babies.

Brown recluse: © James O. Howell, Bugwood.org

This outrageous bit of lunacy was promoted by a well-respected and influential scientist who obviously had no experience with spiders.

FACT: No spider uses humans as a host for any purpose. This myth can be dispatched on several biological bases.

First, it takes a brown recluse about six hours to construct an egg sac, which is usually hidden in a tight crevice. They would never make an egg sac on a living creature. Second, it takes about a month for brown recluse eggs to hatch and babies to emerge from the egg sac. If a human could go a month without finding or destroying an egg sac that is attached to skin just by normal daily hygienic behavior, then that person has deeper problems than brown recluses. Lastly, a brown recluse mom sits on top of the egg sac to protect it from parasites or other threats.

Can you envision someone walking around harboring a brown recluse and its sac for a month without discovering or inadvertently crushing both?

FICTION: Watch out for butt-biting spiders in airplane toilets.

In 1999, a hoax was started about a South American spider being found in airplane toilets with the spider spreading around the Chicago area. The butt-biting blush spider, Arachneus gluteus, killed several people, was highly toxic so you better forward the email on to friends and loved ones to warn them. Many people did.

FACT: I actually got involved in debunking this one (Vetter and Visscher, 2000). I erected a website pointing out the many incorrect bits of information in the hoax. Within a week, the hoax writer contacted me. He said he purposely wrote the hoax as an experiment to show that people don’t question outrageous misinformation they receive via email and that they just robotically forward it on. The hoax writer stated that he purposely put in all kinds of bogus information such that if the recipient had checked any one of the “facts” in the hoax, it should generate a red flag. Years later, the hoax was resuscitated by someone else by moving the incident to Florida with the writer using actual information such as a valid, harmless jumping spider species from Asia and a nationally known restaurant.

FICTION: Spiders in your beehive hairdo will kill you.

This is an older one that was prevalent during the 1950s where young women wore a beehive hairdo (i.e., hair that was arranged in a high tower from the scalp similar to Marge Simpson’s ’do). Lots of hair spray was used to petrify the hair in place. Because it was difficult to maintain, women didn’t shampoo their hair that often. Then a black widow would move in and lay an egg sac. Eventually either the adult spider or the hatched babies would bite the woman’s scalp, causing death. As fashion evolved, in the 1980s, the myth was re-worked for dreadlocks.

FACT: There is no truth to this myth whatsoever and is considered a classic urban legend. No one can ever verify an actual person who suffered a hairdo-related death.

FICTION: Tarantula babies will explode from a cactus brought inside.

Reports have been passed around about a person who bought a cactus from a garden shop, took it home and a tarantula egg sac hatched out, releasing hundreds of babies onto the property or in the home.

FACT: Tarantulas make their homes in the ground by digging a burrow into the soil. According to an expert on tarantulas and related spiders, they never would take up residence in a living, internally wet cactus.