In 2009, the journal Evolution and Human Behavior published a study that investigated whether people were afraid and disgusted by spiders and other potentially dangerous arthropods.
Arthropoda is a biological classification that accounts for almost 80% of all living species and includes animals such as insects, crustaceans, and arachnids.
Research has found that spiders are one of the most feared animals encountered by human beings, but whether such fear was present for other dangerous arthropods, such as bees and wasps, remained uncertain.
The study, which was conducted by Antje B.M. Gerdes, Gabriele Uhl, and Georg W. Alpers, compared the responses of seventy-six college students exposed to 60 pictures of various species of arthropods. The arthropod species shown to the participants included fifteen pictures of spiders, fifteen pictures of beetles, fifteen pictures of bees and wasps, and fifteen pictures of moths and butterflies.
Gerdes and her colleagues found that pictures of spiders were rated as being the most disgusting, fear evoking, and dangerous. Bees and wasps came in second place for dangerousness and fearfulness, but tied with the pictures of beetles for levels of disgust.
It was also found, not surprisingly, that female participants were more likely than male participants to be afraid of spiders, bees, wasps, and beetles.
But why do spiders evoke a special sense of fear and disgust, while other harmful arthropods, such as wasps, do not produce similar levels of fear and disgust?
Some psychologists have proposed that humans have a “biological preparedness” for spider phobia.
“This hypothesis is based on the fact that most spiders and many snakes are predatory animals and possess venom to immobilize their prey,” as Gerdes and her colleagues explain. “They are thus thought to have been potentially hazardous for our pretechnological ancestors.”
According to this explanation, those who are predisposed to being afraid of animals such as snakes and spiders are less likely to become victims of their dangerous venom, providing an evolutionary advantage over those without this predisposed fear.
As Gerdes and her colleagues note, if this explanation is correct, then the fear of insects such as bees and wasps should be at least equal, if not greater, than that of spiders.
“Compared with spider stings, bee and wasp stings are aggravated by the facts that humans encounter bees and wasps more often, encounters usually occur in swarms, and encounters often occur near food sources.”
The results of Gerdes and her colleagues study suggest that biological preparedness probably does not provide a complete explanation of social phobia, although it may play a part.
“Because our data clearly demonstrate that spiders are rated significantly higher in fear and danger and fundamentally differ in disgust ratings compared with other harmful arthropods, we conclude that responses to spiders to spiders are indeed special, but the existing explanations for spider fear are not yet well founded or rather insufficient. To which degree reactions towards spiders can be better explained by cultural transmission than by biological preparedness needs further investigation.”
Reference:
Gerdes, A.B.M., Uhl, G. & Alpers, G.W. (2009). Spiders are special: fear and disgust evoked by pictures of arthropods. Evolution and Human Behavior, Vol 30: 66-73.