Is fear of insects (and arachnids) a biological or learned response?

I’ve sometimes wondered if the all-too-common reaction to the presence of insects and spiders - revulsion, disgust and fear - is the product of the attitudes of Western culture, or if it is something ingrained in our biology that we are naturally predisposed to?

If it is biological, then what purpose does it serve? Why would an overwhelming amount of people react in such a manner to a creature much smaller than themselves, but a far fewer number of people react in the same way to a large predator, like a tiger?

On a personal level, I don’t have a fear of insects or spiders, although I dislike webbing produced by some spiders and caterpillars. My father has no fear of insects or spiders, but my mother has a fear of both.

My opinion, and I’m not sure we can get anything more definitive than that, is that it is learned. I base that on anecdotal experience.

One example is from my medical entomology professor discussing how his daughter had no fear at all of arthropods as a very young girl, but had developed a “girlish” revulsion of them when she was slightly older. This story was ever so slightly amusing in that he was telling us this as he was showing us slides of the increasingly blistered hand she got from grabbing a meloid beetle at a young age :p.

Another is myself. I never had a fear of insects exactly, but I did have a slight aversion to touching/being touched by them by the time I was in my teens. An “icky” reaction if you will. Which I found faintly ridiculous, as I remember having no such aversion when I was younger. So as a sophmore in college I deliberately took a class in general entomology to break me of the habit. It worked - within days really.

Finally I’ve noticed in experiences with my nieces and nephew, as well as other younger kids in appropriate settings like the insect zoo in San Francisco or the Lawrence Hall of Science, that the younger they are, the less fear they seem to show. That’s pretty much the opposite of what I’d expect if the aversion were biological.

But you know what they say about anecdotes…

Here’s an article that discusses this briefly:

I dunno about the notion that because some behaviours emerge at a later age, they are not rooted in biology. Many behavious obviously rooted in biology are in fact age-specific - most obviously, sexual urges, which, though present before puberty, are more strikingly manifest after.

My own experience of young children (at least, anecdotally, my own) is that they are more or less fearless of anything - something that makes me, the parent, fear. A two year old boy seems to look for inventive ways to harm himself …

Thus, it could be that young children do not fear, because (evolutionarily speaking) their parents are around to fear on their behalf. As they age, certain fears become more manifest. As to whether these fears are inherent or learned I can’t say, though the widespread nature of fears like fear of spiders makes me suspect that there may be an inherent basis for 'em.

I wonder whether the aversion to insects and arachnids is learned at the same time as our aversion to rotting things. Many insects and arachnids (is there a common term for both, other than “bugs”?) are associated with the rotting process, and perhaps our emotional reactions to rot just carry over.

I’m thinking of my reaction to maggots in the composter, but also our reaction to disease, which can be considered the rotting process within our own bodies. And of course there’s good physical reasons to avoid rot as well: rotted food is bad for us

I think it’s innate, or at least has some innate component. I’ve seen several cats meeting their first snake, and they’re always terrified of it, whereas they’re not generally terrified of their first ball. Seems to me all us more complicated mammals would benefit by having evolved innate fears.

I could see an aversion to insects possibly being beneficial. There are insect-borne diseases, like malaria, that kill a lot of people. If someone who was averse to insects was less likely (even slightly less likely) to get those diseases, it could be beneficial. More humans have died of malaria and other insect-borne diseases than of attacks by any large predators, AFAIK.

Just an idea but maybe it would be useful to separate the fear of spiders from the fear of insects. The fear of six-legged bugs has never seemed universal or anything like it to me. I played with insects as a kid and I suspect many others have as well. No fear at all. Heck, I’ve eaten the things on several occasions.

Spiders are a different thing. The fear of spiders seems much more common and I could see a fear of spiders making sense from an evolutionary aspect as well as they can be fairly venomous.



I’m not afraid of spiders. That would seem to preclude a biological reason for being afraid of spiders. Unless I’m some sort of genetic freak. Furthermore I have no aversion to ants, beetles, wasps, or most other insects other than avoiding potential bites or stings. I admit to being revolted by maggots and roaches though but that’s probably because I view them as inherently filthy. Never mind that beetles can be filthy and I’ve seen ants stripping down a carcass before I still don’t associate them with filth like I do roaches and maggots.


Keep in mind that in some other cultures, particularly primitive tribal societies, far from being grossed out by “bugs”, people eat them. The reaction of a hunter-gatherer to a grub is less likely to be “yuck” and more likely to be “yum”.

(Before this is whisked to IMHO)

I am convinced that fear of spiders and “creepy bugs” is a learned behavior. If a child were to grow up in an environment where no adult ever gasped or showed any sign of fear or revulsion to spiders, etc., I’m convinced the child would not have any fear or revulsion.

I do think that there is a natural (inherited) fear of things that are larger than yourself (bears, rhinos, etc.). But I don’t feel there is any inherited fear of things much smaller.

So one learns which things are to be feared by how adults (or pretty much anyone older) reacts to them. Ladybugs and butterflys are learned to be “cute” and harmless. Whereas spiders are learned to (all) be dangerous and revolting.

I try to make a point of reacting counter to most adults when seeing the “creepy things” with kids 1) because they are not creepy to me, and 2) to present the other side of the story. But it is an uphill battle.

What is sad is that these ingrained fears tend to prevent most people from learning the real truth about things. Fear is a great “inhibitor” - that you need to be afraid of something (or whole types of somethings) is all you need to know. This explains most people’s lack of understanding about things like sharks (most species are not dangerous), snakes (ditto), spiders (ditto), etc. - the list is long.

I used to know a guy who worked in the education department at the zoo, primarily with reptiles. He said it’s so sad to see how the little kids, boys and girls alike, are so excited to see the animal - they want to touch it, they’re interested in it, etc., and then when they’re older it’s all “eeek” and “ew” and “slimy!” Particularly girls. Obviously as an educator he wants to find the point at which they stop being interested and positive towards the animal and stop it!

Both my parents raised me this way, to extremes. Each would capture snakes, lizards, insects, etc and demonstrate to their daughters that respect is necessary; fear is not.

I’m a girly girl, and afraid of nothing. Of course, I am not allergic to bees, and stings just make me mad rather than cause me emotional or physical distress, so that may also be a factor in my lack of fear. While hiking, gardening, and landscaping I have been bitten and stung by everything from sweat bees to Northern water snakes (hateful bastards) and I suffer nothing but an apparent lack of instinctive self-preservation.

Ladybugs are one of the examples I was going to use, along with fireflies. If it were something inborn, it probably wouldn’t distinguish between those and any other sort of beetle (yes, both ladybugs and fireflies are beetles… There’s a lot of those critters).

For another annecdotal data point, my mom encourages spiders in the house (since they keep the numbers down of other, less desireable, arthropods), and neither my sister nor I has any sort of aversion to them. Of course, that could also be argued that we inherited a no-fear-of-spiders gene from her.