Why do spiders seem significantly more scary than other small insects?


We are bigger. Why are they more scary than say an ant or a fly?


It’s *probably* an evolutionary advantage passed on from our early primate ancestors. Studies have demonstrated that we recognize spiders and spider-like shapes faster than other animals. Sometimes this happens even when we’re not consciously aware of it: our heart-rates will briefly spike after seeing an image of a spider, even if the image isn’t on the screen long enough for us to consciously recognize it. This does not happen with other animals (except maybe snakes? I can’t recall exactly. Snakes get some special treatment in our brains, too).

Unlike other groups of insects, arachnids, and bugs in general, spiders are *almost* universally venomous. There is a single family of spiders that do not have venom. While most spiders are not lethal, they are (almost) all at least universally painful. In the wild, any injury can lead to death from infection or being just a tad too slow to escape a predator.

Many of our primate cousins are insectivores, and our ancestors probably included some as well. Being able to recognize a harmless tasty snack bug versus a painful, potentially deadly spider is an important skill. One that is, apparently, baked into some deep recesses of our brains.