Phobias are fascinating. It makes sense that a person would avoid, or even fear, something, but for the response to be completely involuntary and irrational; that’s where it gets interesting. What evolutionary advantage might a certain phobia have given someone generations ago? Geoff Cole, at the University of Essex, tried to answer this question for a phobia he recently brought into the scientific literature himself: trypophobia, or a fear of holes. Specifically, this phobia is usually triggered by clusters of holes (that are nearly always harmless), such as shown in the lotus seed pod below.
About 16% of people in a study were found to be trypophobic. What exactly is it about such images that causes the response in people? To figure this out, Cole showed volunteers images known to trigger trypophobia as well as images of holes that were known not to cause a trypophobic response. He found a trend among the trypophobia-inducing ones; they had high contrast at midrange spatial frequencies. This narrowed it down a little, but the question still remained – what purpose did it serve to have such a strong response to these types of images?
Cole had the realization that poisonous animals may have something to do with it. He analyzed images of extremely poisonous animals – such as the blue-ringed octopus (Hapalochlaena lunulata) and the king cobra snake (Ophiophagus Hannah) – and found that they indeed shared features similar to the known trypophobic images. Consequently, the phobia may have come to be because it helped early people avoid dangerous animals. The response is quick, before the person has time to think about it, which works well for avoiding death by an extremely poisonous animal.
So while many phobias that people have can be hard for us to understand in our modern societies, they may likely have helped us survive to where we are today.
For further reading:
- Geoff G. Cole and Arnold J. Wilkins’ article “Fear of Holes” in Psychological Science
- Anna Mikulak’s article “Fear of Holes May Stem From Evolutionary Survival Response” in the Association for Psychological Science press release
- The Huffington Post’s article “Trypophobia, Fear of Holes, May Have Evolutionary Basis“
- ScienceDaily’s article “Common Phobia You Have Never Heard Of: Fear of Holes May Stem from Evolutionary Survival Response”