We’ve looked at predicting people from a distance: employing stereotypes and homogenizing outgroups. Moving a step closer to the self, consider an individual you have just met. What are you looking for in the first few minutes of interaction? Among other things, often first among them, is predictability.
A member of your tribe is highly predictable. If you share a taste in clothes and podcasts you can predict with high confidence how they’ll react in social situations, what their habits and motivations are, etc. That’s why small talk about last night’s episode of Game of Thrones isn’t a waste of time. It communicates: I am like you, you can model me well by looking at yourself, we can cooperate.
Second best is someone who fits well in a group stereotype, even if that’s not your ingroup. You may not befriend many middle-aged bearded men who speak a language you can’t recognize, but you feel comfortable getting in a taxi with one.
Now consider someone who looks like you, watches the same shows, and also eats spiders they catch around the house. Would you get in a taxi with them?
The opposite of predictability is creepiness. In the leading research paper on the nature of creepiness, the author describes it:
The perception of creepiness is a response to the ambiguity of threat. […] While they may not be overtly threatening, individuals who display unusual patterns of nonverbal behavior, odd emotional responses or highly distinctive physical characteristics are outside the norm, and by definition unpredictable.
Eating spiders by itself doesn’t make one dangerous, but it’s a signal that this person can’t be predicted well by pattern matching to stereotypes or by self-modeling (unless you’re an arachnophage yourself). We react to creepiness not with fear but with aversion. We dislike what we cannot predict.