As someone who has been involved in academia in some fashion for over ten years, here are my observations (note: this is <i>heavy</i> on subjectivity):<p>1. Those involved academically or professionally with some form of STEM, seem to be, on average, less physically attractive than the average population. If this is true, we can say that there is an (loosely) inverse relationship between physical attractiveness and intelligence.<p>2. People who have hyper-lower confidence in their attractiveness tend to have profile pictures of things other than themselves (anime, The Joker, wolves, flowers, etc.). If this is true, then there is a positive correlation between physical attractiveness and propensity to use a non-facial PFP.<p>3. Therefore, if 1 and 2 are true, then it follows that intelligence is roughly positively correlated with having an anime PFP.