"If we choose healthy partners because our visual system picks them out due to perceptual fluency, then we may still have an evolved mechanism to prefer averageness." I've never heard it put that way, but in dealing with clients, I have encountered a human predilection for averageness. Lamentably, most people prefer: safe, boring, tame, lukewarm, ho-hum, stale, trite. Guess the most popular variety of bagel? Plain.