My wife has long been familiar with my "limited gene pool theory," a concept that I bring up repeatedly. Spawned by my experience that many (if not most) humans have a close resemblance to others on the planet and by the knowledge that there must be a limited number of genome combinations in the human population, the theory usually surfaces when we encounter someone who reminds us of an individual from our collective past.
This morning, while supervising my grandsons at a large playground in Columbia, evidence of the theory's validity was readily apparent. I saw my oldest daughter at age 3, one of my nieces and a boy who was a close friend in grade school. Of interest, the physical resemblance is often accompanied by behavior and mannerisms that reinforce the link, suggesting that our body features influence our activity and social interactions (or vice versa).
As someone who has often been mistaken for others, perhaps I am especially sensitive to such similarities. On the other hand, there is little doubt that our genetic heritage has a profound effect on every aspect of our lives, from physical traits to our behavioral, intellectual and emotional makeup. If nothing else, it's entertaining to recognize relatives, friends and past associates in a crowd of strangers.