Studies have examined this issue with empirical rigor and found that, indeed, some aspects of who we are now can be predicted from photos taken earlier in life.

Given the love affair the United States has with marriage and divorce, my lab recently examined whether marital stability, or lack thereof, can be predicted from a photograph—a snippet of time. In a sample of more than 600 people, we coded the degree to which people smiled in their college yearbook photos by examining how much two muscles in the face contracted: the oribularis oculi and the zygomatic major muscles. In a nutshell, those who smiled least in their photos were five times more likely to divorce compared with those who smiled the most.

We followed this study with another in which we collected a variety of types of photos (birthday, portrait, etc.) that were taken earlier in life (the average age was 10). This study replicated the first; people who divorced later in life smiled less compared with those who stayed married.

Researchers have examined other variables associated with photos taken in early adulthood. In 2001, LeeAnne Harker and Dacher Keltner coded the degree to which women smiled in their senior college yearbook photos and found several interesting links. Compared with women who smiled least, those who smiled most were more likely to be married by their late 20s, reported happier marriages, and had a greater sense of well-being throughout their adult lives.

The findings indicate that, on average, our visage in early life portends something about our future. No doubt, there are likely cultural differences, and one would be hard-pressed to make an accurate prediction about an individual from a photograph; we found, for example, plenty of people who smiled little in their photos but remained married.

However, the pattern of findings seems to hold for most, and there are dozens of explanations for the link between early smiling behavior and life outcomes. A large body of theoretical and empirical work indicates that our tendency to experience and display emotion is relatively stable over our lives. Smiling in childhood and early adulthood may reflect a more positive disposition, which may have consequences for our marriages, friendships, and well-being.

Several other explanations are possible. Perhaps people who smile in response to the directive from the photographer to smile are more obedient people in general. Obedience may be a trait that leads to longer-lasting marriages. Of course, our findings are correlational, so no inferences of causation can be drawn with confidence. The task remains for researchers to better understand how such a small sample of behavior in a person’s life can predict anything about our future selves.

Matt Hertenstein is a professor of psychology at DePauw University.