In Search of a Look-Alike: Research Findings and Expectations |
Looking like someone does not mean you behave the same way.
Research on unrelated look-alikes tells us that personality has a genetic basis.
Twin studies offer insights into possible human reproductive cloning.
I became intrigued with look-alikes when one of my students told me about a website featuring photographs of people who look alike but are biologically unrelated to one another. It was created and is maintained by Canadian photographer Francois Brunelle. Ironically, Brunelle titled his work the “I’m Not a Look-Alike Project.”
My interest in these curious pairs of people comes from my research with twins. Twin studies show that genetic differences among people explain about 50% of the personality differences between them. This finding is consistent with an important result of a personality analysis done by the Minnesota Study of Twins Reared Apart (MISTRA), a project with which I was associated between 1982-1991. The MISTRA researchers found that the personalities of identical twins reared apart are as similar as the personalities of identical twins reared together. This shows that if we resemble our family members, it is because of our shared genes, not our shared environments.
A challenge raised against reared-together twin studies is that people treat identical twins the same way based on their appearance—and that this treatment, not their genes, explains their behavioral resemblance. I realized that I could test this idea using unrelated look-alikes. Two outcomes were possible: (1) Look-alikes would be as similar as identical twins, supporting the view that treatment largely shapes personality, or (2) look-alikes’ personalities would be different, supporting the idea that people........