Recent findings in a study conducted by UC Santa Barbara anthropology professor Michael Gurven call into question a long-standing theory about the universality of personality traits.
Otherwise known as the Five-Factor Model, the theory, which is often applied in the field of psychology, states that a series of broad personality traits are inherently universal among all humans. The idea, according to scholar Christopher Von Rueden, evolved from a series of personality questionnaires with results that tended to clump together. The traits, often referred to as the Big Five, include: openness, conscientiousness, extraversion, agreeableness, and neuroticism.
Gurven and his team, including Von Rueden, who’s a postdoctoral scholar in anthropology, sought to find out how the Five-Factor Model and personality variation applied to small scale societies. They interviewed 632 members of the Tsimane, an indigenous group that inhabits central Bolivia. The Tsimane live in communities of 30 to 500 people that are scattered between 90 villages.
Gurven and his team discovered that the Tsimane didn’t demonstrate Big Five personality traits. Instead, they found that the Tsimane exhibited traits of what they referred to as the Big Two: prosociality and industriousness, which may be unique to smaller, self-subsistent communities like the Tsimane. The findings appear in the current issue of the American Psychological Association’s Journal of Personality and Social Psychology.
“The Tsimane are attractive as a study population because their way of life is much more similar in many respects to the way humans have lived for the majority of their existence,” Von Rueden said in an email. “The industrialized societies in which we live are not the norm, and what we learn of personality, social behavior, or health in small-scale societies (how ecology shapes those things) can tell us a lot about human evolution,.”
Gurven’s interest in the Tsimane came from a larger health survey of the tribe. This project, which seeks to “understand the role of ecology and evolution in shaping human life history,” has been funded by the National Institutes of Health and the National Science Foundation.