US psychologists have disputed the long-held notion that a group of five personality traits or their variations are a universal feature of human psychology.

However, University of California Santa Barbara (UCSB) anthropologists have questioned the veracity of that five-factor model (FFM) of personality structure, bearing on indigenous populations.

Studying the Tsimane, an indigenous group in central Bolivia, Michael Gurven, professor of anthropology at UCSB, found they did not necessarily exhibit the FFM model, comprising openness, conscientiousness, extraversion, agreeableness, and neuroticism, according to the Journal of Personality and Social Psychology.

The Tsimane live in communities ranging from 30 to 500 people dispersed among approximately 90 villages.

Since the mid-20th century, they have come into greater contact with the modern world although fertility and mortality rates remain high, the study noted.

Previous research has found strong support for what experts refer to as the “Big Five” in more developed countries and across some cultures, according to an UCSB statement.

But Mr Gurven and his team, which includes Christopher Von Rueden, postdoctoral scholar in anthropology, discovered more evidence of a Tsimane “Big Two” — prosociality and industriousness.

These combine elements of the traditional Big Five and may represent unique aspects of highly social, subsistence societies.

“Similar to the conscientiousness portion of the Big Five, several traits that bundle together among the Tsimane included efficiency, perseverance, and thoroughness. These traits reflect the industriousness of a society of subsistence farmers,” said Mr Gurven.

“However,” Mr Gurven continued, “other industrious traits included being energetic, relaxed, and helpful. In small-scale societies, individuals have fewer choices for social or sexual partners, and limited domains of opportunity for cultural success and proficiency. This may require abilities that link aspects of different traits, resulting in a trait structure other than the Big Five.”

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