The ability of a society to imitate and learn, rather than individual smarts, may be why some cultures thrive and others disappear, scientists at the University of British Columbia said.
When people can observe and learn from a wider range of teachers, societies can better maintain technical skills and even increase the average skills of a group over successive generations, they said.
"This is the first study to demonstrate in a laboratory setting what archaeologists and evolutionary theorists have long suggested: that there is an important link between a society's sociality and the sophistication of its technology," UBC doctoral student in psychology Michael Muthukrishna said.
In the study, participants were asked to learn new skills -- digital photo editing and knot-tying -- then pass on what they learned to the next "generation" of participants.
The groups with greater access to experts accumulated significantly more skill than those with less access to teachers, the study found, and within 10 "generations" each member of the group with multiple mentors had stronger skills than the group limited to a single mentor.
Groups with greater access to experts also retained their skills much longer, sustaining higher levels of "cultural knowledge" over multiple generations, the researchers found.
The study has been published in the Proceedings of the Royal Academy: Biological Sciences.