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Teamwork made humans brainier: study

A group of people holding hands

Teamwork and bigger brainpower fed off each other, says one researcher (Source: Julia Freeman-Woolpert/stock.xchng)

Brain expansion Learning to work in teams may explain why humans evolved a bigger brain, according to a new study.







In both cases, the individual would gain more from selfishness.


"We cooperate in large groups of unrelated individuals quite frequently, and that requires cognitive abilities to keep track of who is doing what to you and change your behaviour accordingly," says co-author Luke McNally of Dublin's Trinity College.

Keeping tabs


"If you cooperate and I cheat, then next time we interact you could decide: 'Oh well, he cheated last time, so I won't cooperate with him.' So basically you have to cooperate in order to receive cooperation in the future."

McNally says teamwork and bigger brainpower fed off each other.

"Transitions to cooperative, complex societies can drive the evolution of a bigger brain," he says.

"Once greater levels of intelligence started to evolve, you saw cooperation going much higher."

Physiological limits


But he says there were physiological limits to cooperation.

Humans would need a "house-sized brain" to take cooperation to a perfect level on a planet filled with humans.

"Our current brain size limits the community size that we can manage ... that we feel we belong to," he says.

Our comfortable "personal social network" is limited to about 150, and boosting that to 500 would require a doubling of the size of the brain.

"In order to create greater social integration, greater social cohesion even on the size of France, never mind the size of the EU, never mind the planet, we probably have to find other ways of doing it" than wait for evolution, says Dunbar.

Tags: anthropology-and-sociology, evolution, neuroscience