Children negotiate taking turns surprisingly early in life

BERLIN — From supermarket checkout lines to merge lanes on highways, adults often resolve social dilemmas by taking turns. Pairs of 5-year-old preschoolers can do it too, a new study finds. Children frequently work out deals to take turns when their interests collide, suggesting that this sophisticated strategy emerges surprisingly early in life.

By agreeing that each person will alternate in passing up a reward to avoid worse outcomes, duos of preschoolers earned a couple more colorful stickers than they would have otherwise, said psychology graduate student Sebastian Grüneisen of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Grüneisen presented his preliminary findings June 10 at the Summer Institute on Bounded Rationality, a weeklong set of seminars and workshops for young scientists, at the Max Planck Institute for Human Development.

“Five-year-olds can coordinate decisions with others in a fair way, even when each child has conflicting interests,” Grüneisen said.

Until now, researchers had not examined whether preschoolers are capable of forging and enforcing turn-taking agreements when competing for rewards, remarked psychologist Monika Keller of the Max Planck Institute for Human Development. Researchers suspected that children not yet in elementary school might not arrange and abide by equitable strategies, she said.

Grüneisen and psychologist Michael Tomasello, also of the Leipzig facility, asked 10 pairs of 5-year-old boys and 10 pairs of 5-year-old girls to play a game in which each child steered a toy train carrying three marbles, which could be exchanged for stickers at the end of the game. The trains moved in opposite directions on a single track. One child had to swerve his or her train onto a ramp to avoid a crash that would cause both children to lose their marbles. A child who swerved kept only one marble; the child’s partner, who was able to drive straight through, got three marbles.

A screen between players blocked their view of each other, although they could talk freely. Each pair of kids played the game 12 times.

Half of the duos decided to take turns swerving. In those pairs, turns were taken on five to 12 trials. Most remaining pairs played a form of “chicken,” in which both players said they would drive straight through but one consistently swerved. Boys and girls displayed comparable tendencies to choose a turn-taking approach to the game.

Turn-taking pairs earned an average of about 40 stickers, versus approximately 38 stickers for pairs that never swerved on alternate trials.

Grüneisen is currently looking at whether individual 5-year-olds can work out turn-taking strategies with a revolving cast of three partners in a version of the train game. He also wants to examine how 5-year-olds use promises or protests to ensure that a partner abides by a turn-taking agreement.