Data from: Social learning and the demise of costly cooperation in humans

Humans have a sophisticated ability to learn from others, termed social
learning, which has allowed us to spread over the planet, construct
complex societies, and travel to the moon. It has been hypothesized that
social learning has played a pivotal role in making human societies
cooperative, by favouring cooperation even when it is not favoured by
genetical selection. However, this hypothesis lacks direct experimental
testing, and the opposite prediction has also been made, that social
learning disfavours cooperation. We experimentally tested how different
aspects of social learning affect the level of cooperation in public-goods
games. We found that: (i) social information never increased cooperation
and usually led to decreased cooperation; (ii) cooperation was lowest when
individuals could observe how successful individuals behaved; and (iii)
cooperation declined because individuals preferred to copy successful
individuals, who cooperated less, rather than copy common behaviours.
Overall, these results suggest that individuals use social information to
try and improve their own success, and that this can lead to lower levels
of cooperation.