Openness is related to proenvironmental behavior both within and across families

Environment-friendly behaviors may be desirable in helping to solve world-wide ecological issues. This has sparked interest in the associations of such behaviors with established psychological constructs such as the Five-Factor Model personality traits. Of these, Openness has been most consistently linked with pro-environmental behavior, yet the extent of causality in this association is unclear. Using a sample of 168 individuals, including 84 sibling pairs, the present study replicated the association while controlling for factors in which families differ (environmental factors that siblings share and a proportion of genetic variance). Pro-environmental behavior was correlated with Openness (r = .51) and the association could be observed both between (r = .57) and within families (r = .29), with adjustments for various demographic variables. These findings indicate that more open individuals tend to engage in pro-environmental behaviors, even when controlling for possibly confounding factors shared and not shared between siblings.