Environmentalists were sought after as cooperation partners and elicited more cooperation from others, though they didn't behave more cooperatively

Pro-environmental behavior as a signal of cooperativeness: Evidence from a social dilemma experiment. Stepan Vesely, Christian A. Klöckner, Cameron Brick. Journal of Environmental Psychology, October 18 2019, 101362. https://doi.org/10.1016/j.jenvp.2019.101362

Highlights
•    One's environmental behavior influences how others see and behave towards the actor.
•    People who behave pro-environmentally are expected to be more cooperative.
•    People who behave pro-environmentally are preferred as interaction partners.
•    People who behave pro-environmentally elicit more cooperation from others.
•    Results were obtained in incentivized decision tasks.

Abstract: Pro-environmental behavior has social signaling value. Previous research suggests that enacting pro-environmental behaviors can signal certain personal characteristics, such as social status and trustworthiness, to others. Using an incentivized experiment, we show that people known to behave pro-environmentally are expected to be more cooperative, are preferred as cooperation partners, and elicit more cooperation from others. The presence of pro-environmental individuals may thus motivate others to exert more effort towards reaching cooperative goals, even in situations where individual and group goals are at odds (i.e., social dilemmas). However, people who behaved pro-environmentally were actually no more cooperative than those performing fewer pro-environmental behaviors.