“…For decades, researchers across the social and natural sciences have investigated what makes individuals choose to engage in cooperation despite the personal costs involved (Axelrod & Hamilton, 1981; Batson, Duncan, Ackerman, Buckley, & Birch, 1981; R. Campbell & Sowden, 1985; Chakroff & Young, 2014; Chudek & Henrich, 2011; Cushman & Macindoe, 2009; Galinsky & Schweitzer, 2015; Hamlin, Wynn, & Bloom, 2007; Kiyonari, Tanida, & Yamagishi, 2000; Kraft-Todd, Yoeli, Bhanot, & Rand, 2015; Paluck, Shepherd, & Aronow, 2016; Raihani, Thornton, & Bshary, 2012; Rand & Nowak, 2013; Tooby & Cosmides, 1990; Van Lange, De Bruin, Otten, & Joireman, 1997). …”