Evolution and ClosE RElationships

Throughout history, humans have faced critical challenges that included finding a mate, keeping that mate, caring for kin, forming coalitions, and gaining some status. Solving each of these ancestral challenges involved forming a different type of social relationship. An evolutionary perspective suggests that there is a set of fundamentally different types of close relationships associated with different evolutionary challenges. These types include (a) mate attraction (e.g., dating couples), (b) mate retention (e.g., married couples), (c) kin care (e.g., family members), (d) coalition formation (e.g., friends), and (e) status (e.g., workplace relationships). Each type of ancestral challenge is associated with different kinds of evolutionary opportunities and costs, suggesting that different types of relationships may be governed by a different relationship-specific psychology. In this chapter, we review the principles of evolutionary psychology and their implications for close relationships. Although some animals spend most of their lives as hermits, humans have always lived in groups. The human brain has evolved for social relationships (Kenrick, Griskevicius, Neuberg, & Schaller, 2010; Kenrick, Neuberg, & White, in press). But although people are born ready to love and relate to other people, relationships differ in several important ways. For example, the words I love you can be spoken by a parent to a newborn baby, by a young man to a woman he met yesterday at a beach resort in Mexico, and by a heterosexual woman to her best female friend. Yet parental love is not the same as romantic love, which is still different from platonic love between friends. In this chapter, we consider social relationships from an evolutionary perspective. This perspective contends that, throughout history, humans have faced a set of core ancestral challenges, which include attracting a mate, keeping that mate, caring for kin, forming coalitions, and attaining status. An evolutionary perspective suggests that each type of challenge can be solved by forming different types of relationships. These relationship types include (a) dating couples, (b) married couples, (c) family members, (d) friends, and (e) coworkers (see Table 1.1). Each type of relationship is associated with different kinds of evolutionary opportunities and costs, meaning that people need different things from different types of intimate others and must provide different things to those intimate others. These needs and provisions vary systematically depending on the type of relationship. In this chapter, we first briefly review what it means to take an evolutionary perspective, reviewing some foundational principles. We then discuss each of the five types of relationships, reviewing relevant theory and findings. Finally, we discuss emerging themes and future directions in the study of social relationships from an evolutionary perspective.