Related Experiment Video
Updated: May 29, 2026
10:20
Simultaneous Assessment of Kinship, Division Number, and Phenotype via Flow Cytometry for Hematopoietic Stem and Progenitor Cells
Published on: March 24, 2023
Is friendship akin to kinship?
Joshua M Ackerman1, Douglas T Kenrick, Mark Schaller
1Department of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA.
Summary
Women treat close friends more like family than men do, especially regarding incest avoidance and nepotism. This suggests gender-specific cognitive processes in close relationships.
Area of Science:
- Evolutionary Psychology
- Social Psychology
- Cognitive Science
Background:
- Close friendships are often considered genetically equivalent to stranger relationships.
- However, evolutionary reasoning suggests that close friendships might activate kinship-related processes, particularly in women.
Purpose of the Study:
- To investigate whether close friendships elicit kinship-like responses in humans.
- To examine gender differences in the treatment of friends, kin, and strangers in domains of functional significance.
Main Methods:
- Two studies were conducted comparing responses to strangers, friends, and kin.
- Study 1: Assessed emotional responses to imagined sexual contact with kin, friends, and strangers.
- Study 2: Evaluated benevolent attributions towards actual kin, friends, and strangers.
Main Results:
- Women exhibited kin-like emotional responses towards friends in imagined incest scenarios, unlike men.
- Women made more benevolent attributions to friends, similar to their attributions to kin.
- Men's attributions to friends were more akin to their attributions to strangers.
Conclusions:
- Findings support a domain-specific rather than a domain-general model of intimate relationships.
- Results suggest that women's close friendships may activate kinship-specific cognitive and affective processes.
- The study highlights potential sex differences in the modular structure of social cognition.
Related Concept Videos
01:20Friendships and Close Friendships
Friendship formation is a dynamic process shaped by psychological, cultural, and social factors. Friendships play a crucial role in emotional well-being, social development, and personal identity from childhood to adulthood.Childhood and Early FriendshipsFriendships in childhood often arise due to shared environments, such as school or neighborhood interactions. At this stage, proximity and common interests serve as the primary basis for connection. As children grow, their friendships evolve...
02:12Relationship Formation
What do you think is the single most influential factor in determining with whom you become friends and whom you form romantic relationships? You might be surprised to learn that the answer is simple: the people with whom you have the most contact. This most important factor is proximity. You are more likely to be friends with people you have regular contact with. For example, there are decades of research that shows that you are more likely to become friends with people who live in your dorm,...
01:27Relationship Growth
Interpersonal relationships progress through stages, beginning with awareness and moving toward mutuality, where emotional connections deepen. While many relationships remain at moderate levels of mutuality, deeper connections form through self-disclosure, trust, and interdependence.Self-DisclosureSelf-disclosure involves revealing personal information, starting with surface-level details and gradually progressing to more intimate content. As trust grows, individuals feel more comfortable...
00:57Inclusive Fitness
Most altruistic behavior—in which one animal helps another at a cost to themselves—occurs between relatives. Scientists think these altruistic behaviors evolved because they increase the inclusive fitness of the animal providing help.
01:29Relationship with Other Adult Family Members and Siblings
Other adult family members and siblings play a crucial role in shaping children’s social and emotional development. While parents or primary caregivers are often the central figures in early attachment and socialization, other adults in a child’s life, such as grandparents, aunts, and uncles, can significantly influence developmental outcomes. These influences depend on each adult’s personality and may help compensate when a primary caregiver is emotionally distant or inconsistent. For...
01:27Companionate Love
Companionate love is a fundamental aspect of long-term relationships, characterized by deep affection, mutual respect, and emotional intimacy. Unlike passionate love, which is driven by intense emotions and physical attraction but often declines over time, companionate love remains stable and can even strengthen with shared experiences and commitment. Psychological and biological mechanisms underpin this enduring form of love, influencing relationship longevity and satisfaction.Stability and...