Encyclopedia of Evolutionary Psychological Science

Living Edition
| Editors: Todd K. Shackelford, Viviana A. Weekes-Shackelford


Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-16999-6_2460-1



People who are related by descent (including adoption) and marriage


In every human society, people identify certain others as family. These social relationships are an important part of people’s lives, with family (or descent) groups being the main unit of social organization in many societies. While kinship is a human universal, norms about who is considered family, and the expectations and obligations of family members vary cross-culturally. Family tends to include those related by descent and marriage. Kin are typically categorized as consanguineal, meaning related by descent, or affinal, meaning related by marriage. Given that humans are a social species, family relationships influence many aspects of people’s lives.

Evolutionary Perspectives

When examining family from an evolutionary perspective, researchers tend to focus on those individuals who are biologically related. This is because help to kin, and its amount, can be...


Reproductive Conflict Sexual Conflict Theory Delay Reproduction Cooperative Breeding Biological Offspring 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.


  1. Burton-Chellew, M. N., & Dunbar, R. I. M. (2011). Are affines treated as biological kin? Current Anthropology, 52(5), 741–746.  https://doi.org/10.1086/661288.CrossRefGoogle Scholar
  2. Cant, M. A., & Johnstone, R. A. (2008). Reproductive conflict and the separation of reproductive generations in humans. Proceedings of the National Academy of Sciences, 105(14), 5332–5336.  https://doi.org/10.1073/pnas.0711911105.CrossRefGoogle Scholar
  3. Ellis, B. J., Figueredo, A. J., Brumbach, B. H., & Schlomer, G. L. (2009). Fundamental dimensions of environmental risk: The impact of harsh versus unpredictable environments on the evolution and development of life history strategies. Human Nature, 20(2), 204–268.  https://doi.org/10.1007/s12110-009-9063-7.CrossRefPubMedGoogle Scholar
  4. Geronimus, A. T. (2003). Damned if you do: Culture, identity, privilege, and teenage childbearing in the United States. Social Science & Medicine, 57(5), 881–893.  https://doi.org/10.1016/S0277-9536(02)00456-2.CrossRefGoogle Scholar
  5. Gibson, K. (2009). Differential parental investment in families with both adopted and genetic children. Evolution and Human Behavior, 30(3), 184–189.  https://doi.org/10.1016/j.evolhumbehav.2009.01.001.CrossRefGoogle Scholar
  6. Hamilton, W. D. (1964). The genetical evolution of social behaviour I & II. Journal of Theoretical Biology, 7, 1–52.CrossRefGoogle Scholar
  7. Hrdy, S. B. (2005). Evolutionary context of human development: The cooperative breeding model. In C. S. Carter, L. Ahnert, K. E. Grossmann, S. B. Hrdy, M. E. Lamb, S. W. Porges, & N. Sachser (Eds.), Attachment and bonding: A new synthesis (pp. 9–32). Cambridge, MA: MIT Press.Google Scholar
  8. Kaplan, H. (1994). Evolutionary and wealth flows theories of fertility: Empirical tests and new models. Population and Development Review, 20(4), 753–791.CrossRefGoogle Scholar
  9. Lee, R. D., & Kramer, K. L. (2002). Children’s economic roles in the Maya family life cycle: Cain, Caldwell, and Chayanov revisited. Population and Development Review, 28(3), 475–499.CrossRefGoogle Scholar
  10. Moya, C., & Sear, R. (2014). Intergenerational conflicts may help explain parental absence effects on reproductive timing: A model of age at first birth in humans. PeerJ, 2, e512.  https://doi.org/10.7717/peerj.512.CrossRefPubMedPubMedCentralGoogle Scholar
  11. Silk, J. B. (1980). Adoption and kinship in Oceania. American Anthropologist, 82(4), 799–820.  https://doi.org/10.1525/aa.1980.82.4.02a00050.CrossRefGoogle Scholar
  12. Webster, G. D., Graber, J. A., Gesselman, A. N., Crosier, B. S., & Schember, T. O. (2014). Life history theory of father absence and menarche: A meta-analysis. Evolutionary Psychology, 12(2), 273–294.  https://doi.org/10.1177/147470491401200202.CrossRefPubMedGoogle Scholar

Authors and Affiliations

  1. 1.Department of AnthropologyBoise State UniversityBoiseUSA

Section editors and affiliations

  • Carey Fitzgerald
    • 1
  1. 1.University of South Carolina – BeaufortBlufftonUSA