Do Monozygotic Twins Have Higher Genetic Quality than Dizygotic Twins and Singletons? Hints from Attractiveness Ratings and Self-Reported Health

  • Satoshi KanazawaEmail author
  • Nancy L. Segal
Research Article


Evolutionary theories generally concur that sexual reproduction and genetic recombination evolved to maximize genetic variability. Thus, the existence of monozygotic (MZ) twins, which do not take advantage of genetic recombination for each offspring, poses a puzzle. Evolutionary logic of inclusive fitness suggests that parents with high-quality genes may be more likely to produce MZ twins. Analyses of data from the National Longitudinal Study of Adolescent to Adult Health show that MZ twins were significantly more physically attractive and healthier than dizygotic (DZ) twins and singletons. These results suggest that MZ twins may possess higher-quality genes than DZ twins and singletons, and support one of the first evolutionary theories of MZ twinning that specifies its ultimate functions.


Twin research Monozygotic twin conception Add Health 



We thank Typhaine Christiaen, Scott Forbes, and David Haig for their comments on earlier drafts.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.


  1. Aston, K. I., Peterson, C. M., & Carrell, D. T. (2008). Monozygotic twinning associated with assisted reproductive technologies: A review. Reproduction, 136, 377–386.CrossRefGoogle Scholar
  2. Boklage, C. E. (1981). On the distribution of nonrighthandedness among twins and their families. Acta Geneticae Medicae et Gemellologiae: Twin Research, 30, 167–187.CrossRefGoogle Scholar
  3. Catalano, R., Ahren, J., Bruckner, T., Anderson, E., & Saxton, K. (2009). Gender-specific selection in utero among contemporary human birth cohorts. Paediatric and Perinatal Epidemiology, 23, 273–278.CrossRefGoogle Scholar
  4. Catalano, R. A., Saxton, K. B., Bruckner, T. A., Pearl, M., Anderson, E., Goldman-Mellor, S., et al. (2012). Hormonal evidence supports the theory of selection in utero. American Journal of Human Biology, 24, 526–532.CrossRefGoogle Scholar
  5. Christensen, K., Vaupel, J. W., Holm, N. V., & Yashin, A. I. (1995). Mortality among twins after age 6: Fetal origins hypothesis versus twin method. British Medical Journal, 310, 432–436.CrossRefGoogle Scholar
  6. Costner, H. L. (1969). Theory, deduction, and rules of correspondence. American Journal of Sociology, 75, 245–263.CrossRefGoogle Scholar
  7. Craig, S. F., Slobodkin, L. B., Wray, G. A., & Biermann, C. H. (1997). The ‘paradox’ of polyembryony: A review of the cases and a hypothesis for its evolution. Evolutionary Ethology, 11, 127–143.Google Scholar
  8. Dube, J., Dodds, L., & Armson, B. A. (2002). Does chorionicity or zygosity predict adverse perinatal outcomes in twins? American Journal of Obstetrics and Gynecology, 186, 579–583.CrossRefGoogle Scholar
  9. Forbes, S. (2017). Embryo quality: The missing link between pregnancy sickness and pregnancy outcome. Evolution and Human Behavior, 38, 265–278.CrossRefGoogle Scholar
  10. Frazier, T. W., Thompson, L., Youngstrum, E. A., Law, P., Hardan, E. Y., Eng, C., & Morris, N. (2014). A twin study of heritable and shared environmental contributions to autism. Journal of Autism and Developmental Disorders, 44, 2013–2025.CrossRefGoogle Scholar
  11. Gangestad, S. W., Thornhill, R., & Yeo, R. A. (1994). Facial attractiveness, developmental stability, and fluctuating asymmetry. Ethology and Sociobiology, 15, 73–85.CrossRefGoogle Scholar
  12. Gleeson, S. K., Clark, A. B., & Dugatkin, L. A. (1994). Monozygotic twinning: An evolutionary hypothesis. Proceedings of the National Academy of Sciences of the United States of America, 91, 11363–11367.CrossRefGoogle Scholar
  13. Hadfield, J. D., Wilson, A. J., Garant, D., Sheldon, B. C., & Kruuk, L. E. B. (2010). The misuse of BLUP in ecology and evolution. American Naturalist, 175, 116–125.CrossRefGoogle Scholar
  14. Harris, K. M., Halpern, C. T., Smolen, A., & Haberstick, B. C. (2006). The National Longitudinal Study of Adolescent Health (Add Health) twin data. Twin Research and Human Genetics, 9, 988–997.CrossRefGoogle Scholar
  15. Hjelmborg, J. V. B., Iachine, I., Skytthe, A., Vaupel, J. W., McGue, M., Koskenvuo, M., et al. (2006). Genetic influence on human lifespan and longevity. Human Genetics, 119, 312–321.CrossRefGoogle Scholar
  16. Houslay, T. M., & Wilson, A. J. (2017). Avoiding the misuse of BLUP in behavioral ecology. Behavioral Ecology, 28, 948–952.CrossRefGoogle Scholar
  17. Kanazawa, S. (2011). Intelligence and physical attractiveness. Intelligence, 39, 7–14.CrossRefGoogle Scholar
  18. Kanazawa, S., & Still, M. C. (2018). Is there really a beauty premium or an ugliness penalty on earnings? Journal of Business and Psychology, 33, 249–262.CrossRefGoogle Scholar
  19. Kondrashov, A. S. (1993). Classification of hypotheses on the advantage of amphimixis. Journal of Heredity, 84, 372–387.CrossRefGoogle Scholar
  20. Langlois, J. H., Kalakanis, L., Rubenstein, A. J., Larson, A., Hallam, M., & Smoot, M. (2000). Maxims or myths of beauty? A meta-analytic and theoretical review. Psychological Bulletin, 126, 390–423.CrossRefGoogle Scholar
  21. Langlois, J. H., & Roggman, L. A. (1990). Attractive faces are only average. Psychological Science, 1, 115–121.CrossRefGoogle Scholar
  22. Loos, R., Derom, C., Vlietinck, R., & Derom, R. (1998). The East Flanders Prospective Twin Survey (Belgium): A population-based register. Twin Research and Human Genetics, 1, 167–175.Google Scholar
  23. McGovern, R. J., Neale, M. C., & Kendler, K. S. (1996). The independence of physical attractiveness and symptoms of depression in a female twin population. Journal of Psychology, 130, 209–219.CrossRefGoogle Scholar
  24. Mealey, L., Bridgstock, R., & Townsend, G. C. (1999). Symmetry and perceived facial attractiveness: A monozygotic co-twin comparison. Journal of Personality and Social Psychology, 76, 151–158.CrossRefGoogle Scholar
  25. Mitchem, D. G., Purkey, A. M., Grebe, N. M., Carey, G., Garver-Apgar, C. E., Bates, T. C., et al. (2014). Estimating the sex-specific effects of genes on facial attractiveness and sexual dimorphism. Behavior Genetics, 44, 270–281.CrossRefGoogle Scholar
  26. Nedelec, J. L., & Beaver, K. M. (2011). Beauty is in the sex of the beholder: An examination of the effects of interviewer characteristics on assessments of respondent attractiveness. Personality and Individual Differences, 51, 930–934.CrossRefGoogle Scholar
  27. Otto, S. P., & Lenormand, T. (2002). Resolving the paradox of sex and recombination. Nature Reviews Genetics, 3, 252–261.CrossRefGoogle Scholar
  28. Parsons, P. A. (1990). Fluctuating asymmetry: An epigenetic measure of stress. Biological Reviews, 65, 131–145.CrossRefGoogle Scholar
  29. Parsons, P. A. (1992). Fluctuating asymmetry: A biological monitor of environmental and genomic stress. Heredity, 68, 361–364.CrossRefGoogle Scholar
  30. Perrett, D. I., Burt, M., Penton-Voak, I. S., Lee, K. J., Rowland, D. A., & Edwards, R. (1999). Symmetry and human facial attractiveness. Evolution and Human Behavior, 20, 295–307.CrossRefGoogle Scholar
  31. Rubenstein, A. J., Langlois, J. H., & Roggman, L. A. (2002). What makes a face attractive and why: The role of averageness in defining facial beauty. In G. Rhodes & L. A. Zebrowitz (Eds.), Facial attractiveness: Evolutionary, cognitive, and social perspectives (pp. 1–33). Westport, CT: Ablex.Google Scholar
  32. Rustico, M. A., Baietti, M. G., Coviello, D., Orlandi, E., & Nicolini, U. (2005). Managing twins discordant for fetal anomaly. Prenatal Diagnosis, 25, 766–771.CrossRefGoogle Scholar
  33. Segal, N. L. (2000). Entwined lives: Twins and what they tell us about human behavior. New York: Plume.Google Scholar
  34. Segal, N. L. (2011). Twin, adoption and family methods as approaches to the evolution of individual differences. In D. M. Buss & P. Hawley (Eds.), The evolution of personality and individual differences (pp. 303–337). Oxford: Oxford University Press.Google Scholar
  35. Segal, N. L. (2012). Born together—Reared apart: The landmark Minnesota Twin Study. Cambridge: Harvard University Press.CrossRefGoogle Scholar
  36. Segal, N. L. (2017). Twin mythconceptions: False beliefs, fables, and facts about twins. Amsterdam: Elsevier.Google Scholar
  37. Sharrow, D. J., & Anderson, J. J. (2016). A twin protection effect? Explaining twin survival advantages with a two-process mortality model. PLoS ONE, 11, e0154774.CrossRefGoogle Scholar
  38. Souter, V. L., Kapur, R. P., Nyholt, D. R., Skogerboe, K., Myerson, D., Ton, C. C., et al. (2003). A report of dizygous monochorionic twins. New England Journal of Medicine, 349, 154–158.CrossRefGoogle Scholar
  39. Sperling, L., Kiil, C., Larsen, L. U., Brocks, V., Wojdemann, K. R., Qvist, I., et al. (2007). Detection of chromosomal abnormalities, congenital abnormalities and transfusion syndrome in twins. Ultrasound in Obstetrics and Gynecology, 29, 517–526.CrossRefGoogle Scholar
  40. Thornhill, R., & Gangestad, S. W. (1993). Human facial beauty: Averageness, symmetry, and parasite resistance. Human Nature, 4, 237–269.CrossRefGoogle Scholar
  41. Thornhill, R., & Møller, A. P. (1997). Developmental stability, disease and medicine. Biological Reviews, 72, 497–548.CrossRefGoogle Scholar
  42. Williams, G. C., & Mitton, J. B. (1973). Why reproduce sexually? Journal of Theoretical Biology, 39, 545–554.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of ManagementLondon School of Economics and Political ScienceLondonUK
  2. 2.Department of PsychologyCalifornia State University-FullertonFullertonUSA

Personalised recommendations