, Volume 190, Issue 17, pp 3909–3928 | Cite as


  • Grant Ramsey


In this paper, I argue (contra some recent philosophical work) that an objective distinction between natural selection and drift can be drawn. I draw this distinction by conceiving of drift, in the most fundamental sense, as an individual-level phenomenon. This goes against some other attempts to distinguish selection from drift, which have argued either that drift is a population-level process or that it is a population-level product. Instead of identifying drift with population-level features, the account introduced here can explain these population-level features based on a property that I label driftability. Additionally, this account shows that biology’s “first law”—the Principle of Drift (Brandon, J Phil 102(7):319–335 2006)—is not a foundational law, but is a consequence of driftability.


Drift Fitness Selection Evolution Population Individual 



This paper was the subject of a symposium at the 2011 meeting of the Pacific Division of the American Philosophical Association. I thank my commentators, Vadim Keyser, Mohan Matthen, and Sarah Roe for their insightful comments. This paper was also presented at the 2011 Workshop on Metaphysics of Microevolutionary Processes at the University of Alabama at Birmingham. I thank the organizer, Marshall Abrams, as well as the other attendees for their input. I also thank Robert Brandon, Yoichi Ishida, Bence Nanay, Charles Pence, and the anonymous reviewers for reading and commenting on earlier versions of this paper.


  1. Abrams, M. (2007). How do natural selection and random drift interact? In: C. Bicchieri & J. Alexander (Eds.), Proceedings of the 2006 biennial meeting of the Philosophy of Science Association. Part I: Contributed papers. Philosophy of Science, 74(5), 666–679.Google Scholar
  2. Ariew, A., & Ernst, Z. (2009). What fitness can’t be. Erkenntnis, 71(3), 289–301.CrossRefGoogle Scholar
  3. Ariew, A., & Lewontin, R. C. (2004). The confusions of fitness. British Journal for the Philosophy of Science, 55, 347–363.CrossRefGoogle Scholar
  4. Beatty, J. H. (1984). Chance and natural selection. Philosophy of Science, 51, 183–211.CrossRefGoogle Scholar
  5. Beatty, J. H., & Finsen, S. (1989). Rethinking the propensity interpretation of fitness: A peek inside pandora’s box. In M. Ruse (Ed.), What the philosophy of biology is: Essays for David Hull (pp. 17–30). Dordrecht: Kluwer.CrossRefGoogle Scholar
  6. Bouchard, F., & Rosenberg, A. (2004). Fitness, probability and the principles of natural selection. British Journal for the Philosophy of Science, 55(4), 693–712.CrossRefGoogle Scholar
  7. Brandon, R. N. (1978). Adaptation and evolutionary theory. Studies in History and Philosophy of Science, 9(3), 181–206.CrossRefGoogle Scholar
  8. Brandon, R. N. (2005). The difference between selection and drift: A reply to Millstein. Biology and Philosophy, 20(1), 153–170.CrossRefGoogle Scholar
  9. Brandon, R. N. (2006). The principle of drift: Biology’s first law. Journal of Philosophy, 102(7), 319–335.Google Scholar
  10. Brandon, R. N., & Carson, S. (1996). The indeterministic character of evolutionary theory: No ‘no hidden variables proof’ but no room for determinism either. Philosophy of Science, 63(3), 315–337.CrossRefGoogle Scholar
  11. Darwin, C. (1859). On the origin of species. London: John Murray.Google Scholar
  12. Gildenhuys, P. (2009). An explication of the causal dimension of drift. British Journal for the Philosophy of Science, 60(3), 521–555.CrossRefGoogle Scholar
  13. Haldane, J. B. S. (1927). A mathematical theory of natural and artificial selection, part v: Selection and mutation. Proceedings of the Cambridge Philosophical Society (pp. 838–844). Oxford: Oxford University Press.Google Scholar
  14. Haldane, J. B. S. (1954). The measurement of natural selection. Proceedings on IX International Congress Genetics, 1, 480–487.Google Scholar
  15. Krimbas, C. B. (2004). On fitness. Biology and Philosophy, 19(2), 185–203.CrossRefGoogle Scholar
  16. McGraw, J. B., & Caswell, H. (1996). Estimation of individual fitness from life-history data. American Naturalist, 147(1), 47–64.CrossRefGoogle Scholar
  17. Matthen, M. (2009). Drift and “statistically abstractive explanation. Philosophy of Science, 76, 464–487.CrossRefGoogle Scholar
  18. Matthen, M., & Ariew, A. (2002). Two ways of thinking about fitness and natural selection. Journal of Philosophy, 99(2), 55–83.CrossRefGoogle Scholar
  19. McShea, D., & Brandon, R. N. (2010). Biology’s first law: The tendency for diversity and complexity to increase in evolutionary systems. Chicago: University of Chicago Press.CrossRefGoogle Scholar
  20. Mills, S. K., & Beatty, J. H. (1979). The propensity interpretation of fitness. Philosophy of Science, 46(2), 263–286.CrossRefGoogle Scholar
  21. Millstein, R. L. (2002). Are random drift and natural selection conceptually distinct? Biology and Philosophy, 17, 33–53.CrossRefGoogle Scholar
  22. Millstein, R. L. (2006). Natural selection as a population-level causal process. The British Journal for the Philosophy of Science, 57(4), 627–653.CrossRefGoogle Scholar
  23. Pence, C., Ramsey, G. (forthcoming). A new foundation for the propensity interpretation of fitness. British Journal for the Philosophy of Science.Google Scholar
  24. Pfeifer, J. (2005). Why selection and drift might be distinct. Philosophy of Science, 72(5), 1135–1145.CrossRefGoogle Scholar
  25. Rosenberg, A. (1994). Instrumental biology or the disunity of science. Chicago: University of Chicago Press.Google Scholar
  26. Sober, E. (1984). The nature of selection. London: MIT Press.Google Scholar
  27. Sober, E. (2001). The two faces of fitness. In E. Sober (Ed.), Conceptual issues in evolutionary biology (pp. 25–38). London: MIT Press.Google Scholar
  28. Sober, E. (2010). Evolutionary theory and the reality of macro-probabilities. In E. Ellery & J. H. Fetzered (Eds.), The place of probability in science (pp. 133–161). New York: Springer.CrossRefGoogle Scholar
  29. Stephens, C. (2004). Selection, drift, and the ’forces’ of evolution. Philosophy of Science, 71(4), 550–570.CrossRefGoogle Scholar
  30. Wagner, G. (2010). The measurement theory of fitness. Evolution, 64(5), 1358–1376.Google Scholar
  31. Walsh, D. (2007). The pomp of superfluous causes: The interpretation of evolutionary theory. Philosophy of Science, 74(3), 281–303.CrossRefGoogle Scholar
  32. Walsh, D. M., Lewens, T., & Ariew, A. (2002). The trials of life: Natural selection and random drift. Philosophy of Science, 69(3), 452–473.CrossRefGoogle Scholar
  33. Woodward, J. F. (2005). Making things happen: A theory of causal explanation. Oxford: Oxford University Press.Google Scholar

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© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  1. 1.Department of PhilosophyUniversity of Notre DameNotre DameUSA

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