Fisher's fundamental theorem of natural selection

Fisher's fundamental theorem of natural selection is an idea about genetic variance[1][2] in population genetics developed by the statistician and evolutionary biologist Ronald Fisher. The proper way of applying the abstract mathematics of the theorem to actual biology has been a matter of some debate, however, it is a true theorem.[3]

It states:

"The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time."[4]

Or in more modern terminology:

"The rate of increase in the mean fitness of any organism, at any time, that is ascribable to natural selection acting through changes in gene frequencies, is exactly equal to its genetic variance in fitness at that time".[5]
  1. ^ Crow, J.F. (2002). "Here's to Fisher, additive genetic variance, and the fundamental theorem of natural selection". Perspective. Evolution. 56 (7): 1313–1316. doi:10.1554/0014-3820(2002)056[1313:phstfa]2.0.co;2. PMID 12206233. S2CID 198157405.
  2. ^ Lessard, Sabin (1997). "Fisher's Fundamental Theorem of Natural Selection Revisited". Theoretical Population Biology. 52 (2): 119–136. doi:10.1006/tpbi.1997.1324. PMID 9356328.
  3. ^ Plutynski, Anya (2006). "What was Fisher's fundamental theorem of natural selection and what was it for?". Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences. 37 (1): 59–82. doi:10.1016/j.shpsc.2005.12.004.
  4. ^ Fisher, R.A. (1930). The Genetical Theory of Natural Selection. Oxford, UK: Clarendon Press.
  5. ^ Edwards, A.W.F. (1994). "The fundamental theorem of natural selection". Biological Reviews. 69 (4): 443–474. doi:10.1111/j.1469-185x.1994.tb01247.x. PMID 7999947. S2CID 10052338.