Homage to Felsenstein 1981, or why are there so few/many species?

Journal Article (Journal Article)

If there are no constraints on the process of speciation, then the number of species might be expected to match the number of available niches and this number might be indefinitely large. One possible constraint is the opportunity for allopatric divergence. In 1981, Felsenstein used a simple and elegant model to ask if there might also be genetic constraints. He showed that progress towards speciation could be described by the build-up of linkage disequilibrium among divergently selected loci and between these loci and those contributing to other forms of reproductive isolation. Therefore, speciation is opposed by recombination, because it tends to break down linkage disequilibria. Felsenstein then introduced a crucial distinction between "two-allele" models, which are subject to this effect, and "one-allele" models, which are free from the recombination constraint. These fundamentally important insights have been the foundation for both empirical and theoretical studies of speciation ever since.

Full Text

Duke Authors

Cited Authors

  • Butlin, RK; Servedio, MR; Smadja, CM; Bank, C; Barton, NH; Flaxman, SM; Giraud, T; Hopkins, R; Larson, EL; Maan, ME; Meier, J; Merrill, R; Noor, MAF; Ortiz-Barrientos, D; Qvarnström, A

Published Date

  • May 1, 2021

Published In

Volume / Issue

  • 75 / 5

Start / End Page

  • 978 - 988

PubMed ID

  • 33870499

Electronic International Standard Serial Number (EISSN)

  • 1558-5646

International Standard Serial Number (ISSN)

  • 0014-3820

Digital Object Identifier (DOI)

  • 10.1111/evo.14235


  • eng