Dispersal is a process of central importance for the ecological and evolutionary dynamics of populations and communities, because of its diverse consequences for gene flow and demography. It is subject to evolutionary change, which begs the question, what is the genetic basis of this potentially complex trait? To address this question, we (i) review the empirical literature on the genetic basis of dispersal, (ii) explore how theoretical investigations of the evolution of dispersal have represented the genetics of dispersal, and (iii) discuss how the genetic basis of dispersal influences theoretical predictions of the evolution of dispersal and potential consequences.
Dispersal has a detectable genetic basis in many organisms, from bacteria to plants and animals. Generally, there is evidence for significant genetic variation for dispersal or dispersal-related phenotypes or evidence for the micro-evolution of dispersal in natural populations. Dispersal is typically the outcome of several interacting traits, and this complexity is reflected in its genetic architecture: while some genes of moderate to large effect can influence certain aspects of dispersal, dispersal traits are typically polygenic. Correlations among dispersal traits as well as between dispersal traits and other traits under selection are common, and the genetic basis of dispersal can be highly environment-dependent.
By contrast, models have historically considered a highly simplified genetic architecture of dispersal. It is only recently that models have started to consider multiple loci influencing dispersal, as well as non-additive effects such as dominance and epistasis, showing that the genetic basis of dispersal can influence evolutionary rates and outcomes, especially under non-equilibrium conditions. For example, the number of loci controlling dispersal can influence projected rates of dispersal evolution during range shifts and corresponding demographic impacts. Incorporating more realism in the genetic architecture of dispersal is thus necessary to enable models to move beyond the purely theoretical towards making more useful predictions of evolutionary and ecological dynamics under current and future environmental conditions. To inform these advances, empirical studies need to answer outstanding questions concerning whether specific genes underlie dispersal variation, the genetic architecture of context-dependent dispersal phenotypes and behaviours, and correlations among dispersal and other traits.
Bibliographical noteM. S. thanks the European Research Council (IndependentStarting grant META-STRESS; 637412) and Academyof Finland (Decision numbers 273098 & 265461) forfunding. M. M. D. was supported by Ministeriode Economia y Competitividad ‘‘Ram´on y Cajalprogram’’ grant contract no. RYC-2014-16263. D. B.,E.A.F.,J.M.J.T.andE.M.arefundedby the FWO research community EVENET. D. B.is funded by FWO research grant INVADED G.018017.N.D. L., J. C., V. M. S. and M. B. are part of the Laboratoired’Excellence (LABEX) entitled TULIP (ANR-10-LABX-41).D. L. thanks Fyssen foundation for research funding.J. C. thanks an ANR-12-JSV7-0004-01. F. G. is supportedby SNSF grant PP00P3_144846. E. N. is supported byan International postdoctoral fellowship from the SwedishResearch Council (Vetenskapsr˚adet). E. A. F. thanks Eawagfor funding. J. M. B. thanks CEH for funding under projectNEC05264. C. G. thanks FCT (Fundac¸˜ao para a Ciencia e aTecnologia) for funding (FCT-ANR/BIA-BIC/0010/2013and IF Fellowship). M. B. and A. C. thank the ANRfor funding (INDHET program, ANR-12-BSV7-0023).V. M. S. thanks the ANR for funding (GEMS programANR-13-JSV7-0010-01). K. N. thanks the Ella and GeorgEhrnrooth Foundation and the Emil Aaltonen Foundationfor funding. E. M. is supported by UA-TOPBOF andFWO-project G030813N.
- dispersal kernel
- eco-evolutionary models
- gene flow
- genetic architecture
- genotype–environment interactions
- life-history traits