Show simple item record

Files in this item


Item metadata

dc.contributor.authorBailey, Nathan W
dc.contributor.authorDesjonquères, Camille
dc.identifier.citationBailey , N W & Desjonquères , C 2021 , ' The indirect genetic effect interaction coefficient ψ : theoretically essential and empirically neglected ' , Journal of Heredity , vol. Advance Article , esab056 .
dc.identifier.otherPURE: 275956498
dc.identifier.otherPURE UUID: 5d385106-c19f-4bba-8e48-8e6edfb566cb
dc.identifier.otherPubMed: 34791332
dc.descriptionFunding: N.W.B. was funded by the UK Natural Environment Research Council (NE/T000619/1, NE/L011255/1), and C.D. was funded by a US National Science Foundation award (award no. 1855962).en
dc.description.abstractThe interaction effect coefficient ψ has been a much-discussed, fundamental parameter of indirect genetic effect (IGE) models since its formal mathematical description in 1997. The coefficient simultaneously describes the form of changes in trait expression caused by genes in the social environment and predicts the evolutionary consequences of those IGEs. Here, we report a striking mismatch between theoretical emphasis on ψ and its usage in empirical studies. Surveying all IGE research, we find that the coefficient ψ has not been equivalently conceptualized across studies. Several issues related to its proper empirical measurement have recently been raised, and these may severely distort interpretations about the evolutionary consequences of IGEs. We provide practical advice on avoiding such pitfalls. The majority of empirical IGE studies use an alternative variance-partitioning approach rooted in well-established statistical quantitative genetics, but several hundred estimates of ψ (from 15 studies) have been published. A significant majority are positive. In addition, IGEs with feedback, that is, involving the same trait in both interacting partners, are far more likely to be positive and of greater magnitude. Although potentially challenging to measure without bias, ψ has critically-developed theoretical underpinnings that provide unique advantages for empirical work. We advocate for a shift in perspective for empirical work, from ψ as a description of IGEs, to ψ as a robust predictor of evolutionary change. Approaches that "run evolution forward" can take advantage of ψ to provide falsifiable predictions about specific trait interactions, providing much-needed insight into the evolutionary consequences of IGEs.
dc.relation.ispartofJournal of Heredityen
dc.rightsCopyright © The American Genetic Association. 2021. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.en
dc.subjectIndirect genetic effecten
dc.subjectInteracting phenotypeen
dc.subjectInteraction coefficienten
dc.subjectSocial evolutionen
dc.subjectTrait-based analysisen
dc.subjectVariance partitioningen
dc.subjectQA Mathematicsen
dc.subjectQH301 Biologyen
dc.subjectQH426 Geneticsen
dc.titleThe indirect genetic effect interaction coefficient ψ : theoretically essential and empirically neglecteden
dc.typeJournal articleen
dc.description.versionPublisher PDFen
dc.contributor.institutionUniversity of St Andrews.Centre for Biological Diversityen
dc.contributor.institutionUniversity of St Andrews.School of Biologyen
dc.contributor.institutionUniversity of St Andrews.St Andrews Bioinformatics Uniten
dc.description.statusPeer revieweden

This item appears in the following Collection(s)

Show simple item record