Reproductive isolation with a learned trait in a structured population

Abstract

Assortative mating displays and/or preferences can be affected by learning across a wide range of animal taxa, but the specifics of how this learning affects speciation with gene flow are not well understood. We use population genetic models with trait learning to investigate how the identity of the tutor affects the divergence of a self-referent phenotype-matching trait. We find that oblique learning (learning from unrelated individual of the previous generation) and maternal learning mask sexual selection and therefore do not allow the maintenance of divergence. In contrast, by enhancing positive frequency-dependent sexual selection, paternal learning can maintain more divergence than genetic inheritance, but leads to the loss of polymorphism more easily. Furthermore, paternal learning inhibits the invasion of a novel self-referent phenotype-matching trait, especially in a large population.

The effects of sexual selection on trait divergence in a peripheral population with gene flow

“…It thus becomes possible to better understand the causes of the underlying dynamics of more realistic, and hence more complicated, biological scenarios. In the phenotype matching model, we expect that biological phenomena that alter trait frequencies between males and females, such as sex‐specific selection or migration, may alter the equilibrium trait conditions, although analysis of the two‐island case shows that trait divergence still peaks at an intermediate preference strength with moderately different migration rates between the sexes (Yeh and Servedio, ). There are many different sexual selection scenarios that build upon the Fisherian preference/trait model that we use here, which has indeed been considered a “null model” for sexual selection (Prum ).…”

Geography, assortative mating, and the effects of sexual selection on speciation with gene flow

“…These forms of imprinting have the potential to behave very similarly to phenotype matching in both sympatric speciation (Verzijden et al 2005) and reinforcement ) models in certain cases. Maternal and paternal imprinting do, however, differ in several important properties, including in the fact that, under polygyny, paternal imprinting enhances the effects of sexual selection by leading to exaggerated preferences (Tramm and Servedio 2008); this can lead to interesting differences in the specifics of their effects on trait divergence (Verzijden et al 2005;Chaffee et al 2013;Yeh and Servedio 2015).…”

How phenotypic matching based on neutral mating cues enables speciation in locally adapted populations

“…Both sexual imprinting and Matchmaker can produce assortative mating, but despite extensive theoretical effort (reviewed in Butlin et al, ; Gavrilets, ; Gavrilets, ; Kopp et al, ; Yeh & Servedio, ), more analysis is needed of how these mate‐choice mechanisms affect speciation in the presence of local genetic adaptation to differing ecological niches. Servedio, Saether, and Saetre () analyzed the case where after allopatry hybrid matings have reduced fitness, and Yeh and Servedio () analyzed learning of self‐referent phenotype matching—a proxy for some types of sexual imprinting—and showed that divergence between populations can be maintained if traits are learnt from father, but the only way the cue can spread initially is if the cue is itself under natural selection, that is, is a magic trait. Magic‐trait mate choice is known to produce speciation in the presence of ecological divergence between niches (van Doorn, Edelaar, & Weissing, ; Kopp et al, ).…”

“…And given its potential importance, who do we expect to imprint on whom (Chaffee, Griffin, & Gilman, 2013;Verzijden et al, 2012;Yang, Servedio, & Richards-Zawacki, 2019;Yeh & Servedio, 2015)?…”