Fig. 1: Conceptual diagram describing compensatory genomic coadaptation in silent Hawaiian crickets.
a Feedback loops between an adaptive variant under selection, flatwing, and genome architecture. A population containing only normal singing Teleogryllus oceanicus males is subject to strong selection from lethal, acoustically-orienting parasitoid, Ormia ochracea (left). Flatwing invades the genome and quickly spreads under selection (middle shaded box; pink star represents the flatwing genomic variant). The spread of flatwing has phenotypic effects that are directly selected due to the adaptive benefit of parasitoid avoidance (right, top arrow). However, flatwing also imposes direct fitness costs via pleiotropic or other associated effects, for example through a diminished ability to attract mates (right, bottom arrow, represented by pink-coloured cricket. Deleterious effects might also arise due to genomic hitchhiking, represented by the purple-shaded DNA strands. See Main Text for examples of direct fitness costs.) The presence of flatwing in the population gene pool also imposes a changed regime of social selection by altering the perceived social environment (right, middle arrow, translucent pink crickets represent the inability of focal individuals to evaluate the presence of potential mates or rivals, due to disrupted communication. See Main Text for examples of indirect social effects.) Pre-existing adaptive plasticity can mitigate negative direct and indirect fitness effects of flatwing (bottom grey dashed arrow), but these negative consequences also generate a selection that feeds back to favour genetically-encoded secondary adaptations or epistatic allelic combinations that reduce negative effects of flatwing (orange arrow). Such genomic coadaptation has rarely been studied, while considerable research attention has been directed towards understanding the former process. b Timeline of key social environment transitions in the Kauai cricket population (based on information from28,29,31,32,152,153. Colour-coding of years matches that used in figures throughout this manuscript.
