On the capacity for rapid adaptation and plastic responses to herbivory and intraspecific competition in insular populations of Plectritis congesta

Abstract

A capacity for rapid adaptation should enhance the persistence of populations subject to temporal and spatial heterogeneity in natural selection, but examples from nature remain scarce. Plectritis congesta (Caprifoliaceae) is a winter annual that exhibits local adaptation to browsing by ungulates and hypothesized to show context-dependent trade-offs in traits affecting success in competition versus resistance or tolerance to browsing. We grew P. congesta from 44 insular populations historically exposed or naïve to ungulates in common gardens to (1) quantify genetic, plastic and competitive effects on phenotype; (2) estimate a capacity for rapid adaptation (evolvability); and (3) test whether traits favoured by selection with ungulates present were selected against in their absence. Plants from browsed populations bolted and flowered

Adaptation to climate change through seasonal migration revealed by climatic versus demographic niche models

“…However, because doing so will add assumptions that may be challenging to test, we advise that comparative analysis, external validations (this study), and adaptive management (Walters, 1986) offer more direct paths to reliable knowledge in conservation planning (e.g., Romesburg, 1981). Our models also assumed niche conservatism, whereas capacities for rapid adaptation are increasingly being reported in nature (e.g., Bonnet et al, 2022; Hendry et al, 2018; Radchuk et al, 2019; Skaien & Arcese, 2022), including via gene flow and directional selection in song sparrows (Mikles et al, 2020; Reid & Arcese, 2020; Reid et al, 2021; Walsh et al, 2019). Initial findings imply that a relatively small number of loci influence osmoregulation and body size (Carbeck et al unpubl.…”

“…Our models also assumed niche conservatism, whereas capacities for rapid adaptation are increasingly being reported in nature (e.g., Bonnet et al, 2022;Hendry et al, 2018;Radchuk et al, 2019;Skaien & Arcese, 2022), including via gene flow and directional selection in song sparrows (Mikles et al, 2020;Reid & Arcese, 2020;Reid et al, 2021;Walsh et al, 2019). Initial findings imply that a relatively small number of loci influence osmoregulation and body size (Carbeck et al unpubl.…”