title: Invasions and extinctions through the looking glass of evolutionary ecology.
abstract: Invasive and endangered species reflect opposite ends of a spectrum of ecological success, yet they experience many similar eco-evolutionary challenges including demographic bottlenecks, hybridization and novel environments. Despite these similarities, important differences exist. Demographic bottlenecks are more transient in invasive species, which (i) maintains ecologically relevant genetic variation, (ii) reduces mutation load, and (iii) increases the efficiency of natural selection relative to genetic drift. Endangered species are less likely to benefit from admixture, which offsets mutation load but also reduces fitness when populations are locally adapted. Invading species generally experience more benign environments with fewer natural enemies, which increases fitness directly and also indirectly by masking inbreeding depression. Adaptive phenotypic plasticity can maintain fitness in novel environments but is more likely to evolve in invasive species encountering variable habitats and to be compromised by demographic factors in endangered species. Placed in an eco-evolutionary context, these differences affect the breadth of the ecological niche, which arises as an emergent property of antagonistic selection and genetic constraints. Comparative studies of invasions and extinctions that apply an eco-evolutionary perspective could provide new insights into the environmental and genetic basis of ecological success in novel environments and improve efforts to preserve global biodiversity.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'.
authors.affiliation: Department of Biology, Queen's University, 116 Barrie Street, Kingston, Ontario, Canada K7L 3N6 robert.colautti@queensu.ca.
authors.forename: Robert I
authors.identifier: 0000-0003-4213-0711
authors.initials: RI
authors.lastname: Colautti
authors.affiliation: Institute of Integrative Biology, Department of Environmental Systems Science, ETH Zurich, Universitätsstrasse 16, 8092 Zürich, Switzerland.
authors.forename: Jake M
authors.identifier: 0000-0003-2226-7913
authors.initials: JM
authors.lastname: Alexander
authors.affiliation: Department of Ecology and Evolutionary Biology, University of Arizona, PO Box 210088, Tucson, AZ 85721, USA.
authors.forename: Katrina M
authors.identifier: 0000-0002-7302-6637
authors.initials: KM
authors.lastname: Dlugosch
authors.affiliation: Department of Plant Biology, University of Vermont, 111 Jeffords Hall, Burlington, VT 05405, USA.
authors.forename: Stephen R
authors.identifier: 0000-0001-8887-9213
authors.initials: SR
authors.lastname: Keller
authors.affiliation: Department of Biology, Wesleyan University, 237 Church Street, Middletown, CT 06459, USA.
authors.forename: Sonia E
authors.identifier: 0000-0001-8815-6437
authors.initials: SE
authors.lastname: Sultan
mesh_terms: D005075:Biological Evolution; D017753:Ecosystem; D056727:Endangered Species; D053476:Extinction, Biological; D014644:Genetic Variation; D058865:Introduced Species; D010641:Phenotype
keywords: endangered species; epigenetics; evolutionary genetics; niche theory; plasticity; range limits