title: Spatial sorting promotes the spread of maladaptive hybridization.
abstract: Invasive hybridization is causing loss of biodiversity worldwide. The spread of such introgression can occur even when hybrids have reduced Darwinian fitness, which decreases the frequency of hybrids due to low survival or reproduction through time. This paradox can be partially explained by spatial sorting, where genotypes associated with dispersal increase in frequency at the edge of expansion, fueling further expansion and allowing invasive hybrids to increase in frequency through space rather than time. Furthermore, because all progeny of a hybrid will be hybrids (i.e., will possess genes from both parental taxa), nonnative admixture in invaded populations can increase even when most hybrid progeny do not survive. Broader understanding of spatial sorting is needed to protect native biodiversity.
authors.affiliation: Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA. Electronic address: winsor.lowe@umontana.edu.
authors.forename: Winsor H
authors.initials: WH
authors.lastname: Lowe
authors.affiliation: US Geological Survey, Northern Rocky Mountain Science Center, Glacier National Park, West Glacier, MT 59936, USA; Flathead Lake Biological Station, University of Montana, Polson, MT 59860, USA.
authors.forename: Clint C
authors.initials: CC
authors.lastname: Muhlfeld
authors.affiliation: Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
authors.forename: Fred W
authors.initials: FW
authors.lastname: Allendorf
mesh_terms: D000220:Adaptation, Biological; D063147:Animal Distribution; D000818:Animals; D003247:Conservation of Natural Resources; D056084:Genetic Fitness; D006824:Hybridization, Genetic; D058865:Introduced Species; D013037:Spatial Behavior
keywords: biodiversity; conservation; dispersal; evolution; introgression; invasive species