title: Deleterious mutations can surf to high densities on the wave front of an expanding population.
abstract: There is an increasing recognition that evolutionary processes play a key role in determining the dynamics of range expansion. Recent work demonstrates that neutral mutations arising near the edge of a range expansion sometimes surf on the expanding front leading them rather than that leads to reach much greater spatial distribution and frequency than expected in stationary populations. Here, we extend this work and examine the surfing behavior of nonneutral mutations. Using an individual-based coupled-map lattice model, we confirm that, regardless of its fitness effects, the probability of survival of a new mutation depends strongly upon where it arises in relation to the expanding wave front. We demonstrate that the surfing effect can lead to deleterious mutations reaching high densities at an expanding front, even when they have substantial negative effects on fitness. Additionally, we highlight that this surfing phenomenon can occur for mutations that impact reproductive rate (i.e., number of offspring produced) as well as mutations that modify juvenile competitive ability. We suggest that these effects are likely to have important consequences for rates of spread and the evolution of spatially expanding populations.
authors: Zoology Building, School of Biological Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen, AB24 2TZ Scotland, UK. justin.travis@abdn.ac.uk
authors: Justin M J
authors: JM
authors: Travis
authors: Tamara
authors: T
authors: Münkemüller
authors: Olivia J
authors: OJ
authors: Burton
authors: Alex
authors: A
authors: Best
authors: Calvin
authors: C
authors: Dytham
authors: Karin
authors: K
authors: Johst
mesh_terms: D000818:Animals; D005075:Biological Evolution; D005060:Europe; D005828:Genetics, Population; D006801:Humans; D009154:Mutation; D011157:Population Dynamics; D044382:Population Groups / Q000235:genetics*