title: Genetic variation in nuclear and mitochondrial markers supports a large sex difference in lifetime reproductive skew in a lekking species.
abstract: Sex differences in skews of vertebrate lifetime reproductive success are difficult to measure directly. Evolutionary histories of differential skew should be detectable in the genome. For example, male-biased skew should reduce variation in the biparentally inherited genome relative to the maternally inherited genome. We tested this approach in lek-breeding ruff (Class Aves, Philomachus pugnax) by comparing genetic variation of nuclear microsatellites (θ n ; biparental) versus mitochondrial D-loop sequences (θ m ; maternal), and conversion to comparable nuclear (N e ) and female (N ef ) effective population size using published ranges of mutation rates for each marker (μ). We provide a Bayesian method to calculate N e (θ n = 4N e μ n ) and N ef (θ m = 2N ef μ m ) using 95% credible intervals (CI) of θ n and θ m as informative priors, and accounting for uncertainty in μ. In 96 male ruffs from one population, N e was 97% (79-100%) lower than expected under random mating in an ideal population, where N e :N ef = 2. This substantially lower autosomal variation represents the first genomic support of strong male reproductive skew in a lekking species.
authors.affiliation: Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen PO Box 11103, Groningen, 9700 CC, the Netherlands ; Department of Natural History, Royal Ontario Museum 100 Queen's Park Crescent, Toronto, M5S 2C6, Ontario, Canada.
authors.forename: Yvonne I
authors.initials: YI
authors.lastname: Verkuil
authors.affiliation: Department of Natural History, Royal Ontario Museum 100 Queen's Park Crescent, Toronto, M5S 2C6, Ontario, Canada.
authors.forename: Cedric
authors.initials: C
authors.lastname: Juillet
authors.affiliation: Department of Biological Sciences, Simon Fraser University Burnaby, V5A 1S6, British Columbia, Canada.
authors.forename: David B
authors.initials: DB
authors.lastname: Lank
authors.affiliation: Department of Fish, Wildlife and Environmental Studies, Swedish University of Agricultural Sciences Umeå, SE- 901 83, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Widemo
authors.affiliation: Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen PO Box 11103, Groningen, 9700 CC, the Netherlands ; Department of Marine Ecology, NIOZ Royal Netherlands Institute for Sea Research PO Box 59, Den Burg, Texel, 1790 AB, the Netherlands.
authors.forename: Theunis
authors.initials: T
authors.lastname: Piersma
keywords: Effective population size; Philomachus pugnax; ruff; sexual selection; shorebirds