title: Experimental evolution reveals balancing selection underlying coexistence of alternative male reproductive phenotypes.
abstract: Heritable alternative reproductive phenotypes (ARPs), which differ in traits associated with competition for mates, occur across taxa. If polymorphism in the genes underlying ARPs is maintained by balancing selection, selection should return ARP proportions to their equilibrium if that equilibrium is perturbed. Here, we used an experimental evolution approach to directly test this prediction in male Rhizoglyphus robini, in which two heritable morphs occur: armored fighters and more female-like, benign scramblers. Using selection lines nearly fixed for male morph, we constructed replicate populations consisting of 50% or 94% fighters, and allowed them to evolve for 14 generations in two types of environment: simple or spatially complex. We found that in both types of populations, the proportion of fighters converged on values within a narrow range of 0.70-0.83, although the rate of convergence was slower in the complex environment. Our results thus demonstrate balancing selection acting on polymorphism(s) underlying ARPs.
authors.affiliation: Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Skrzynecka
authors.affiliation: Evolutionary Ecology Group, Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614, Poznań, Poland. jradwan@amu.edu.pl.
authors.forename: Jacek
authors.initials: J
authors.lastname: Radwan
mesh_terms: D040041:Acaridae / Q000235:genetics* / Q000502:physiology; D000818:Animals; D019143:Evolution, Molecular; D005260:Female; D008297:Male; D052586:Mating Preference, Animal; D010641:Phenotype; D011110:Polymorphism, Genetic; D012641:Selection, Genetic
keywords: Alternative mating tactics; lek paradox; polymorphism; sexual selection