title: Reproductive dynamics shapes genomotype composition in an allopolyploid complex.
abstract: Hybrid complexes are composed of organisms with multiple combinations of parental genomes (genomotypes) that interconnect through nets of crosses. Although several such complexes are well established without speciation or extinction, mechanisms shaping their dynamics remain poorly understood. In this study, we quantified the reproductive success of the allopolyploid Iberian fish Squalius alburnoides in experimental free-access and directional crosses involving the most common genomotypes. Specifically, we analysed the paternity of the offspring produced when females had free access to male genomotypes and quantified variations in egg allocation, fertilization rate, and offspring survival among crosses involving each male genomotype. The composition of the offspring produced from free-access crosses varied significantly from that expected from random mating, suggesting that offspring production and viability are not independent of parental male genomotype. Moreover, directional crosses producing the genomotype most commonly found in wild populations appeared to be the most successful, with females laying more eggs, and fertilization rate and offspring survival being the highest. These results suggest that reproductive dynamics plays a relevant role in structuring the genomotype composition of populations and opens a path to future research on the ecology and evolutionary biology of allopolyploids and their multiplicity of possible evolutionary pathways.
authors.affiliation: Centro de Ecologia, Evolução e Alterações Ambientais (cE3c), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal mfsantos@fc.ul.pt.
authors.forename: M
authors.identifier: 0000-0002-0808-5198
authors.initials: M
authors.lastname: Morgado-Santos
authors.affiliation: Centro de Ecologia, Evolução e Alterações Ambientais (cE3c), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
authors.forename: S
authors.identifier: 0000-0003-3882-2360
authors.initials: S
authors.lastname: Carona
authors.affiliation: Centro de Ecologia, Evolução e Alterações Ambientais (cE3c), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
authors.forename: M F
authors.identifier: 0000-0001-7308-2279
authors.initials: MF
authors.lastname: Magalhães
authors.affiliation: Centro de Filosofia das Ciências da Universidade de Lisboa (CFCUL), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
authors.forename: L
authors.initials: L
authors.lastname: Vicente
authors.affiliation: Centro de Ecologia, Evolução e Alterações Ambientais (cE3c), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
authors.forename: M J
authors.identifier: 0000-0002-8081-9539
authors.initials: MJ
authors.lastname: Collares-Pereira
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000235:genetics / Q000502:physiology*; D005260:Female; D016678:Genome; D005838:Genotype; D008297:Male; D011157:Population Dynamics; D012098:Reproduction; D012641:Selection, Genetic
keywords: directional crosses; egg allocation; fertilization rate; free-access crosses; offspring survival; paternity analysis