title: Mandible shape in hybrid mice.
abstract: Hybridisation between closely related species is frequently seen as retarding evolutionary divergence and can also promote it by creating novel phenotypes due to new genetic combinations and developmental interactions. We therefore investigated how hybridisation affects the shape of the mouse mandible, a well-known feature in evo-devo studies. Parental groups corresponded to two strains of the European mouse sub-species Mus musculus domesticus and Mus musculus musculus. Parents and hybrids were bred in controlled conditions. The mandibles of F(1) hybrids are mostly intermediate between parental phenotypes as expected for a complex multigenic character. Nevertheless, a transgressive effect as well as an increased phenotypic variance characterise the hybrids. This suggests that hybridisation between the two subspecies could lead to a higher phenotypic variance due to complex interactions among the parental genomes including non-additive genetic effects. The major direction of variance is conserved, however, among hybrids and parent groups. Hybridisation may thus play a role in the production of original transgressive phenotypes occurring following pre-existing patterns of variance.
authors.affiliation: Paléoenvironnement et Paléobiosphère, UMR 5125 CNRS, Université Lyon 1, Bâtiment Géode, 2 Rue Dubois, Campus de la Doua, 69622 Villeurbanne Cedex, France. Sabrina.Renaud@univ-lyon1.fr
authors.forename: Sabrina
authors.initials: S
authors.lastname: Renaud
authors.forename: Paul
authors.initials: P
authors.lastname: Alibert
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Auffray
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D003433:Crosses, Genetic; D005260:Female; D005583:Fourier Analysis; D008297:Male; D008334:Mandible / Q000033:anatomy & histology*; D051379:Mice / Q000033:anatomy & histology* / Q000235:genetics; D009929:Organ Size; D010641:Phenotype