Open AccessEvolution of postzygotic reproductive isolation in galliform birds: analysis of first and second hybrid generations and backcrosses
Author(s) -
Arrieta Ramiro S.,
Lijtmaer Darío A.,
Tubaro Pablo L.
Publication year - 2013
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1111/bij.12153
Subject(s) - reproductive isolation , biology , hybrid , genetic algorithm , gene flow , evolutionary biology , hybrid zone , sterility , genetics , zoology , gene , genetic variation , population , botany , demography , sociology
The process of speciation is a crucial aspect of evolutionary biology. In this study, we analysed the patterns of evolution of postzygotic reproductive isolation in Galliformes using information on hybridization and genetic distance among species. Four main patterns arose: (1) hybrid inviability and sterility in F 1 hybrids increase as species diverge; (2) the presence of geographical overlap does not affect the evolution of postzygotic isolation; (3) the galliforms follow Haldane's rule; (4) hybrid inviability is higher in F 2 than in F 1 hybrids, but does not appear to be increased in the backcrosses. This study contributes to the growing evidence suggesting that the patterns of evolution of postzygotic isolation and the process of speciation are shared among avian groups (and animals in general). In particular, our results support the notion of F 2 hybrid inviability as being key for the maintenance of species genetic integrity when prezygotic isolation barriers are overcome in closely related species, in which postzygotic isolation in the F 1 hybrid might still not be fully developed. To the contrary, hybrids from backcrosses did not show serious inviability problems (at least not more than F 1 hybrids), demonstrating that they could generate gene flow among bird species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society , 2013, 110 , 528–542.