title: North African hybrid sparrows (Passer domesticus, P. hispaniolensis) back from oblivion - ecological segregation and asymmetric mitochondrial introgression between parental species.
abstract: A stabilized hybrid form of the house sparrow (Passer domesticus) and the Spanish sparrow (P. hispaniolensis) is known as Passer italiae from the Italian Peninsula and a few Mediterranean islands. The growing attention for the Italian hybrid sparrow and increasing knowledge on its biology and genetic constitution greatly contrast the complete lack of knowledge of the long-known phenotypical hybrid sparrow populations from North Africa. Our study provides new data on the breeding biology and variation of mitochondrial DNA in three Algerian populations of house sparrows, Spanish sparrows, and phenotypical hybrids. In two field seasons, the two species occupied different breeding habitats: Spanish sparrows were only found in rural areas outside the cities and bred in open-cup nests built in large jujube bushes. In contrast, house sparrows bred only in the town centers and occupied nesting holes in walls of buildings. Phenotypical hybrids were always associated with house sparrow populations. House sparrows and phenotypical hybrids started breeding mid of March, and most pairs had three successive clutches, whereas Spanish sparrows started breeding almost one month later and had only two successive clutches. Mitochondrial introgression is strongly asymmetric because about 75% of the rural Spanish sparrow population carried house sparrow haplotypes. In contrast, populations of the Italian hybrid form, P. italiae, were genetically least diverse among all study populations and showed a near-fixation of house sparrow haplotypes that elsewhere were extremely rare or that were even unique for the Italian Peninsula. Such differences between mitochondrial gene pools of Italian and North African hybrid sparrow populations provide first evidence that different demographic histories have shaped the extant genetic diversity observed on both continents.
authors.affiliation: Faculty of Sciences of nature and lifes Department of Agropastoralism University of Djelfa BP. 3117 17000 Djelfa Algeria.
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Ait Belkacem
authors.affiliation: Senckenberg Naturhistorische Sammlungen Königsbrücker Landstraße 159D-01109 Dresden Germany; Institute of Vertebrate Biology Czech Academy of Sciences External Research Facility Studenec Studenec 122675 02 Koněšín Czech Republic.
authors.forename: Oliver
authors.initials: O
authors.lastname: Gast
authors.affiliation: Senckenberg Naturhistorische Sammlungen Königsbrücker Landstraße 159 D-01109 Dresden Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Stuckas
authors.affiliation: Department of Evolutionary Ecology Estación Biológica de Doñana - CSIC Avda. Américo Vespucio s/n 41092 Seville Spain.
authors.forename: David
authors.initials: D
authors.lastname: Canal
authors.affiliation: Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche Via Archirafi 18 I-90123 Palermo Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: LoValvo
authors.affiliation: Cooperativa Silene Via Dondes Regio, 8/a 90127 Palermo Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Giacalone
authors.affiliation: Senckenberg Naturhistorische Sammlungen Königsbrücker Landstraße 159 D-01109 Dresden Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Päckert
keywords: Agricultural landscape mosaic; Algeria; NADH dehydrogenase; breeding phenology; nest site choice