title: Unraveling cryptic reticulate relationships and the origin of orphan hybrid disjunct populations in Narcissus.
abstract: Evolutionary consequences of natural hybridization between species may vary so drastically depending on spatial, genetic, and ecological factors that multiple approaches are required to uncover them. To unravel the evolutionary history of a controversial hybrid (Narcissus x perezlarae), here we use four approaches: DNA sequences from five regions (four organellar, one nuclear), cytological studies (chromosome counts and genome size), crossing experiments, and niche modeling. We conclude that (1) it actually consists of two different hybrid taxa, N.xperezlarae s.s. (N. cavanillesii x N. miniatus) and N.xalentejanus (N. cavanillesii x N. serotinus); (2) both have been formed several times independently, that is, polytopically; (3) N. cavanillesii was the mother progenitor in most hybridization events. We also address the origin of orphan hybrid populations of N.xperezlarae in eastern Spain, hundreds of kilometers away from N. cavanillesii. Although long-distance dispersal of already formed hybrids cannot be completely rejected, extirpation of N. cavanillesii via demographic competition is a more likely explanation. Low-reproductive barriers to fertilization by foreign pollen in N. cavanillesii, molecular footprints of the former presence of this species in the area, active asexual propagation by bulbs in N.xperezlarae, and overlapping ecological niches are consistent with the extirpation scenario.
authors.affiliation: Universidade de Lisboa. Museu Nacional de História Natural, Jardim Botânico, Rua da Escola Politécnica 58. 1280-102 Lisboa, Portugal. icmarques@fc.ul.pt
authors.forename: Isabel
authors.initials: I
authors.lastname: Marques
authors.forename: Gonzalo Nieto
authors.initials: GN
authors.lastname: Feliner
authors.forename: David
authors.initials: D
authors.lastname: Draper Munt
authors.forename: Maria Amélia
authors.initials: MA
authors.lastname: Martins-Loução
authors.forename: Javier Fuertes
authors.initials: JF
authors.lastname: Aguilar
mesh_terms: D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D018745:Genome, Plant; D005838:Genotype; D006824:Hybridization, Genetic; D031427:Narcissus / Q000235:genetics*