title: Pleistocene distribution range shifts were accompanied by breeding system divergence within Hornungia alpina (Brassicaceae) in the Alps.
abstract: Impact of glacial history on the phylogeography of silicate-dwelling plants of the European Alps has been particularly well studied, whereas virtually no data are available for species growing on different bedrock types, as for Hornungia alpina. Bayesian clustering of AFLP data only partly support the distinction of three subspecies as morphologically defined. Whereas the phylogeographical N-group corresponds to subsp. alpina, the congruence of the SW-group and SE-group with subsp. brevicaulis, and subsp. austroalpina, respectively, is limited. High levels of rarity and genetic diversity in the N-group suggest Pleistocene survival along the outer margin of the Alpine arc. For subsp. brevicaulis we suggest a single origin from a refugium in the Southwestern Alps, whereas subsp. austroalpina might have originated twice in the Southern and Southeastern Alps. Different levels of genetic diversity and partitioning of genetic variation indicate a divergence in breeding system, which is corroborated by pollinator exclusion experiments revealing self-incompatibility in the N-group and autonomous selfing in the SE-group.
authors.affiliation: Department of Biogeography and Botanical Garden, University of Vienna, Rennweg 14, A-1030 Vienna, Austria. manuela.winkler@boku.ac.at
authors.forename: Manuela
authors.initials: M
authors.lastname: Winkler
authors.forename: Andreas
authors.initials: A
authors.lastname: Tribsch
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Paun
authors.forename: Thorsten
authors.initials: T
authors.lastname: Englisch
authors.forename: Peter
authors.initials: P
authors.lastname: Schönswetter
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D001499:Bayes Theorem; D019607:Brassicaceae / Q000145:classification / Q000235:genetics*; D016000:Cluster Analysis; D018744:DNA, Plant / Q000235:genetics; D017753:Ecosystem; D005060:Europe; D014644:Genetic Variation; D005843:Geography; D010802:Phylogeny; D025341:Principal Component Analysis; D012098:Reproduction / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant