title: Contact zones: natural labs for studying evolutionary transitions.
abstract: Contrasts between related diploid and polyploid taxa can serve as windows into the evolution of sexual systems. A recent study of a moving diploid-polyploid contact zone explores this topic in novel ways.
authors.affiliation: Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK. c.lexer@kew.org
authors.forename: Christian
authors.initials: C
authors.lastname: Lexer
authors.forename: Marcela
authors.initials: M
authors.lastname: van Loo
mesh_terms: D005075:Biological Evolution; D017753:Ecosystem; D019665:Euphorbiaceae / Q000502:physiology*; D006824:Hybridization, Genetic; D011058:Pollen / Q000502:physiology; D011123:Polyploidy; D012098:Reproduction / Q000502:physiology; D013030:Spain