title: Avian mothers create different phenotypes by hormone deposition in their eggs.
abstract: An increasing number of studies in a variety of taxa demonstrate the role of maternal sex steroids on offspring development. In avian species, mothers deposit substantial amounts of androgens in their eggs, and experimental evidence indicates that these maternal androgens influence the chick's early development. Despite the well-known organizing role of sex steroids on brain and behaviour, studies on avian maternal egg hormones almost exclusively focus on the chick phase. Here, we show experimentally that in Black-headed gulls maternal androgens in the egg enhance the development of the nuptial plumage and the frequency of aggressive and sexual displays almost 1 year after hatching. We conclude that maternal sex steroids may be a key factor for the determination of subtle but important individual differences within the same sex and species, which may have important consequences for Darwinian fitness and evolutionary processes.
authors.affiliation: Behavioural Biology, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands. ceising@botzoo.uct.ac.za
authors.forename: Corine M
authors.initials: CM
authors.lastname: Eising
authors.forename: Wendt
authors.initials: W
authors.lastname: Müller
authors.forename: Ton G G
authors.initials: TG
authors.lastname: Groothuis
mesh_terms: D000728:Androgens / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D046091:Charadriiformes / Q000033:anatomy & histology* / Q000254:growth & development*; D005241:Feathers / Q000254:growth & development*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000502:physiology; D008425:Maternal Behavior; D009035:Mothers; D010063:Ovum / Q000187:drug effects / Q000254:growth & development*; D010641:Phenotype
chemical_list: D000728:Androgens; D012739:Gonadal Steroid Hormones