title: Botany: specialized bird perch aids cross-pollination.
abstract: Birds may hover over or perch on flowers when feeding on nectar, and this assists cross-pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic 'rat's tail' plant (Babiana ringens, Iridaceae), whose function--unlike in other bird-pollinated plants--is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the cross-pollination of its unusual ground-level flowers.
authors.affiliation: School of Botany and Zoology, University of KwaZulu-Natal, Private Bag X01, Scottsville, Pietermaritzburg 3209, South Africa.
authors.forename: Bruce
authors.initials: B
authors.lastname: Anderson
authors.forename: William W
authors.initials: WW
authors.lastname: Cole
authors.forename: Spencer C H
authors.initials: SC
authors.lastname: Barrett
mesh_terms: D000818:Animals; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D005518:Food Preferences; D027621:Iridaceae / Q000033:anatomy & histology* / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D010788:Photosynthesis; D011058:Pollen / Q000502:physiology*; D012098:Reproduction / Q000502:physiology; D012727:Sex Characteristics; D020308:Songbirds / Q000502:physiology*; D013019:South Africa