Hyper-specialization for long-billed bird pollination in a guild of South African plants: the Malachite Sunbird pollination syndrome
dc.contributor.author | Geerts S. | |
dc.contributor.author | Pauw A. | |
dc.date.accessioned | 2011-05-15T15:54:48Z | |
dc.date.available | 2011-05-15T15:54:48Z | |
dc.date.issued | 2009 | |
dc.description.abstract | A large diversity of floral morphological types exists within the bird pollination syndrome in the Cape Floral Region of South Africa. Here we focus on species with tubular flowers and ask: "Do differences in tube length among plant species correspond to differences in bill length among the birds that serve as pollinators?" To answer this question, we observed 1669 bird-plant interactions at thirteen bird-pollinated plant species across a spectrum of tube lengths. Only three nectar feeding bird species pollinated the focal plant species. The relatively short-billed species were the Southern Double-collared Sunbird (Cinnyris chalybea) and Orange-breasted Sunbird (Anthobaphes violacea); the only long-billed species was the Malachite Sunbird (Nectarinia famosa). We found that the groups of plant species pollinated by the long- and short-billed birds differed significantly in floral tube length. Short-billed sunbirds nevertheless often robbed long-tubed flowers by piercing the corolla, and there was a significant difference in floral tube length among those species that were robbed, and those that were pollinated by short-billed sunbirds. The presence of territorial Malachite Sunbirds depressed robbing rates by short-billed sunbirds at long-tubed flowers. In turn, the absence of Malachite Sunbirds from short-tubed plant species might be explained by the observed positive correlation between tube length and nectar volume. Together, these data suggest that there is a subset of the bird-pollinated plants at the Cape that are pollinated solely by the long-billed Malachite Sunbird, a pollination service irreplaceable by the more abundant, short-billed sunbird species. To extrapolate this finding to a greater subset of species in the Cape Floral Region, we measured flowers on herbarium specimens of all tubular putatively bird-pollinated plants. We find that floral tube length has a bimodal distribution with 37 Cape species potentially dependent on pollination by Malachite Sunbirds. © 2009 SAAB. | |
dc.description.version | Article | |
dc.identifier.citation | South African Journal of Botany | |
dc.identifier.citation | 75 | |
dc.identifier.citation | 4 | |
dc.identifier.issn | 2546299 | |
dc.identifier.other | 10.1016/j.sajb.2009.08.001 | |
dc.identifier.uri | http://hdl.handle.net/10019.1/9409 | |
dc.subject | flower visiting | |
dc.subject | guild | |
dc.subject | herbarium | |
dc.subject | morphology | |
dc.subject | nectarivory | |
dc.subject | passerine | |
dc.subject | plant-pollinator interaction | |
dc.subject | robbing | |
dc.subject | specialization | |
dc.subject | sugar | |
dc.subject | Africa | |
dc.subject | South Africa | |
dc.subject | Southern Africa | |
dc.subject | Sub-Saharan Africa | |
dc.subject | Aves | |
dc.subject | Nectarinia chalybea | |
dc.subject | Nectarinia famosa | |
dc.title | Hyper-specialization for long-billed bird pollination in a guild of South African plants: the Malachite Sunbird pollination syndrome | |
dc.type | Article |