title: Paternity analysis reveals wide pollen dispersal and high multiple paternity in a small isolated population of the bird-pollinated Eucalyptus caesia (Myrtaceae).
abstract: Optimal foraging behaviour by nectavores is expected to result in a leptokurtic pollen dispersal distribution and predominantly near-neighbour mating. However, complex social interactions among nectarivorous birds may result in different mating patterns to those typically observed in insect-pollinated plants. Mating system, realised pollen dispersal and spatial genetic structure were examined in the bird-pollinated Eucalyptus caesia, a species characterised by small, geographically disjunct populations. Nine microsatellite markers were used to genotype an entire adult stand and 181 seeds from 28 capsules collected from 6 trees. Mating system analysis using MLTR revealed moderate to high outcrossing (tm=0.479-0.806) and low estimates of correlated paternity (rp=0.136±s.e. 0.048). Paternity analysis revealed high outcrossing rates (mean=0.72) and high multiple paternity, with 64 different sires identified for 181 seeds. There was a significant negative relationship between the frequency of outcross mating and distance between mating pairs. Realised mating events were more frequent than expected with random mating for plants <40 m apart. The overall distribution of pollen dispersal distances was platykurtic. Despite extensive pollen dispersal within the stand, three genetic clusters were detected by STRUCTURE analysis. These genetic clusters were strongly differentiated yet geographically interspersed, hypothesised to be a consequence of rare recruitment events coupled with extreme longevity. We suggest that extensive polyandry and pollen dispersal is a consequence of pollination by highly mobile honeyeaters and may buffer E. caesia against the loss of genetic diversity predicted for small and genetically isolated populations.
authors.affiliation: School of Plant Biology, The University of Western Australia, Crawley, Western Australia, Australia.|Botanic Gardens and Parks Authority, Fraser Avenue, Kings Park and Botanic Garden, West Perth, Western Australia, Australia.|Centre of Excellence in Natural Resource Management, The University of Western Australia, Albany, Western Australia, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Bezemer
authors.affiliation: School of Plant Biology, The University of Western Australia, Crawley, Western Australia, Australia.|Botanic Gardens and Parks Authority, Fraser Avenue, Kings Park and Botanic Garden, West Perth, Western Australia, Australia.
authors.forename: S L
authors.initials: SL
authors.lastname: Krauss
authors.affiliation: Botanic Gardens and Parks Authority, Fraser Avenue, Kings Park and Botanic Garden, West Perth, Western Australia, Australia.|Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, Australian Capital Territory, Australia.
authors.forename: R D
authors.initials: RD
authors.lastname: Phillips
authors.affiliation: Botanic Gardens and Parks Authority, Fraser Avenue, Kings Park and Botanic Garden, West Perth, Western Australia, Australia.|Centre of Excellence in Natural Resource Management, The University of Western Australia, Albany, Western Australia, Australia.
authors.forename: D G
authors.initials: DG
authors.lastname: Roberts
authors.affiliation: School of Plant Biology, The University of Western Australia, Crawley, Western Australia, Australia.|Centre of Excellence in Natural Resource Management, The University of Western Australia, Albany, Western Australia, Australia.
authors.forename: S D
authors.initials: SD
authors.lastname: Hopper
mesh_terms: D000818:Animals; D001717:Birds; D005052:Eucalyptus / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D018895:Microsatellite Repeats; D011058:Pollen / Q000235:genetics*; D054817:Pollination; D012639:Seeds / Q000235:genetics