title: Floral colours in a world without birds and bees: the plants of Macquarie Island.
abstract: We studied biotically pollinated angiosperms on Macquarie Island, a remote site in the Southern Ocean with a predominately or exclusively dipteran pollinator fauna, in an effort to understand how flower colour affects community assembly. We compared a distinctive group of cream-green Macquarie Island flowers to the flora of likely source pools of immigrants and to a continental flora from a high latitude in the northern hemisphere. We used both dipteran and hymenopteran colour models and phylogenetically informed analyses to explore the chromatic component of community assembly. The species with cream-green flowers are very restricted in colour space models of both fly vision and bee vision and represent a distinct group that plays a very minor role in other communities. It is unlikely that such a community could form through random immigration from continental source pools. Our findings suggest that fly pollination has imposed a strong ecological filter on Macquarie Island, favouring floral colours that are rare in continental floras. This is one of the strongest demonstrations that plant-pollinator interactions play an important role in plant community assembly. Future work exploring colour choices by dipteran flower visitors would be valuable.
authors.affiliation: School of Media and Communication, RMIT University, Melbourne, Vic., Australia.|Faculty of Information Technology, Monash University, Melbourne, Vic., Australia.
authors.forename: M
authors.initials: M
authors.lastname: Shrestha
authors.affiliation: Institut für Sinnesökologie, Department Biologie, Heinrich-Heine Universität Düsseldorf, Düsseldorf, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Lunau
authors.affiliation: Faculty of Information Technology, Monash University, Melbourne, Vic., Australia.
authors.forename: A
authors.initials: A
authors.lastname: Dorin
authors.affiliation: Institut für Sinnesökologie, Department Biologie, Heinrich-Heine Universität Düsseldorf, Düsseldorf, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Schulze
authors.affiliation: Chemical Plant Ecology, University Darmstadt, Darmstadt, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bischoff
authors.affiliation: School of Biological Sciences, Monash University, Melbourne, Vic., Australia.
authors.forename: M
authors.initials: M
authors.lastname: Burd
authors.affiliation: School of Media and Communication, RMIT University, Melbourne, Vic., Australia.|Department of Physiology, Monash University, Melbourne, Vic., Australia.
authors.forename: A G
authors.initials: AG
authors.lastname: Dyer
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology; D001717:Birds / Q000502:physiology; D003116:Color; D004175:Diptera / Q000502:physiology*; D035264:Flowers / Q000033:anatomy & histology* / Q000235:genetics / Q000502:physiology; D005843:Geography; D062312:Islands; D019684:Magnoliopsida / Q000033:anatomy & histology* / Q000235:genetics / Q000502:physiology; D008954:Models, Biological; D010802:Phylogeny; D054817:Pollination; D013648:Tasmania
keywords: Chromatic signal; floral colour; fly pollination; hoverfly (Eristalis); sub-Antarctic island