Floral colours in a world without birds and bees:the plants of Macquarie Island

• Published in: Plant Biology
• Main Authors: Shrestha, M., Lunau, K., Dorin, A., Schulze, B., Bischoff, M., Burd, M., Dyer, A. G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: Chromatic signal; floral colour; fly pollination; hoverfly (Eristalis); sub-Antarctic island; Antarc*; Antarctic; Macquarie Island; Southern Ocean
• Online Access: https://pure.uhi.ac.uk/en/publications/e51bb725-18e1-4bbf-a434-af6a82bb2b58; https://doi.org/10.1111/plb.12456; http://www.scopus.com/inward/record.url?scp=85027956562&partnerID=8YFLogxK; http://www.scopus.com/inward/citedby.url?scp=85027956562&partnerID=8YFLogxK

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.