Repository logo

Facilitation and competition shape a geographical mosaic of flower colour polymorphisms

Accepted version

No Thumbnail Available



Change log


jats:titleAbstract</jats:title>jats:p jats:list

jats:list-itemjats:pFlower colour differs dramatically between populations for some plant species; yet, we know little about what drives this variation. Such polymorphisms can be influenced by plant–pollinator interactions, but whether they are also influenced by pollinator‐mediated plant–plant interactions is unknown.</jats:p></jats:list-item>

jats:list-itemjats:pWe test whether flower colour polymorphisms can arise through convergence (facilitation) or divergence (competition) of flower phenotypes resulting from plant–plant interactions mediated by the shared, and only, pollinator (orange‐breasted sunbird) of 10 jats:italicErica</jats:italic> communities in South Africa.</jats:p></jats:list-item>

jats:list-itemjats:pSunbird visitation rates to the less‐preferred jats:italicErica</jats:italic> species in communities increased with colour similarity to the most‐visited species, suggesting that polymorphisms can be maintained by selection for colour convergence within communities, which promotes shared signals through rewarding mimicry (i.e. facilitation).</jats:p></jats:list-item>

jats:list-itemjats:pColour similarity was lowest when risk of reproductive interference was greatest: that is, when reproductive morphology (stigma–anther distance) and flowering phenology was most similar, and when floral density differed greatly between species. This implies that polymorphisms can also be maintained by selection for colour divergence, since this promotes assortative pollinator foraging (i.e. competition).</jats:p></jats:list-item>

jats:list-itemjats:pDifferent populations of a species may experience opposite selective pressures, depending on their community context. This is the first evidence that a geographic mosaic of plant–plant pollination interactions could maintain colour polymorphisms in congeneric species sharing a single pollinator.</jats:p></jats:list-item> </jats:list> </jats:p>jats:pA free <jats:ext-link xmlns:xlink="" xlink:href="">Plain Language Summary</jats:ext-link> can be found within the Supporting Information of this article.</jats:p>



character displacement, flowering phenology, interspecific pollen transfer, mimicry rings, Nectariniidae, reproductive interference

Journal Title

Functional Ecology

Conference Name

Journal ISSN


Volume Title





All rights reserved
Biotechnology and Biological Sciences Research Council (BB/J014109/1)