Abstract Detail

Botany 2015 Colloquium: Integrated perspectives on the ecology, genetics and coevolution of intimate mutualisms

Armbruster, W. Scott [1], Wege, Juliet [2], Evans, Sian [3], Forest, Felix [4].

Evolution of Ecologically Generalized Pollination through Phenotypic Specialization and “Adaptive Behavior” of Stylidium flowers.

Phenotypic specialization of flowers (the evolution of highly derived floral morphologies) has generally been thought to be associated with ecological specialization on few pollinator species or functional groups. We question this perception as a result of our studies of the pollination ecology of triggerplants (Stylidium, Stylidiaceae), a plant with floral morphological and behavioral “specializations” that rival those of the most extreme orchid flowers. Stylidium flowers have highly integrated pistil and stamen tissues and functions; extreme differentiation among corolla lobes (within flowers) in shape s and function; tight, species-specific floral and corolla-lobe orientation; and extremely rapid (10-15 millisecond), “explosive” deposition of pollen on, and retrieval from, pollinators. These phenotypic specializations result in precise and accurate pollination and significantly segregated pollen flow among sympatric species, but not ecological specialization on a single group of pollinators. Instead all species studied to date are pollinated by a wide variety of large and small bees and flies, and occasionally even scarab beetles and long-proboscid Mecoptera. This ecological generalization is successful because of the “adaptive behavior” of the column, which automatically changes its angle and curvature at pollinator contact though interaction of the column with the morphology of the pollinator. These “behavioral” differences result in placement of pollen in different places on different kinds of pollinators and its retrieval from the correct spot on each.

1 - University of Alaska, Institute of Arctic Biology, PO Box 957000, Fairbanks, AK, 99775, USA
2 - Department of Parks and Wildlife, Western Australian Herbarium, Locked Bag 104, Bentley Delivery Centre, Perth, WA, 6983, Australia
3 - -Royal Botanic Gardens, Kew, Jodrell Laboratory, Richmond, Surrey, TW9 3DS, UK
4 - Royal Botanic Gardens, Kew, Jodrell Laboratory, Richmond, Surrey, TW9 3DS, UK

Keywords:
Adaptive floral behavior
pollination
Specialization
Stylidium
Western Australia.

Presentation Type: Colloquium Presentations
Session: C4
Location: Hall C/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 3:45 PM
Number: C4009
Abstract ID:217
Candidate for Awards:None