Evolutionary Ecology

, Volume 29, Issue 3, pp 311–322

Are flowers red in teeth and claw? Exploitation barriers and the antagonist nature of mutualisms

Original Paper


The romantic perception of plant–animal mutualisms as a cooperative endeavour has been shattered in the last decades. While the classic theory of plant–pollinator coevolution assumed that partner coevolution is largely mutualistic, an increasing appreciation of the inherent conflict of interests between such partners has led to the realization that genes that confer a reproductive advantage to plants may have negative effects on their pollinators (and vice versa), giving rise to an apparent paradox: that antagonistic processes may drive coevolution among mutualistic partners. Under this new paradigm, mutualistic partners are bound by mutual interest but shaped by “selfish” antagonistic processes. Exploitation barriers mediated by resource competition among pollinators are a key element of this paradigm. Exploitation barriers involve traits such as tubular corollas, red flowers, toxic or deterrent rewards, and attractants of floral predators. Exploitation barriers result in resource partitioning, increasing floral fidelity of favoured pollinators and therefore plant fitness; but they often entail a physiological, behavioural or developmental cost for such favoured pollinators. Resource partitioning mediated by exploitation barriers is a very powerful driver of floral diversification, robust to variation in pollinator assemblages; hence, it may contribute to elucidating the occurrence of co-evolutionary changes in multi-species contexts. Exploitation barriers provide also a mechanistic basis for trait-based modelling of interaction networks, and represent a reason for caution in assuming fixed interaction identity or strength when modelling such networks (e.g. in rarefaction procedures used to estimate secondary extinctions). We propose to replace the misleading metaphor that depicts flowers and pollinators as cooperative partners by a metaphor in which plants and pollinator are traders, seeking to obtain different services from each other in complete disregard for the benefit of their mutualistic partner.


Exploitation barriers Plant–pollinator interaction Optimal foraging Resource partitioning Competition Mutualism Antagonism 


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Estación Biológica de Doñana, EBD-CSICIsla de la CartujaSpain
  2. 2.Estación Experimental de Zonas Áridas, EEZA-CSICLa Cañada de San UrbanoSpain

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