Deceptive Behavior in Plants. II. Food Deception by Plants: From Generalized Systems to Specialized Floral Mimicry

Abstract

Most of the ca. 8,000 angiosperm species that lack floral rewards are orchids pollinated by food-seeking animals. The fitness benefits of floral deception are still being debated, but most of the available evidence suggests that food deception evolves because it strongly promotes cross-pollination. These plants are generally considered to employ either generalized food deception (exploiting innate preferences of pollinators) or Batesian floral mimicry (exploiting conditioned preferences of pollinators). However, we argue that there are also intermediate conditions between these two modes and that exploitation of conditioned preferences is probably more common among food-deceptive orchids than was previously realized. We also review evidence for ecological facilitation of the pollination of deceptive species by rewarding species via the “magnet effect.” We then consider the relative importance of visual and olfactory cues in food-deceptive systems. The role of scent in food-deceptive systems, especially generalized ones, is still poorly understood, but the available evidence indicates that floral color matching is a critical component of Batesian floral mimicry.