Mimicry and Deception in Pollination

Abstract

Mimicry and deception in pollination represent extended plant–pollinator communication systems including two senders of mistakable signals. Flower mimicry is a highly diverse phenomenon including Batesian mimicry, in which a nonrewarding flower mimics a rewarding one, and signal standardization, also known as Mullerian mimicry, in which two unrelated rewarding flowers display similar signals. In these floral mimicry systems, even experienced flower visitors are deceived. Some flowering plants exploit the pollinators' innate preferences of finding rewarding flowers or floral rewards: In some cases the flowers fit the innate search image of flower visitors so close that no real model exists. In other cases, only the floral reward is mimicked. Particularly, pollen and stamen mimicry systems are very common, in which flowers mimic visual and tactile signals of pollen and stamens, and by means of this fake stamens and pollen deceive or misdirect pollen-eating and pollen-collecting flower visitors that innately respond to these signals. In another type of floral mimicry, animal-pollinated flowers attract flower visitors by mimicking features related to aspects other than flower visitation of their pollinators, e.g., sexually deceptive flowers deceiving mate-seeking male insects, and brood-substrate mimicking flowers deceiving females searching for egg-laying substrates. These deceptive flowers attract specific pollinators by means of sensory exploitation of a well-developed innate behavioural response for distinct volatiles and other cues that have evolved in the context of mating or egg-laying behaviour. Floral mimicry is always beneficial for the mimic, but may impose costs for the deceived pollinators. Then the deceived pollinators likely evolve mechanisms not being deceived and the flowering plants to continue deception, and deception becomes trickier over evolutionary times.