More than colour attraction: behavioural functions of flower patterns

Highlights

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  Insects perceive separately chromatic and achromatic aspects of colour patterns.

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  Flowers present colour patterns as individual or shared displays.

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  Visual appearance of flowers changes considerably with viewing distance.

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  Pollinators use close-up views for landing and handling of flowers.

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  Further away shared displays within the visual scene guide approach trajectories.

Abstract

Flower patterns are thought to influence foraging decisions of insect pollinators. However, the resolution of insect compound eyes is poor. Insects perceive flower patterns only from short distances when they initiate landings or search for reward on the flower. From further away flower displays jointly form larger-sized patterns within the visual scene that will guide the insect's flight. Chromatic and achromatic cues in such patterns may help insects to find, approach and learn rewarded locations in a flower patch, bringing them close enough to individual flowers. Flight trajectories and the spatial resolution of chromatic and achromatic vision in insects determine the effectiveness of floral displays, and both need to be considered in studies of plant–pollinator communication.