Flower discrimination by pollinators in a dynamic chemical environment

Abstract

How hawkmoths sniff out a flower Pollinators such as butterflies and bees are the true targets of the flower odors we love so much. Though we might imagine insects “following their noses,” the wealth of odors in the real world can drown out the smell of a flower, making it hard to find. Riffel et al. found that hawkmoths find angel's trumpets by creating a neuronal picture within their antennal lobe, the part of the moth brain that receives olfactory signals from the antennae (see the Perspective by Szyszka). The picture represents both the flower and the background odors. Finding a flower involves a complex reading of both background and target odors, and changes in the background odors—including human pollutants—can hinder the process. Science , this issue p. 1515 ; see also p. 1454