Hawkmoths evaluate scenting flowers with the tip of their proboscis
Abstract
Pollination by insects is essential to many ecosystems. Previously, we have shown that floral scent is important to mediate pollen transfer between plants (Kessler et al., 2015). Yet, the mechanisms by which pollinators evaluate volatiles of single flowers remained unclear. Here, Nicotiana attenuata plants, in which floral volatiles have been genetically silenced and its hawkmoth pollinator, Manduca sexta, were used in semi-natural tent and wind-tunnel assays to explore the function of floral scent. We found that floral scent not only functions to increase the fitness of individual flowers by increasing detectability but also by enhancing the pollinator's foraging efforts. Combining proboscis choice tests with neurophysiological, anatomical and molecular analyses we show that this effect is governed by newly discovered olfactory neurons on the tip of the moth's proboscis. With the tip of their tongue, pollinators assess the advertisement of individual flowers, an ability essential for maintaining this important ecosystem service.
Article and author information
Author details
Reviewing Editor
- Marcel Dicke, Wageningen University, Netherlands
Version history
- Received: February 9, 2016
- Accepted: May 3, 2016
- Accepted Manuscript published: May 5, 2016 (version 1)
- Version of Record published: May 26, 2016 (version 2)
Copyright
© 2016, Haverkamp et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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