Hawkmoths evaluate scenting flowers with the tip of their proboscis

  1. Alexander Haverkamp
  2. Felipe Yon
  3. Ian W Keesey
  4. Christine Mißbach
  5. Christopher Koenig
  6. Bill S Hansson
  7. Ian T Baldwin
  8. Markus Knaden
  9. Danny Kessler  Is a corresponding author
  1. Max-Planck Institute for Chemical Ecology, Germany
  2. Max Planck Institute for Chemical Ecology, Germany

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

  1. Alexander Haverkamp

    Department of Evolutionary Neuroethology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  2. Felipe Yon

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  3. Ian W Keesey

    Department of Evolutionary Neuroethology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  4. Christine Mißbach

    Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  5. Christopher Koenig

    Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  6. Bill S Hansson

    Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    Bill S Hansson, Vice President of the Max Planck Society, one of the three founding funders of eLife, and a member of eLife's Board of Directors..
  7. Ian T Baldwin

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    Ian T Baldwin, Senior editor, eLife.
  8. Markus Knaden

    Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Jena, Germany
    Competing interests
    No competing interests declared.
  9. Danny Kessler

    Department of Molecular Ecology, Max-Planck Institute for Chemical Ecology, Jena, Germany
    For correspondence
    dkessler@ice.mpg.de
    Competing interests
    No competing interests declared.

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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  1. Alexander Haverkamp
  2. Felipe Yon
  3. Ian W Keesey
  4. Christine Mißbach
  5. Christopher Koenig
  6. Bill S Hansson
  7. Ian T Baldwin
  8. Markus Knaden
  9. Danny Kessler
(2016)
Hawkmoths evaluate scenting flowers with the tip of their proboscis
eLife 5:e15039.
https://doi.org/10.7554/eLife.15039

Share this article

https://doi.org/10.7554/eLife.15039

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