Mating increases Drosophila melanogaster females’ choosiness by reducing olfactory sensitivity to a male pheromone

• Published in: Nature ecology & evolution Vol. 5; no. 8; pp. 1165 - 1173
• Main Authors: Kohlmeier, Philip, Zhang, Ye, Gorter, Jenke A., Su, Chih-Ying, Billeter, Jean-Christophe
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.08.2021; Nature Publishing Group
• Subjects: 13/89; 38/91; 631/181/2470; 631/378/3919; 64/24; Animals; Biological and Physical Anthropology; Biomedical and Life Sciences; Desensitization; Drosophila melanogaster; Ecology; Evolutionary Biology; Female; Females; Fruit flies; Insects; Juvenile hormones; Life Sciences; Male; Males; Neuromodulation; Neurons; Offspring; Olfactory neurons; Olfactory thresholds; Paleontology; Pheromones; Plasticity; Polyandry; Reproduction; Selectivity; Sexual Behavior, Animal; Sperm; Spermatozoa; Zoology
• ISSN: 2397-334X; 2397-334X
• DOI: 10.1038/s41559-021-01482-4

Females that are highly selective when choosing a mate run the risk of remaining unmated or delaying commencing reproduction. Therefore, low female choosiness would be beneficial when males are rare but it would be maladaptive if males become more frequent. How can females resolve this issue? Polyandry would allow mating-status-dependent choosiness, with virgin females selecting their first mate with little selectivity and becoming choosier thereafter. This plasticity in choosiness would ensure timely acquisition of sperm and enable females to increase offspring quality during later mating. Here, we show that Drosophila melanogaster females display such mating-status-dependent choosiness by becoming more selective once mated and identify the underlying neurohormonal mechanism. Mating releases juvenile hormone, which desensitizes Or47b olfactory neurons to a pheromone produced by males, resulting in increased preference for pheromone-rich males. Besides providing a mechanism to a long-standing evolutionary prediction, these data suggest that intersexual selection in D. melanogaster , and possibly in all polyandrous, sperm-storing species, is mainly the domain of mated females since virgin females are less selective. Juvenile hormone influences behaviour by changing cue responsiveness across insects; the neurohormonal modulation of olfactory neurons uncovered in D. melanogaster provides an explicit mechanism for how this hormone modulates behavioural plasticity. This study shows that Drosophila melanogaster females are more selective after their first mating because mating triggers the increased release of juvenile hormone, which desensitizes the Or47b olfactory neurons to an aphrodisiac pheromone produced by males.