Divergent sensory investment mirrors potential speciation via niche partitioning across Drosophila
Abstract
The examination of phylogenetic and phenotypic characteristics of the nervous system, such as behavior and neuroanatomy, can be utilized as a means to assess speciation. Recent studies have proposed a fundamental tradeoff between two sensory organs, the eye and the antenna. However, the identification of ecological mechanisms for this observed tradeoff have not been firmly established. Our current study examines several monophyletic species within the obscura group, and asserts that despite their close relatedness and overlapping ecology, they deviate strongly in both visual and olfactory investment. We contend that both courtship and microhabitat preferences support the observed inverse variation in these sensory traits. Here, this variation in visual and olfactory investment seems to provide relaxed competition, a process by which similar species can use a shared environment differently and in ways that help them coexist. Moreover, that behavioral separation according to light gradients occurs first, and subsequently, courtship deviations arise.
Data availability
All data supporting the findings of this study, including methodology, display examples, raw confocal images and z-stack scans, statistical assessments, courtship videos, as well as other supplementary materials are all available with the online version of this publication. An additional, online data depository also contains raw data from this publication, and this material can be accessed via EDMOND, the Open Access Data Repository of the Max Planck Society (MPG):https://dx.doi.org/10.17617/3.3v
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Divergent sensory investment mirrors potential speciation via niche partitioning across DrosophilaEDMOND, the open access data repository of the Max Planck Society.
Article and author information
Author details
Funding
Max-Planck-Gesellschaft (Open-access funding)
- Ian W Keesey
- Veit Grabe
- Markus Knaden
- Bill S Hansson
The funding organization had no role in the study design, data collection, interpretation, nor the decision to submit the work for publication. The authors declare no competing interests.
Copyright
© 2020, Keesey 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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