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bioRxiv · 10.1101/2020.03.22.002121

Neural processing genes are linked to divergence in visual mate preference in sympatric Heliconius butterflies

Abstract

Many animal species remain separate not because they fail to produce viable hybrids, but because their individuals choose not to mate. However, we still know very little of the genetic mechanisms underlying changes in these mate preference behaviours. Heliconius butterflies display bright warning patterns, which they also use to recognize conspecifics. Here, we couple QTL for divergence in visual preference behaviours with population genomic and gene expression analyses of neural tissue (central brain, optic lobes and ommatidia) across development in two sympatric Heliconius species. Within a region containing 200 genes, we identify five genes that are strongly associated with divergent visual preferences. Three of these have previously been implicated in key components of neural signalling (specifically an ionotropic glutamate receptor and two regucalcins), and overall our candidates suggest shifts in behaviour involve changes in visual integration or processing. This would allow preference evolution without altering perception of the wider environment.

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BibTeXRIS

Rossi, M., Thurman, T. J., Hausmann, A. E., Montgomery, S. H., Papa, R., Jiggins, C. D., Mcmillan, W. O., Merrill, R. M.. 2020-03-24. Neural processing genes are linked to divergence in visual mate preference in sympatric Heliconius butterflies. https://doi.org/10.1101/2020.03.22.002121

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