Skip to main content
Dryad

A morphological trait involved in reproductive isolation between Drosophila sister species is sensitive to temperature

Peluffo, Alexandre1; Hamdani, Mehdi1; Vargas-Valderrama, Alejandra1; David, Jean2; Mallard, François3; Graner, François4; Courtier-Orgogozo, Virginie1

Published Nov 24, 2025 on Dryad. https://doi.org/10.5061/dryad.kprr4xh1f

Data files

Nov 24, 2025 version files 927.53 MB

Click names to download individual files

Abstract

Male genitalia are usually extremely divergent between closely related species, but relatively constant within one species. Here, we examine the effect of temperature on the shape of the ventral branches, a male genital structure involved in reproductive isolation, in the sister species Drosophila santomea and D. yakuba. We designed a semi-automatic measurement machine learning pipeline that can reliably identify curvatures and landmarks based on manually digitized contours of the ventral branches. With this method, we observed that temperature does not affect ventral branches in D. yakuba, but that in D. santomea ventral branches tend to morph into a D. yakuba-like shape at lower temperatures. We found that male genitalia structures involved in reproductive isolation can be relatively variable within one species and can resemble the shape of closely related species’ genitalia through plasticity to temperature. Our results suggest that reproductive isolation mechanisms may be dependent on the environmental context.