A non-coding indel polymorphism antagonistically affects fitness in Drosophila

This pattern is an example of 'antagonistic pleiotropy', where each gene variant has opposing effects on different aspects of an organism's performance, and likely contributes to maintaining genetic variation at this locus across worldwide populations of Drosophila. This is one of the first instances where sequence level variation can be demonstrated to have antagonistic fitness effects at different life stages and linked to genetic variation in the wild.

https://royalsocietypublishing.org/doi/10.1098/rspb.2020.2958