Abstract
In some species, females choose mates possessing ornaments that predict offspring survival1,2,3,4,5. However, sexual selection by female preference for male genetic quality6,7,8 remains controversial because conventional genetic mechanisms maintain insufficient variation in male quality to account for costly preference and ornament evolution9,10. Here we show that females prefer ornaments that indicate genetic quality generated by transmission conflict between the sex chromosomes. By comparing sex-ratio distributions in stalk-eyed fly (Cyrtodiopsis) progeny we found that female-biased sex ratios occur in species exhibiting eye-stalk sexual dimorphism11,12 and female preferences for long eye span13,14. Female-biased sex ratios result from meiotic drive15, the preferential transmission of a ‘selfish’ X-chromosome. Artificial selection for 22 generations on male eye-stalk length in sexually dimorphic C. dalmanni produced longer eye-stalks and male-biased progeny sex ratios in replicate lines. Because male-biased progeny sex ratios occur when a drive-resistant Y chromosome pairs with a driving X chromosome15, long eye span is genetically linked to meiotic drive suppression. Male eye span therefore signals genetic quality by influencing the reproductive value of offspring16.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
