Ruffs are characterized by three supergene variants that lead to different appearances and courtship behavior in males. Whether these variants affect females was previously unknown. Researchers at the Max Planck Institute for Biological Intelligence, in foundation (i.f.), now show that females of the so-called Faeder variant produce less offspring. However, this female handicap helps their males: Disguised as females, Faeder males benefit from their own rarity and obtain more matings. The contrasting effect of the variant in males and females thus contributes to its persistence over time. The study thereby provides important insights into the mechanisms that maintain biodiversity.