Red Queen

Fine-scale association between parasites and sex in Potamopyrgus antipodarum within a New Zealand lake

Why sexual reproduction is so common despite major costs remains a widely debated evolutionary question. One of the most plausible potential explanations is the Red Queen hypothesis, which proposes that coevolving parasites can generate a selective advantage for sex. This hypothesis predicts that sexual reproduction should be most common where individuals experience a relatively high risk of parasitic infection.