Meiosis, the process that produces sperm and eggs, is traditionally seen as very different in males and females. Female meiosis is asymmetric, creating one egg and three polar bodies, while male meiosis is thought to be symmetric, producing four sperm. However, some species challenge this view, showing that male meiosis can also be asymmetric, producing fewer sperm per germ cell. A new review from the lab explores how such asymmetry in males could influence inheritance patterns, potentially driving biased transmission of genes and challenging classical Mendelian rules.