Studies show that genetics matter in who becomes a leader. However, we know little about the dynamic properties of the heritability of leadership emergence or how genetics might interact with environmental conditions to shape leadership emergence. We track leadership role occupancy at three time points among a cohort of 1,079 Danish twin pairs over ten years. Our results suggest that genetics matter less when the cohort is young and increase over time as the cohort grows older. We argue that labor market entry costs coupled with free access to education constrain the effect of genetics in the cohort during early adulthood, suggesting differing effects of the environment on genetic expression as the cohort ages. Sorting based on individual predisposition towards leadership likely strengthens as the cohort grows older and gains labor market experience. This result implies that we should not view the effect of genes on leadership role occupancy as static and that environmental experiences could disproportionately affect critical early leadership advancement. Our study reinforces calls to consider dynamic properties such as gene x environment interactions to advance our broader understanding of leadership’s biology.