Business as usual will commit biodiversity to genetic erosion: parallels from climate change for proactive conservation

Biodiversity and climate resilience are tightly linked. Genetic diversity enables species to adapt in a rapidly changing world, yet its loss (genetic erosion) remains the least visible dimension of the biodiversity crisis. Although climate science has long recognised that past emissions can lock in future climate impacts (“committed climate change”), the idea that biodiversity also faces future, lagged losses is less embedded in policy and public discourse. Past and ongoing habitat loss, fragmentation, and population declines have, however, already committed many species to future genetic erosion, with losses that may be undetectable today being capable of precipitating species extinctions and ecosystem collapse. To highlight the urgency of this issue, we conceptualise “committed genetic erosion” using four climate science parallels. First, just as the climate system is showing clear signals of change, genetic erosion is already occurring across regions and taxa, including non-threatened species. Second, like inertia in the climate system, biological inertia creates time lags between demographic decline and genetic erosion, effectively locking in further loss under business as usual. Third, just as climate science relies on indicators and forecasting tools, genetic indicators and forward-looking simulations can identify risk, quantify committed genetic erosion, and project future trajectories under alternative management pathways. Fourth, both the climate and biodiversity crises require ambitious action that addresses root causes. Proactively maintaining large, connected populations, and enabling carefully designed genetic rescue, provide proven, effective interventions for maintaining species’ resilience, unlike reactive strategies or speculative technological fixes. Because genetic inertia operates locally, the lag period offers a critical window for intervention. This is a strategic advantage we cannot afford to miss: acting early and placing genetic diversity at the centre of biodiversity management can safeguard the adaptive potential of life on Earth.