Climate change alters marine species ranges but historical changes in habitability across global biomes and biota have not been evaluated. Here we reconstruct shifting distributions of aerobic habitat across global species physiological traits using gridded reconstructions of O₂ and temperature since 1960. Pervasive loss of O₂ drove an expansion of oxygen minimum zone (OMZ) volume across all ocean basins and for all O₂ thresholds of hypoxia tolerance. However, variable thermal sensitivity of hypoxia tolerance among species creates a richer tapestry of habitat changes including both expansions and contractions. Gains and losses of aerobic habitat are strongly structured by latitude, with modest net gains concentrated at low latitudes and pronounced losses dominating toward higher latitudes in both hemispheres. Earth System Models underestimated the magnitude of historical aerobic habitat change, indicating that climate-driven habitat reorganization has already been stronger and more heterogeneous than previously thought.