Intrinsic molecular programs and extrinsic factors including pro-inflammatory molecules are understood to regulate hematopoietic aging. This is based on foundational studies using genetic perturbation to evaluate causality. However, individual organisms exhibit natural variation in hematopoietic aging phenotypes and the molecular basis of this heterogeneity is poorly understood. Here, we generated individual single cell transcriptomic profiles of hematopoietic and non-hematopoietic cell types …