Ancient life has been resurrected from the bowels of a military tunnel that penetrates the Alaskan permafrost. Some of the microbes thawed from these long-frozen soils have been trapped for 40,000 years. Now, they've been reawakened. "These are not dead samples by any means," says microbiologist and geochemist Tristan Caro, a PhD student at the University of Colorado Boulder (CU Boulder) during the study. "They're still very much capable of hosting robust life that can break down organic matter