Exciting article! In a recent Nature study, researchers sequenced the mitochondrial genome of a hominin linked to the Sima de Los Huesos ("Pit of Bones" in Northern Spain). They found that this hominin lived approximately 400,000 years ago, and also shared a common ancestor with Denisovans. These results were unexpected, as the fossilized remains from the Sima de Los Huesos shared morphological characteristics with the Neanderthals. The researchers propose that another hominin group may have carried Denisovan-like mtDNA (via gene flow) to the Sima de Los Huesos hominins. Taking these results into account, the researchers emphasize that this study opens the door to further work with hominins from the Middle Pleistocene.