Fossil remains found at Atapuerca, Spain, indicate Homo antecessor had an increased brain size (approximately 1,000 cc), a flattened face, a deep fossa between the nasal aperture and the zygomatic (cheek bone), and large canines and incisors. Some anthropologists suggest H. antecessor may be the last common ancestor of modern humans and Neanderthals (via Homo heidelbergensis) because H. antecessor has a combination of primitive traits typical of earlier Homo and unique features seen in neither Neanderthals or Homo sapiens. The type specimen for H. antecessor is ATD 6-5 which was found at Atapuerca and dates to approximately 780,000 years ago.