Facial Morphogenesis of the Earliest Europeans

<div><p>The modern human face differs from that of our early ancestors in that the facial profile is relatively retracted (orthognathic). This change in facial profile is associated with a characteristic spatial distribution of bone deposition and resorption: growth remodeling. For humans, surface resorption commonly dominates on anteriorly-facing areas of the subnasal region of the maxilla and mandible during development. We mapped the distribution of facial growth remodeling activities on the 900–800 ky maxilla ATD6-69 assigned to <i>H. antecessor</i>, and on the 1.5 My cranium KNM-WT 15000, part of an associated skeleton assigned to African <i>H. erectus</i>. We show that, as in <i>H. sapiens</i>, <i>H. antecessor</i> shows bone resorption over most of the subnasal region. This pattern contrasts with that seen in KNM-WT 15000 where evidence of bone deposition, not resorption, was identified. KNM-WT 15000 is similar to <i>Australopithecus</i> and the extant African apes in this localized area of bone deposition. These new data point to diversity of patterns of facial growth in fossil <i>Homo</i>. The similarities in facial growth in <i>H. antecessor</i> and <i>H. sapiens</i> suggest that one key developmental change responsible for the characteristic facial morphology of modern humans can be traced back at least to <i>H. antecessor</i>.</p>