Ontogeny of the maxilla in Neanderthals and their ancestors

Abstract

Neanderthals had large and projecting (prognathic) faces similar to those of their putative ancestors from Sima de los Huesos (SH) and different from the retracted modern human face. When such differences arose during development and the morphogenetic modifications involved are unknown. We show that maxillary growth remodelling (bone formation and resorption) of the Devil's Tower (Gibraltar 2) and La Quina 18 Neanderthals and four SH hominins, all sub-adults, show extensive bone deposition, whereas in modern humans extensive osteoclastic bone resorption is found in the same regions. This morphogenetic difference is evident by ∼5 years of age. Modern human faces are distinct from those of the Neanderthal and SH fossils in part because their postnatal growth processes differ markedly. The growth remodelling identified in these fossil hominins is shared with Australopithecus and early Homo but not with modern humans suggesting that the modern human face is developmentally derived.

Fetal and neonatal maxillary ontogeny in extant humans and the utility of prenatal maxillary morphology in predicting ancestral affiliation

“…This holds true across H. sapiens and genus Homo more broadly, due to climate-related variation in nasal morphology coupled with dentofacial variation such as facial prognathism. Recent work indicates that this midfacial variation arises through differential deposition and resorption of bone across taxa, which can be seen in early childhood (Lacruz et al, 2015). An interesting avenue for future research might compare bone depositional patterns at the fetal/neonatal period of development, examining whether differences in subnasal alveolar prognathism in modern humans arise from differential depositional patterns.…”

Aspects of human physical and behavioural evolution during the last 1 million years

“…There are also further data on the early evolution of the lineages of H. neanderthalensis and H. sapiens. The large fossil sample from the Sima de los Huesos in Atapuerca can now be firmly placed in the Neanderthal clade through cranial and dental morphology, facial growth patterns, and genomic DNA, and has been dated from associated sediments to~430 ka (Arsuaga et al, 2014;Lacruz, 2015;Meyer et al, 2016). A possible equivalent on the sapiens lineage, although younger in age, has now been established from the Jebel Irhoud site in Morocco.…”

Shape analysis of spatial relationships between orbito‐ocular and endocranial structures in modern humans and fossil hominids

“…Compared with Neanderthals and Middle Pleistocene humans, modern humans have smaller, narrower and vertically shorter faces that are flatter and more retracted (Bastir & Rosas, 2016). It remains to be established whether modern human facial morphology is derived, or rather, is a primitive condition (Arsuaga et al 1999;Berm udez de Castro et al 2010;Freidline et al 2013;Lacruz et al 2015;Stringer, 2016). Nonetheless, this unique morphological configuration, characterized by reduced facial block and expanded braincase, is highly specific to our species.…”

“…; Lacruz et al. ; Stringer, ). Nonetheless, this unique morphological configuration, characterized by reduced facial block and expanded braincase, is highly specific to our species.…”