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Cited by 108Pleistocene-Era Hominins and ArchaeologyMorphological variations and asymmetryEvolutionary Psychology and Human Behavior

The evolutionary history of the human face

Open access
Lacruz, Rodrigo S., Stringer, Chris B., Kimbel, William H., Wood, Bernard, Harvati, Katerina, O’Higgins, Paul, Bromage, Timothy G., Arsuaga, Juan-Luis·2019·Nature Ecology & Evolution
DOI 10.1038/s41559-019-0865-7
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Abstract

The face is the most distinctive feature used to identify others. Modern humans have a short, retracted face beneath a large globular braincase that is distinctively different from that of our closest living relatives. The face is a skeletal complex formed by 14 individual bones that houses parts of the digestive, respiratory, visual and olfactory systems. A key to understanding the origin and evolution of the human face is analysis of the faces of extinct taxa in the hominin clade over the last 6 million years. Yet, as new fossils are recovered and the number of hominin species grows, the question of how and when the modern human face originated remains unclear. By examining key features of the facial skeleton, here we evaluate the evolutionary history of the modern human face in the context of its development, morphology and function, and suggest that its appearance is the result of a combination of biomechanical, physiological and social influences.

AI snapshot

Written from the paper’s full text.

TL;DR

The human face is a 14-bone skeletal complex whose modern short, retracted form evolved over the last ~4 million years through a mix of biomechanical, physiological, and social influences. The paper reviews fossil, developmental, genetic, and morphometric evidence and argues that a modern human-like face appears by ~300 Ka at Jebel Irhoud, with H. antecessor (~850 Ka) as a key possible ancestral morphology.

Key findings

  • The modern human face is relatively small and nonprojecting, lacks pronounced supraorbital and midfacial prognathism, and has a canine fossa; these features do not appear all at once, but crucial elements are present in the earliest H. sapiens lineage, including Jebel Irhoud at ~300 Ka.
  • H. antecessor specimen ATD6-69 (~850 Ka) shows a “modern” maxillary conformation, and growth simulations and remodeling analyses support its modern-like facial development; Sima de los Huesos fossils (~430 Ka) share facial features with Neanderthals and are regarded as Neanderthal ancestors.
  • Facial evolution in hominins involved modular changes: early Ardipithecus and Australopithecus differ in masticatory structures, with Au. afarensis (~3.7–3.0 Ma) showing expansive zygomatic bones and robust masticatory anatomy, while Ar. ramidus (~4.4 Ma) has lightly built zygomatic bones and arches.
  • Modern human facial variation reflects both population history and environmental factors; facial morphology carries a neutral genetic signal but is more strongly affected by climate than other cranial regions, especially in high-latitude populations, and nasal morphology is related to temperature and humidity.

Methods

  • Review/synthesis of the hominin facial skeleton over the last ~4 Ma, focusing on australopiths, early Homo, Middle Pleistocene hominins, and H. sapiens, with key specimens listed in Table 1.
  • Evidence includes comparative craniofacial morphology, developmental growth-remodeling maps of bone deposition and resorption, ancient DNA and quantitative genetic studies, and a principal components analysis of 19 facial three-dimensional landmarks in Pleistocene fossils and modern humans.
  • This is a review; the analyses are drawn from cited studies and previously analyzed morphometric data rather than newly collected primary data.

Limitations

  • The paper states that a detailed account of human facial evolution is difficult because of the intricate nature of facial development and the many pre- and post-natal factors influencing the face.
  • The paper states that future work must integrate potentially conflicting evidence from craniofacial biomechanics, occlusal microwear, and stable isotopes, and must disentangle shared ancestry, climate adaptation, and subsistence effects.
  • Evident from the text: the fossil record is fragmentary and uneven; H. naledi is too incomplete in the face to add much, the Harbin cranium is announced but “not yet published scientifically,” and the identity of the last common ancestor remains unresolved.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s41559-019-0865-7

Cites

102 of 102 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 87 cited sources checked · 0 supported · 0 flagged

  • Findingreasoning

    Over time, the human face became more gracile.

    “Over time, the face became more gracile”
    Quote in the paperSubstantial claim
  • Findingnone given

    Asian specimens such as Nanjing also evidence that the face evolved more rapidly than other cranial components in Middle Pleistocene hominins.

    “This is also evidenced in Asian specimens such as Nanjing.”
    Quote in the paperNot a substantial claim
  • Findingnone given

    Some sexually dimorphic structures such as canines and browridges reduced in size over time during the australopith to early Homo transition.

    “since some sexually dimorphic structures (e.g.canines, browridges) reduced in size over time.”
    Quote in the paperNot a substantial claim
  • Findingreasoning

    In Middle Pleistocene hominins, the face evolved more rapidly than other cranial components.

    “A striking feature observed in the MP hominins is that the face evolved more rapidly than other cranial components”
    Quote in the paperSubstantial claim
  • Findingown data

    Morphometric analysis of the face discriminates Pleistocene fossils.

    “Figure 5: Morphometric analysis of the face discriminates Pleistocene fossils.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. 27
  • May combine two claims. 36

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Findingnone given

    In more recent fossil Homo, facial projection decreased further, with a moderate but cumulative increase in brain size.

    “In more recent fossil Homo, facial projection decreased further, with a moderate but cumulative increase in brain size.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingnone given

    Homo antecessor presents modern facial features while retaining some primitive characters elsewhere in the cranium.

    “as illustrated by the facial characteristics of H. antecessor, a key LCA candidate, presenting modern facial features while retaining some primitive characters elsewhere in the cranium.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Irhoud 1 already shows almost completely modern human-like facial morphology, unlike Neanderthals and other Middle Pleistocene crania.

    “unlike Neanderthals and other MP crania (Petralona, Bodo, Broken Hill 1, Sima de los Huesos), Irhoud 1 already shows almost completely modern human-like facial morphology.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Modern humans are distinguished by a flat and anteriorly oriented face, angled zygomatic, and gracile browridge, contrasting with the large browridge and puffy midface of Neanderthals.

    “Modern humans are distinguished by a flat and anteriorly oriented face, angled zygomatic, and gracile browridge (top left), contrasting with the large browridge and 'puffy' midface of the Neanderthals (bottom left).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    In prognathic faces such as chimpanzees or early Australopithecus, prognathism is characterized by a pattern of bone deposition.

    “In prognathic faces such as in chimpanzees or early Australopithecus, this prognathism is characterized by a pattern of bone deposition.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Growth remodeling can be determined by analysis of the distribution of depository and resorptive fields on bone surfaces due to the activities of osteoblasts and osteoclasts.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Cranial neural crest cells are the main contributors to the development of the facial skeleton.

    “the main contributors to the development of the facial skeleton 2”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [2] Cordero, D. R. et al. Cranial neural crest cells on the move: their roles in craniofacial development. Am. J. Med. Genet. A. 155A, 270–279 (2011). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Facial shape appears to be influenced by a limited set of candidate genes.

    “Facial shape appears to be influenced by a limited set of candidate genes 3”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [3] Liu, F. et al. A genome-wide association study identifies five loci influencing facial morphology in Europeans. PLoS Genet. 8, e1002932 (2012). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The face signals more than 20 different categories of emotion via contraction or relaxation of muscles.

    “signaling more than 20 different categories of emotion via the contraction or relaxation of muscles 1”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1] Du, S., Tao, Y. & Martinez, A. M. Compound facial expressions of emotion. Proc. Natl Acad. Sci. USA 111, E1454–E1462 (2014). source

      Not checked in the free run.

  • May combine two claims.

    Premisenone given

    The modern human face is distinct from that of earlier hominin species in being relatively small and nonprojecting, showing a canine fossa below the orbit, and lacking the pronounced supraorbital structures and alveolar and midfacial prognathism exhibited by Middle Pleistocene hominins.

    “The modern human face is distinct from that of earlier hominin species in several important ways (Fig. 3h): it is relatively small and nonprojecting, shows a depression -the 'canine fossa' -below the orbit and lacks the pronounced supraorbital structures and the alveolar and midfacial prognathism exhibited by MP hominins.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    A shift towards a strong C4 dietary signature occurred in Homo with the appearance of early African H. erectus at or before 1.7 Ma, rather than in the earlier species H. habilis and H. rudolfensis, whose modal carbon stable isotope signal is similar to that of Au. afarensis and Au. africanus, suggesting a mixed C3/C4 diet.

    “a shift towards a strong C4 dietary signature occurred in Homo with the appearance of early African H. erectus (≤ 1.7 Ma), rather than in the earlier species H. habilis and H. rudolfensis, whose modal carbon stable isotope signal is similar to that of Au. afarensis and Au.africanus, suggesting a mixed C3/C4 diet 19”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [19] Cerling, T. E. et al. Stable isotope-based diet reconstructions of Turkana Basin hominins. Proc. Natl Acad. Sci. USA 110, 10501–10506 (2013). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The earliest known stone tools, at 3.3 Ma, coincide in time with Au. afarensis and K. platyops and predate the earliest fossils of Homo by several hundred thousand years.

    “the earliest known stone tools, at 3.3 Ma 26 , coincide in time with Au. afarensis (and the australopith-grade taxon K. platyops of eastern Africa), predating the earliest fossils of Homo by several hundred thousand years”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [26] Harmand, S. et al. 3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya. Nature 521, 310–315 (2015). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Au. sediba shares derived facial features with Au. africanus, but its facial remodeling differs from all other Australopithecus facial skeletons.

    “The younger species Au. sediba (~2.0 Ma) from South Africa 23 shares derived facial features with Au. africanus 10 , but its facial remodeling differs from all other Australopithecus facial skeletons (see Box 2, Fig. 2) 15”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [10] Kimbel, W. H. & Rak, Y. Australopithecus sediba and the emergence of Homo: questionable evidence from the cranium of the juvenile holotype MH 1. J. Hum. Evol. 107, 94–106 (2017). source

      Not checked in the free run.

    • cites [15] Lacruz, R. S. et al. Distinct growth of the nasomaxillary complex in Au. sediba. Sci. Rep. 5, 15175 (2015). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

    Premisecitation

    Using recently published estimates of the autosomal human mutation rate, the divergence date of the H. neanderthalensis and H. sapiens lineages could be placed between 550 and 765 Ka.

    “using recently published estimates of the autosomal human mutation rate, it has been suggested that the divergence date of the H. neanderthalensis and H. sapiens lineages could indeed be placed earlier -between 550 and 765 Ka 48”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [48] Meyer, M. et al. Nuclear DNA sequences from the Middle Pleistocene Sima de los Huesos hominins. Nature 531, 504–507 (2016). source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Stringer argued that shape resemblances between the Petralona and Broken Hill 1 crania indicated the existence of a widespread Middle Pleistocene population which, if the Mauer mandible is included, would be called H. heidelbergensis.

    “Stringer 32 has argued that shape resemblances between the Petralona and Broken Hill 1 crania indicated the existence of a widespread MP population which, if the Mauer mandible (Germany) is included, would be called H. heidelbergensis.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [32] Stringer, C. B. Some further notes on the morphology and dating of the Petralona hominid. J. Hum. Evol. 12, 731–742 (1983). source

      Not checked in the free run.

  • May combine two claims.

    Premiseown data

    The modern facial morphology present in two fossils from Irhoud is similar to that shown by Florisbad and Herto at a somewhat later date, Ndutu and Thomas Quarry at an earlier date, and the currently undated Eliye Springs and Broken Hill 2 fossils.

    “This morphology is similar to that shown by Florisbad (South Africa) and Herto (Ethiopia) (Fig. 3g) at a somewhat later date, Ndutu and Thomas Quarry at an earlier date, and in the currently undated Eliye Springs (Kenya) and Broken Hill 2 fossils.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    One implication of a H. heidelbergensis-like last common ancestor is that the zygomaxillary morphology found in large Middle Pleistocene crania would have undergone gracilisation to become the form found in recent H. sapiens, and a second trajectory featuring increased midfacial projection and maxillary inflation led to the facial configuration found in Neanderthals.

    “One implication of a H. heidelbergensis-like LCA would be that the zygomaxillary morphology found in these large MP crania would have undergone gracilisation to become the form found in recent H. sapiens, and a second trajectory, featuring increased midfacial projection and maxillary inflation, that led to the facial configuration found in the Neanderthals.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisenone given

    The face of early H. erectus is more modern human-like than that of either H. habilis or H. rudolfensis, with a more vertical profile featuring a retracted subnasal plate and a prominent nasal bridge.

    “the face of early H. erectus is more modern human-like than that of either H. habilis or H. rudolfensis, with a more vertical profile featuring a retracted subnasal plate and a prominent nasal bridge”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Sexual dimorphism could be a factor if Thomas Quarry, Ndutu and Broken Hill 2 represent female individuals, and Petralona, Broken Hill 1 and Bodo much larger males.

    “Thus, sexual dimorphism could also be a factor if Thomas Quarry, Ndutu and Broken Hill 2 represent female individuals, and Petralona, Broken Hill 1 and Bodo much larger males.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    Allometric factors may influence zygomaxillary morphology when comparing smaller and larger individuals, given the association between body size and facial size in primates.

    “It is possible that allometric factors influence the zygomaxillary morphology when comparing smaller and larger individuals 37,38 given the association between body size and facial size in primates 39”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [37] Maddux, S. D. & Franciscus, R. G. Allometric scaling of infraorbital surface topography in Homo. J. Hum. Evol. 56, 161–174 (2009). source

      Not checked in the free run.

    • cites [38] Freidline, S. E., Gunz, P., Harvati, K. & Hublin, J. J. Evaluating developmental shape changes in Homo antecessor subadult facial morphology. J. Hum. Evol. 65, 404–423 (2013). source

      Not checked in the free run.

    • cites [39] Dobson, S. D. Allometry of facial mobility in anthropoid primates: implications for the evolution of facial expression. Am. J. Phys. Anthropol. 138, 70–81 (2009). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The modern appearance of ATD6-69 is substantiated by growth simulations based on both Neanderthal and modern human facial growth trajectories, and by analysis of facial growth and remodeling that identified resorptive fields similar to those found in sub-adult H. sapiens.

    “The modern appearance of ATD6-69 is also substantiated by growth simulations of this specimen based on both the Neanderthal and modern human facial growth trajectories 38 , and by the analysis of the facial growth and remodeling of ATD6-69, which identified resorptive fields on that maxilla similar to those found in sub-adult H. sapiens 16”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [38] Freidline, S. E., Gunz, P., Harvati, K. & Hublin, J. J. Evaluating developmental shape changes in Homo antecessor subadult facial morphology. J. Hum. Evol. 65, 404–423 (2013). source

      Not checked in the free run.

    • cites [16] Lacruz, R. S. et al. Facial morphogenesis of the earliest europeans. PLoS One 8, e65199 (2013). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Middle Pleistocene hominins are a possible ancestral pool for the emergence of Homo sapiens, and Middle Pleistocene taxa could include the last common ancestor of H. sapiens and other now extinct taxa.

    “These MP hominins are a possible ancestral pool for the emergence of Homo sapiens.Hence, MP taxa could include the last common ancestor (LCA) of H. sapiens and other now extinct taxa.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The H. antecessor-like last common ancestor model implies that a H. antecessor-like facial morphology was retained in the descendant H. sapiens lineage but was modified in that of the Neanderthals.

    “This model implies that a H. antecessor-like facial morphology was retained in the descendant H. sapiens lineage, but was modified in that of the Neanderthals.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    It was argued that H. heidelbergensis represented the best candidate for the last common ancestor of the H. sapiens and H. neanderthalensis lineages.

    “it was argued that this species represented the best candidate for the LCA of the H. sapiens and H. neanderthalensis lineages (see also 35 )”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [32] Stringer, C. B. Some further notes on the morphology and dating of the Petralona hominid. J. Hum. Evol. 12, 731–742 (1983). source

      Not checked in the free run.

    • cites [35] Rightmire, G. P. Human evolution in the Middle Pleistocene: the role of Homo heidelbergensis. Evol. Anthropol. 6, 218–227 (1998). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Adaptive explanations for an enlarged midface and large brows have focused either on enlargement of the nasal cavity and paranasal sinuses emphasizing respiratory/energetic demands and climatic adaptation, or on mechanical adaptations to diet, paramasticatory activity, or increase in body size.

    “Adaptive explanations for an enlarged midface and large brows have focused either on enlargement of the nasal cavity and paranasal sinuses emphasizing respiratory/energetic demands 56 and climatic adaptation 57,58 , or on mechanical adaptations to diet, paramasticatory activity 59,60 , or increase in body size [61][62][63][64]”
    Quote in the paperNot a substantial claim0 of 5 sources checked
    • cites [56] García-Martínez, D. et al. Ribcage measurements indicate greater lung capacity in Neanderthals and Lower Pleistocene hominins compared to modern humans. Commun. Biol. 1, 117 (2018). source

      Not checked in the free run.

    • cites [57] Churchill, S.E. in Neanderthals Revisited: New Approaches and Perspectives (eds. Havarti, K. & Harrison, T.) 113–133 (Springer, 2006). source

      Not checked in the free run.

    • cites [58] Wroe, S. et al. Computer simulations show that Neanderthal facial morphology represents adaptation to cold and high energy demands, but not heavy biting. Proc. R. Soc. Lond. B 285, 20180085 (2018). source

      Not checked in the free run.

    • cites [59] Rak, Y. The Neanderthal: a new look at an old face. J. Hum. Evol. 15, 151–164 (1986). source

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    • cites [60] Demes, B. Another look at an old face: biomechanics of the Neandertal facial skeleton reconsidered. J. Hum. Evol. 16, 297–303 (1987). source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    An alternative is to consider a H. antecessor-like facial morphology as more likely for the last common ancestor of H. sapiens and H. heidelbergensis, with the H. heidelbergensis group exemplified by Petralona, Bodo and Broken Hill 1 having more in common facially with the Sima de los Huesos fossils and subsequent Neanderthals.

    “An alternative would be to consider a H. antecessorlike facial morphology as more likely for the LCA of H. sapiens and H. heidelbergensis, with the H. heidelbergensis group exemplified by Petralona, Bodo and Broken Hill 1 having more in common facially with the Sima de los Huesos fossils and subsequent Neanderthals.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The evidence suggests that the large and non-H. sapiens-like faces of Bodo and Broken Hill 1 represent taxonomic diversity in the African Middle Pleistocene record, which could exclude the large fossils assigned to H. heidelbergensis/H. rhodesiensis as representing an ancestral morph for H. sapiens.

    “The evidence instead suggests that the large and non-H.sapiens-like faces of Bodo and Broken Hill 1 (Figs.3b & c), represent taxonomic diversity in the African MP record, which could exclude the large fossils assigned to H. heidelbergensis/H.rhodesiensis as representing an ancestral morph for H. sapiens.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Initial changes in the early hominin face were focused in the central and upper portions of the face, perhaps in response to changes in the function of the canines and supraorbital region in social signaling, whereas subsequent changes mainly involved the masticatory apparatus.

    “The initial changes were focused in the central and upper portions of the face, perhaps in response to changes in the function of the canines and supraorbital region in social signaling, whereas subsequent changes mainly involved the masticatory apparatus.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The derived craniofacial features of Australopithecus species have long been interpreted as adaptations to mechanically tough or hard plant foods that dominated in African environments during late Pliocene aridification at or before 2.8-2.7 Ma.

    “These derived features have long been interpreted as adaptations to mechanically tough or hard plant foods that dominated in African environments during a period of aridification in the late Pliocene (≤ 2.8-2.7 Ma) 20,21”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [20] deMenocal, P. B. Plio-Pleistocene African climate. Science 270, 53–59 (1995). source

      Not checked in the free run.

    • cites [21] Trauth, M. H. et al. High- and low-latitude forcing of Plio-Pleistocene East African climate and human evolution. J. Hum. Evol. 53, 475–486 (2007). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    While fully fledged H. sapiens likely had an African beginning, the evolutionary origins of traits characteristic of the modern face, represented by the last common ancestor, may be found elsewhere.

    “while fully fledged H. sapiens likely had an African beginning, the evolutionary origins of traits characteristic of the modern face, represented by the LCA, may be found elsewhere”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Both external nasal morphology and the nasal cavity are related to temperature and humidity.

    “both the external nasal morphology and nasal cavity are related to temperature and humidity 80,82,85”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [80] von Cramon-Taubadel, N. Evolutionary insights into global patterns of human cranial diversity: population history, climatic and dietary effects. J. Anthropol. Sci. 92, 43–77 (2014).

      Not checked in the free run.

    • cites [82] Hubbe, M., Hanihara, T. & Harvati, K. Climate signatures in the morphological differentiation of worldwide modern human populations. Anat. Rec. (Hoboken) 292, 1720–1733 (2009). source

      Not checked in the free run.

    • cites [85] Noback, M. L., Harvati, K. & Spoor, F. Climate-related variation of the human nasal cavity. Am. J. Phys. Anthropol. 145, 599–614 (2011). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Midfacial reduction may have arisen simply as a result of loss of pre-existing selective pressures to maintain a large midface, with cultural adaptations to climate, feeding and lifestyle being possible factors in reducing these pressures and so allowing drift and other neutral processes to impact on midfacial form.

    “midfacial reduction may have arisen simply as a result of loss of pre-existing selective pressures to maintain a large midface, with cultural adaptations to climate, feeding and lifestyle being possible factors in reducing these pressures and so allowing drift and other neutral processes to impact on midfacial form”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Modern humans have a high degree of cranial variation exceeding that found in other primate species, with the face being an important contributor to this variation.

    “modern humans have a high degree of cranial variation exceeding that found in other primate species, with the face being an important contributor to this variation 75,76”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [75] Harvati, K. The Neanderthal taxonomic position: models of intra- and inter-specific craniofacial variation. J. Hum. Evol. 44, 107–132 (2003). source

      Not checked in the free run.

    • cites [76] Harvati, K., Frost, S. R. & McNulty, K. P. Neanderthal taxonomy reconsidered: implications of 3D primate models of intra- and interspecific differences. Proc. Natl Acad. Sci. USA 101, 1147–1152 (2004). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

    Premisecitation

    It has been argued, but is less likely, that brow ridges play a role in resisting loading of the jaws, the masticatory loading hypothesis.

    “it has also been argued, but is less likely, that they play a role in resisting loading of the jaws (masticatory loading hypothesis) 68”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [68] Russell, M. D. et al. The supraorbital torus: "A Most Remarkable Peculiarity". Curr. Anthropol. 26, 337–360 (1985). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Brow ridges have been considered to arise as a structural consequence of fitting a large face under a retracted frontal, the spatial hypothesis.

    “While brow ridges have been considered to arise as a structural consequence of fitting a large face under a retracted frontal (spatial hypothesis) 67”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [67] Moss, M. L. & Young, R. W. A functional approach to craniology. Am. J. Phys. Anthropol. 18, 281–292 (1960). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The earliest changes during the australopith to early Homo transition may have been driven in part by abiotic environmental factors and also by the social context.

    “The earliest changes during the australopith to early Homo transition may have been driven, in part, by abiotic environmental factors but also by the social context”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing). May combine two claims.

    Premisecitation

    H. sapiens facial skeletons show increased bite force relative to Middle Pleistocene hominins, which could be an advantage in fracturing hard objects.

    “it has been argued 71 that H. sapiens facial skeletons show increased bite force relative to MP hominins 72,73 , which could be an advantage in fracturing hard objects”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [71] Wroe, S., Ferrara, T. L., McHenry, C. R., Curnoe, D. & Chamoli, U. The craniomandibular mechanics of being human. Proc. R. Soc. Lond. B 277, 3579–3586 (2010). source

      Not checked in the free run.

    • cites [72] Anton, S. C. Neandertals and the anterior dental loading hypothesis: a biomechanical evaluation of bite force production. Kroeber Anthropological Society Papers 71–72, 67–76 (1990).

      Not checked in the free run.

    • cites [73] O’Connor, C. F., Franciscus, R. G. & Holton, N. E. Bite force production capability and efficiency in Neandertals and modern humans. Am. J. Phys. Anthropol. 127, 129–151 (2005). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The modern human cranium overall appears to be mainly shaped by neutral evolutionary processes, while the modern human face reflects both phylogenetic and environmental factors.

    “While the modern human cranium, overall, appears to be mainly shaped by neutral evolutionary processes [80][81][82] , the modern human face reflects both phylogenetic and environmental factors [81][82][83][84]”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [80] von Cramon-Taubadel, N. Evolutionary insights into global patterns of human cranial diversity: population history, climatic and dietary effects. J. Anthropol. Sci. 92, 43–77 (2014).

      Not checked in the free run.

    • cites [81] Harvati, K. & Weaver, T. D. Human cranial anatomy and the differential preservation of population history and climate signatures. Anat. Rec. A Discov. Mol. Cell. Evol. Biol. 288, 1225–1233 (2006). source

      Not checked in the free run.

    • cites [82] Hubbe, M., Hanihara, T. & Harvati, K. Climate signatures in the morphological differentiation of worldwide modern human populations. Anat. Rec. (Hoboken) 292, 1720–1733 (2009). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    While facial morphology carries a neutral genetic or population history signal, it is more strongly affected by climatic conditions than other parts of the cranium, especially in high latitude populations.

    “while facial morphology does carry a neutral genetic or population history signal, it is more strongly affected by climatic conditions than other parts of the cranium, especially in high latitude populations 81,82,83”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [81] Harvati, K. & Weaver, T. D. Human cranial anatomy and the differential preservation of population history and climate signatures. Anat. Rec. A Discov. Mol. Cell. Evol. Biol. 288, 1225–1233 (2006). source

      Not checked in the free run.

    • cites [82] Hubbe, M., Hanihara, T. & Harvati, K. Climate signatures in the morphological differentiation of worldwide modern human populations. Anat. Rec. (Hoboken) 292, 1720–1733 (2009). source

      Not checked in the free run.

    • cites [83] Reyes-Centeno, H., Ghirotto, S. & Harvati, K. Genomic validation of the differential preservation of population history in the human cranium. Am. J. Phys. Anthropol. 162, 170–179 (2017). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    The size of the jaws is restricted by the housing of teeth.

    “In addition, the size of the jaws is restricted by the housing of teeth.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Gene flow associated with migrations across the globe will likely affect the pace of evolutionary change.

    “It is also important to recognize the role of gene flow associated with migrations across the globe, which will likely affect the pace of evolutionary change.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing). May combine two claims.

    Interpretationcitation

    Because H. sapiens shows decreased ability to resist masticatory loading despite increased bite force, the increased bite force may simply be a by-product of facial reduction, driven by other factors.

    “because H. sapiens shows decreased ability to resist masticatory loading despite increased bite force, the increased bite force may simply be a by-product of facial reduction, driven by other factors 74”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [74] Godinho, R. M. et al. The biting performance of Homo sapiens and Homo heidelbergensis. J. Hum. Evol. 118, 56–71 (2018). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Integration, or covariation, among morphological units can be quantitated, enabling mathematical models that predict how changes of individual units may occur in response to changes in other units.

    “Integration, or covariation, among morphological units can be quantitated, enabling the development of mathematical models that predict how changes of individual units may occur in response to changes in other units 92 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [92] Conroy, G. C., Jolly, C. J., Cramer, D. & Kalb, J. E. Newly discovered fossil hominid skull from the Afar depression, Ethiopia. Nature 276, 67 (1978). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

    Premisecitation

    The large midface, chinless jaws and enlarged brow ridges of Middle Pleistocene hominins make up a suite of features adapted to masticatory or paramasticatory uses.

    “the large midface, chinless jaws and enlarged brow ridges of MP hominins make up a suite of features adapted to masticatory or paramasticatory uses 59,60,65,66”
    Quote in the paperNot a substantial claim0 of 4 sources checked
    • cites [59] Rak, Y. The Neanderthal: a new look at an old face. J. Hum. Evol. 15, 151–164 (1986). source

      Not checked in the free run.

    • cites [60] Demes, B. Another look at an old face: biomechanics of the Neandertal facial skeleton reconsidered. J. Hum. Evol. 16, 297–303 (1987). source

      Not checked in the free run.

    • cites [65] Gröning, F., Liu, J., Fagan, M. J. & O’Higgins, P. Why do humans have chins? Testing the mechanical significance of modern human symphyseal morphology with finite element analysis. Am. J. Phys. Anthropol. 144, 593–606 (2011). source

      Not checked in the free run.

    • cites [66] Pampush, J. D. & Daegling, D. J. The enduring puzzle of the human chin. Evol. Anthropol. 25, 20–35 (2016). source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationcitation

    A shift in eyebrow mobility could have enabled a wider range of subtler social signals, enhancing social communication.

    “such a shift in eyebrow mobility could have enabled a wider range of subtler social signals, enhancing social communication.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [87] Godinho, R. M., Spikins, P. & O’Higgins, P. Supraorbital morphology and social dynamics in human evolution. Nat. Ecol. Evol. 2, 956–961 (2018). source

      Not checked in the free run.

    • Rests on an assumption: Brow ridge reduction accompanied midfacial reduction.

  • May combine two claims.

    Premisecitation

    Bone growth centers are present in the craniofacial skeleton and are situated to optimize the organism's physiological requirements through integrating factors over time.

    “One aspect of this organization in the craniofacial skeleton is the presence of bone growth centers 22,55 , which are situated to optimize the organism's physiological requirements through the actions of integrating factors over time.”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [22] Ungar, P. S. & Sponheimer, M. The diets of early hominins. Science 334, 190–193 (2011). source

      Not checked in the free run.

    • cites [55] Lieberman, D. E. Speculations about the selective basis for modern human craniofacial form. Evol. Anthropol. 17, 55–68 (2008). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The mammalian skull is developmentally complex and a highly integrated structure.

    “The mammalian skull is developmentally complex and a highly integrated structure 91 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [91] Wood, B.A. & Boyle, E.K. Hominin taxic diversity: fact or fantasy? Am. J. Phys. Anthropol. 159, S37–S78 (2016). source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The modern human face is more sculpted and remodeled and has more complex topography than any other hominin face.

    “the modern human face is more sculpted and remodeled, has more complex topography than any other hominin face 16”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [16] Lacruz, R. S. et al. Facial morphogenesis of the earliest europeans. PLoS One 8, e65199 (2013). source

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Compared to modern humans, the region that most differs in Sima de los Huesos, H. heidelbergensis and Neanderthals is the nasal cavity itself, suggesting that reduction of this is the primary underlying cause of midfacial reduction in modern humans.

    “Compared to modern humans, the region that most differs is the nasal cavity itself, suggesting reduction of this is the primary underlying cause of midfacial reduction in modern humans.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Growth remodeling, meaning bone formation and bone resorption, is an integral process of craniofacial growth that relates to maintaining the shape and proportions of the face during development.

    “Growth remodeling (bone formation and bone resorption) is an integral process of craniofacial growth that relates to maintaining the shape and proportions of the face during development 94 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [94] Stringer, C. & Galway-Witham, J. Palaeoanthropology: on the origin of our species. Nature 546, 212 (2017). source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    The more gracile face potentially gained an ability to generate more diverse facial expressions, likely enhancing non-verbal communication.

    “potentially gaining an ability to generate more diverse facial expressions, likely enhancing non-verbal communication.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Interpretationnone given

    These new faces continued to evolve during challenges by their environment, impacted increasingly by culture and social factors.

    “These new faces continued to evolve during challenges by their environment, impacted increasingly by culture and social factors.”
    Quote in the paperNot a substantial claim
51 of 51

  • The paper relies on this without support.

    The human and chimpanzee/bonobo lineages shared a most recent common ancestor.

    “That the human and chimpanzee/bonobo lineages shared a most recent common ancestor is beyond dispute”

  • The paper relies on this without support.

    The last common ancestor of H. sapiens and other extinct taxa should predate the appearance of a modern face.

    “the LCA should predate the appearance of a modern face”

  • The paper relies on this without support.

    Brow ridge reduction accompanied midfacial reduction.

    “It is of interest in this regard that brow ridge reduction accompanied midfacial reduction.”

  • The paper relies on this without support.

    Biomolecular and mechanical signals trigger coordinated bone forming and bone resorbing activity during growth.

    “Such factors include biomolecular and mechanical signals that trigger coordinated bone forming and bone resorbing activity during growth (see Box 2).”

  • The paper relies on this without support.

    Growth remodeling can be determined by analysis of the distribution of depository and resorptive fields on bone surfaces due to the activities of osteoblasts and osteoclasts.

    “Growth remodeling can be determined by analysis of the distribution of depository and resorptive fields on bone surfaces due to the activities of osteoblasts and osteoclasts, respectively.”

  • The paper relies on this without support.

    Such developmental signatures are best characterized in sub-adult individuals.

    “Such developmental signatures are best characterized in sub-adult individuals.”
6 of 6

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Broken Hill 1 has conflicting Figure 3 panel labels

    Minor

    The text identifies Broken Hill 1 as Figure 3c, but the figure caption labels it as panel b; the caption also assigns panel b to Bodo.

  • Nanjing fossil has two reported ages

    Minor

    Table 1 gives Nanjing an age of approximately 500 Ka, while the Figure 3 caption dates it to approximately 400 Ka.

2 of 2

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. Bastir, M. in Biological Theory (ed. Schwartz, J.) 205–227 (in press).
  2. Kurihara, S., Enlow, D. H. & Rangel, R. D. Remodeling reversals in anterior parts of the human mandible and maxilla. Angle Orthod. 50, 98–106 (1980).

Cited by

Sorted by citations

Related

Authors
Lacruz, R. S., Stringer, C. B., Kimbel, W. H., Wood, B., Harvati, K., O’Higgins, P., Bromage, T. G., & Arsuaga, J.-L.
Affiliations
  • New York Consortium in Evolutionary Primatology (US)
  • Natural History Museum (GB)
  • Arizona State University (US)
  • George Washington University (US)
  • Senckenberg Centre for Human Evolution and Palaeoenvironment (DE)
  • University of York (GB)
  • New York University (US)
Corresponding author
Lacruz, Rodrigo S.
ORCID
Venue
Nature Ecology & Evolution
Publisher
Springer Science and Business Media LLC
Published
2019-04-15
Volume
3
Issue
5
Pages
726-736
ISSN
2397-334X (ISSN-L)
DOI
10.1038/s41559-019-0865-7
OpenAlex
W2936204499
Cited by
108
References
101
Citations by year
2026: 6 · 2025: 16 · 2024: 17 · 2023: 17 · 2022: 17 · 2021: 19 · 2020: 11 · 2019: 5
FWCI
16.67
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Ecology & Evolution (publishedVersion)
  • PubMed (publishedVersion)
  • White Rose Research Online (University of Leeds, The University of Sheffield, University of York) (submittedVersion)
  • Docta Complutense (Universidad Complutense de Madrid) (submittedVersion)
  • Zenodo (CERN European Organization for Nuclear Research) (submittedVersion, cc-by-nc-nd)
Funders
  • Fundación Ramón Areces
  • Deutsche Forschungsgemeinschaft (DFG‐FOR 2237, FOR2237)
Topics
  • Social Sciences › Anthropology › Pleistocene-Era Hominins and Archaeology
  • Physical Sciences › Mathematics › Geometry and Topology › Morphological variations and asymmetry
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Evolutionary Psychology and Human Behavior
Keywords
facial skeleton, fossil hominins, craniofacial morphology, facial growth, human origins
MeSH terms
Adaptation, Biological, Animals, Biological Evolution, Face, Humans, Hominidae, Genome, Human

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-10.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-10.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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