Abstract
Cranial anatomical features play a prominent part in the definition of extinct Homo taxa and in species identification in fossils. Thus, knowledge of cranial morphology considered within its geochronological framework is essential to the understanding of the evolution, chronology, and dispersal of the genus Homo. The brain is also a valuable object of study for research on human evolution, because of features such as its large size and a high encephalization quotient in some Homo species, as well as the complexity of human cognition. However, the joint evolution of endo- and ectocranial anatomies is still little studied, and landmarks representing cerebral anatomy rather than inner cranial bone anatomy are still rarely used. This exploratory piece of research examines endo- and ectocranial profiles in samples representing 3 Homo taxa: Homo sapiens (fossil and recent specimens), Homo erectus, and Homo neanderthalensis. We used 2D geometric morphometrics to analyze the shape of the endo- and ectocranial vaults, as well as the relationships between selected anatomical features such as the extension of lobes and bones. The shapes of the vaults were computed using both fixed landmarks and sliding semilandmarks. The fixed landmarks used for the endocranium were chosen in order to represent cerebral anatomy, in that they are defined by the imprints left by brain structures on the inner bone surface of the skull, and not by bony structures such as the inferior side of cranial sutures. Among other results, we have shown or confirmed specific features in the shape of the endocranium in Homo sapiens, as well as a few differences in the patterns of interplay between lobes and bones. These data, and any further results obtained with larger samples, may provide new insights into the development of the endocranial anatomical pattern in Homo sapiens and of its variability.
Résumé
Les caractères anatomiques crâniens jouent un rôle important dans la définition des espèces fossiles du genre Homo et dans l’identification taxonomique de spécimens fossiles. Ainsi, la connaissance de la morphologie crânienne, considérée dans son cadre géochronologique, est essentielle à la compréhension de l’évolution, de la chronologie et de la dispersion du genre Homo. Le cerveau est lui aussi un objet précieux pour la recherche sur l’évolution humaine. Des caractéristiques telles que la taille importante du cerveau et le quotient d’encéphalisation particulièrement élevé chez des espèces du genre Homo, ainsi que l’évolution de la cognition complexe humaine, expliquent l’intérêt accordé au cerveau dans les sciences de l’évolution. Cependant, la covariation des morphologies exo- et endocrâniennes et son évolution restent peu étudiées, et l’utilisation pour l’étude de l’endocrâne de points repères liés à l’anatomie cérébrale plutôt qu’à l’anatomie de la table osseuse interne reste rare. La présente étude explore cette problématique au travers de l’examen des profils exo- et endocrâniens dans des échantillons représentant trois espèces du genre Homo: Homo sapiens (spécimens fossiles et récents), Homo erectus et Homo neanderthalensis. Nous avons analysé la forme des voûtes exo- et endocrâniennes, ainsi que les relations entre des caractères anatomiques choisis, par la morphométrie géométrique en deux dimensions. La forme des voûtes a été digitalisée à l’aide de landmarks et de semi-landmarks. Les landmarks utilisés pour l’endocrâne ont été choisis de manière à représenter l’anatomie cérébrale et sont définis grâce aux empreintes causées par les structures anatomiques du cerveau sur la table interne de l’os crânien, et non grâce à des structures osseuses telles que la face inférieure des sutures crâniennes. Nos résultats montrent notamment des spécificités dans la conformation de l’endocrâne chez H. sapiens et de légères différences interspécifiques dans les interactions entre os et lobes. Ces données, ainsi que de futurs résultats sur de plus larges échantillons, pourront offrir de nouvelles perspectives quant au développement des schémas anatomiques de l’endocrâne propres à H. sapiens et de leur variabilité.
Article PDF
Similar content being viewed by others
References
Lieberman DE (2011) The evolution of the human head. Harvard University Press, 768 p
Neubauer S, Hublin JJ (2012) The evolution of human brain development. Evol Biol 39:568–86
Lestrel PE, Ohtsuki F, Wolfe CA (2010) Cranial vault shape in fossil hominids: Fourier descriptors in norma lateralis. Homo 61:287–313
Weaver TD (2009) The meaning of Neandertal skeletal morphology. Proc Natl Acad Sci 106:16028–33
Falk D (2007) Evolution of the primate brain. In: Henke W, Tattersall I (eds) Handbook of palaeoanthropology. Springer, New York, 2069 p
Zollikofer CP, Ponce de León MS, Lieberman DE, et al (2005) Virtual cranial reconstruction of Sahelanthropus tchadensis. Nature 434:755–9
Antón S, Spoor F, Fellman CD, Swisher CC (2007) Defining Homo erectus: size considered. In: Henke W, Tattersall I (eds) Handbook of palaeoanthropology. Springer, New York, 2069 p
Rightmire GP (2013) Homo erectus and Middle Pleistocene Hominins: Brain size, skull form, and species recognition. J Hum Evol 65:223–52
Rightmire GP (2007) Later Middle Pleistocene Homo. In: Henke W, Tattersall I (eds) Handbook of palaeoanthropology. Springer, New York, 2069 p
Bookstein F, Schäfer K, Prossinger H, et al (1999) Comparing frontal cranial profiles in archaic and modern Homo by morphometric analysis. Anat Rec 257:217–24
Tattersall I, Schwartz JH (2008) The morphological distinctiveness of Homo sapiens and its recognition in the fossil record: clarifying the problem. Evol Anthropol 17:49–54
Moss ML, Young RW (1960) A functional approach to craniology. Am J Phys Anthropol 18:281–92
Richtsmeier JT, Aldridge K, Leon VBDE, et al (2006) Phenotypic integration of neurocranium and brain. J Exp Zool (Mol Dev Evol) 378:360–78
Barton R (2012) Embodied cognitive evolution and the cerebellum. Philosophical transactions of the Royal Society of London. Phil Trans R Soc B 367:2097–107
Rapoport SI (1999) How did the human brain evolve? A proposal based on new evidence from in vivo brain imaging during attention and ideation. Brain Res Bull 50:149–65
Weaver AH (2005) Reciprocal evolution of the cerebellum and neocortex in fossil humans. Proc Natl Acad Sci USA 102:3576–80
Flinn MV, Geary DC, Ward CV (2005) Ecological dominance, social competition, and coalitionary arms races. Evol Hum Behav 26:10–46
Falk D (1991) 3.5 million years of hominid brain evolution. Semin Neurosci 3:409–16
Kappelman J (1996) The evolution of body mass and relative brain size in fossil hominids. J Hum Evol 30:243–76
Roth G, Dicke U (2005) Evolution of the brain and intelligence. Trends Cogn Sci 9:250–7
Balzeau A, Holloway RL, Grimaud-Hervé D (2012) Variations and asymmetries in regional brain surface in the genus Homo. J Hum Evol 62:696–706
Saban R (1984) Anatomie et évolution des veines méningées chez les hommes fossiles. ENSB–CTHS, Paris
Balzeau A, Grimaud-Hervé D, Gilissen E (2011) Where are inion and endinion? Variations of the exo- and endocranial morphology of the occipital bone during hominin evolution. J Hum Evol 61:488–502
Grimaud-Hervé D (1997) L’évolution de l’encéphale chez Homo erectus et Homo sapiens, exemples de l’Asie et l’Europe. CNRS Éditions, Paris
Holloway R, Broadfield D, Yuan M (2004) The human fossil record, volume three: brain endocasts, the paleoneurological evidence. In: Schwartz J, Tattersall I (eds). Wiley-Liss, Hoboken
Athreya S (2012) The frontal bone in the genus Homo: a survey of functional and phylogenetic sources of variation. J Anthropol Sci 90:59–80
Stringer C (2012) The status of Homo heidelbergensis (Schoetensack 1908). Evol Anthropol 21:101–7
Arsuaga JL, Martínez I, Gracia A, Lorenzo C (1997) The sima de los huesos crania (Sierra de Atapuerca, Spain). A comparative study. J Hum Evol 33:219–81
Rak Y, Hylander W, Quam R, et al (2011) American Journal of Physical Anthropology abstracts, The problematic hypodigm of Homo heidelbergensis. Am J Phys Anthropol 152:247
Webster M, Sheets HD (2010) A practical introduction to landmark-based geometric morphometrics. Paleontol Soc Papers 16:163–88
Rohlf FJ (2008) TpsRelw v1.46. Department of ecology and evolution, State University of New York. http://life.bio.sunysb.edu. morph/
Rohlf FJ (2009) TpsDig v2.14. Department of ecology and evolution, State University of New York. http://life.bio.sunysb.edu. morph/
Bookstein FL (1991) Morphometric tools for landmark data: geometry and biology. Cambridge, New York
Gunz P, Mitteroecker P (2013) Semilandmarks: a method for quantifying curves and surfaces. Hystrix 24:103–9
Dryden IL (2013) Shapes: statistical shape analysis. R Package version 1.1-8. http://cran.r-project.org/package=shapes
Schlager S (2013) Morpho: calculations and visualisations related to geometric morphometrics. R Package version 0.25-1. http:// cran.r-project.org/package=Morpho
Sheets HD (2001) Integrated morphometrics package. Dept. of physics, Canisius College, 2001 Main St., Buffalo, NY 14208. http://www.canisius.edu/~sheets/morphsoft.html
Adams DC, Otarolla-Castillo E (2013) Geomorph: an R Package for the collection and analysis of geometric morphometric shape data. Methods Ecol Evol 4:393–99
Rohlf FJ, Corti M (2000) Use of two-block partial least-squares to study covariation in shape. Syst Biol 49:740–53
Delson E, Harvati K, Reddy D, et al (2001) The Sambungmacan 3 Homo erectus calvaria: a comparative morphometric and morphological analysis. Anat Rec 397:380–97
Márquez S, Mowbray K, Sawyer GJ, et al (2001) New fossil hominid Calvaria from Indonesia — Sambungmacan 3. Anat Rec 262:344–68
Broadfield DC, Holloway RL, Mowbray K, et al (2001) Endocast of Sambungmacan 3 (Sm 3): a new Homo erectus from Indonesia. Anat Rec 262:369–79
Balzeau A (2007) Nouvelles données sur les caractéristiques morphologiques immatures du crâne chez les Homo erectus asiatiques. Bull Mem Soc Anthropol Paris 19:169–85
Athreya S (2009) A comparative study of frontal bone morphology among Pleistocene Hominin fossil groups. J Hum Evol 57:786–804
Semendeferi K, Damasio H, Frank R (1997) The evolution of the frontal lobes: a volumetric analysis based on three-dimensional reconstructions of magnetic resonance scans of human and ape brains. J Hum Evol 32:375–88
Bruner E (2004) Geometric morphometrics and paleoneurology: brain shape evolution in the genus Homo. J Hum Evol 47:279–303
Gunz P, Neubauer S, Golovanova L, et al (2012) A uniquely modern human pattern of endocranial development. Insights from a new cranial reconstruction of the Neandertal newborn from Mezmaiskaya. J Hum Evol 62:300–13
Bookstein FL, Gunz P, Mitteroecker P, et al (2003) Cranial integration in Homo: singular warps analysis of the mid-sagittal plane in ontogeny and evolution. J Hum Evol 44:167–87
Lieberman DE, McBratney BM, Krovitz G (2002) The evolution and development of cranial form in Homo sapiens. Proceedings of the National Academy of sciences of the United States of America 99:134–39
Balzeau A, Badawi-Fayad J (2005) La morphologie externe et interne de la région supraorbitale est-elle corrélée à des contraintes biomécaniques ? Analyses structurales des populations d’Homo sapiens d’Afalou Bou Rhummel (Algérie) et de Taforalt (Maroc). BMSAP 17:185–97
Schulting R (1999) Nouvelles dates AMS à Téviec et Hoëdic (Quiberon, Morbihan) [Rapport préliminaire]. Bull Soc Prehist Fr 96:203–7
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Albessard, L., Grimaud-Hervé, D. & Balzeau, A. Evolution of cranial and endocranial profiles in Homo species: A study in 2D geometric morphometrics. BMSAP 28, 118–131 (2016). https://doi.org/10.1007/s13219-016-0161-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s13219-016-0161-x