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Clark EG, Jenkins KM, Brodersen CR. Back to life: Techniques for developing high-quality 3D reconstructions of plants and animals from digitized specimens. PLoS One 2023; 18:e0283027. [PMID: 36989314 PMCID: PMC10058149 DOI: 10.1371/journal.pone.0283027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
Expanded use of 3D imaging in organismal biology and paleontology has substantially enhanced the ability to visualize and analyze specimens. These techniques have improved our understanding of the anatomy of many taxa, and the integration of downstream computational tools applied to 3D datasets have broadened the range of analyses that can be performed (e.g., finite element analyses, geometric morphometrics, biomechanical modeling, physical modeling using 3D printing). However, morphological analyses inevitably present challenges, particularly in fossil taxa where taphonomic or preservational artifacts distort and reduce the fidelity of the original morphology through shearing, compression, and disarticulation, for example. Here, we present a compilation of techniques to build high-quality 3D digital models of extant and fossil taxa from 3D imaging data using freely available software for students and educators. Our case studies and associated step-by-step supplementary tutorials present instructions for working with reconstructions of plants and animals to directly address and resolve common issues with 3D imaging data. The strategies demonstrated here optimize scientific accuracy and computational efficiency and can be applied to a broad range of taxa.
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Affiliation(s)
- Elizabeth G Clark
- Department of Environmental Science, Policy and Management, University of California Berkeley, Berkeley, California, United States of America
| | - Kelsey M Jenkins
- Department of Earth and Planetary Sciences, Yale University, New Haven, Connecticut, United States of America
| | - Craig R Brodersen
- School of the Environment, Yale University, New Haven, Connecticut, United States of America
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2
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Scott NA, Strauss A, Hublin JJ, Gunz P, Neubauer S. Covariation of the endocranium and splanchnocranium during great ape ontogeny. PLoS One 2018; 13:e0208999. [PMID: 30566462 PMCID: PMC6300334 DOI: 10.1371/journal.pone.0208999] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 11/28/2018] [Indexed: 12/25/2022] Open
Abstract
That great ape endocranial shape development persists into adolescence indicates that the splanchnocranium succeeds brain growth in driving endocranial development. However, the extent of this splanchnocranial influence is unknown. We applied two-block partial least squares analyses of Procrustes shape variables on an ontogenetic series of great ape crania to explore the covariation of the endocranium (the internal braincase) and splanchnocranium (face, or viscerocranium). We hypothesized that a transition between brain growth and splanchnocranial development in the establishment of final endocranial form would be manifest as a change in the pattern of shape covariation between early and adolescent ontogeny. Our results revealed a strong pattern of covariation between endocranium and splanchnocranium, indicating that chimpanzees, gorillas, and orangutans share a common tempo and mode of morphological integration from the eruption of the deciduous dentition onwards to adulthood: a reflection of elongating endocranial shape and continuing splanchnocranial prognathism. Within this overarching pattern, we noted that species variation exists in magnitude and direction, and that the covariation between the splanchnocranium and endocranium is somewhat weaker in early infancy compared to successive age groups. When correcting our covariation analyses for allometry, we found that an ontogenetic signal remains, signifying that allometric variation alone is insufficient to account for all endocranial-splanchnocranial developmental integration. Finally, we assessed the influence of the cranial base, which acts as the interface between the face and endocranium, on the shape of the vault using thin-plate spline warping. We found that not all splanchnocranial shape changes during development are tightly integrated with endocranial shape. This suggests that while the developmental expansion of the brain is the main driver of endocranial shape during early ontogeny, endocranial development from infancy onwards is moulded by the splanchnocranium in conjunction with the neurocranium.
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Affiliation(s)
- Nadia A. Scott
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz, Leipzig, Germany
- Konrad Lorenz Institute for Evolution and Cognition Research, Martinstrasse, Klosterneuburg, Austria
| | - André Strauss
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz, Leipzig, Germany
| | - Jean-Jacques Hublin
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz, Leipzig, Germany
| | - Philipp Gunz
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz, Leipzig, Germany
| | - Simon Neubauer
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz, Leipzig, Germany
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Lautenschlager S. Reconstructing the past: methods and techniques for the digital restoration of fossils. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160342. [PMID: 27853548 PMCID: PMC5098973 DOI: 10.1098/rsos.160342] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/08/2016] [Indexed: 05/24/2023]
Abstract
During fossilization, the remains of extinct organisms are subjected to taphonomic and diagenetic processes. As a result, fossils show a variety of preservational artefacts, which can range from small breaks and cracks, disarticulation and fragmentation, to the loss and deformation of skeletal structures and other hard parts. Such artefacts can present a considerable problem, as the preserved morphology of fossils often forms the basis for palaeontological research. Phylogenetic and taxonomic studies, inferences on appearance, ecology and behaviour and functional analyses of fossil organisms strongly rely on morphological information. As a consequence, the restoration of fossil morphology is often a necessary prerequisite for further analyses. Facilitated by recent computational advances, virtual reconstruction and restoration techniques offer versatile tools to restore the original morphology of fossils. Different methodological steps and approaches, as well as software are outlined and reviewed here, and advantages and disadvantages are discussed. Although the complexity of the restorative processes can introduce a degree of interpretation, digitally restored fossils can provide useful morphological information and can be used to obtain functional estimates. Additionally, the digital nature of the restored models can open up possibilities for education and outreach and further research.
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Crevecoeur I, Brooks A, Ribot I, Cornelissen E, Semal P. Late Stone Age human remains from Ishango (Democratic Republic of Congo): New insights on Late Pleistocene modern human diversity in Africa. J Hum Evol 2016; 96:35-57. [PMID: 27343771 DOI: 10.1016/j.jhevol.2016.04.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 04/08/2016] [Accepted: 04/19/2016] [Indexed: 12/11/2022]
Abstract
Although questions of modern human origins and dispersal are subject to intense research within and outside Africa, the processes of modern human diversification during the Late Pleistocene are most often discussed within the context of recent human genetic data. This situation is due largely to the dearth of human fossil remains dating to the final Pleistocene in Africa and their almost total absence from West and Central Africa, thus limiting our perception of modern human diversification within Africa before the Holocene. Here, we present a morphometric comparative analysis of the earliest Late Pleistocene modern human remains from the Central African site of Ishango in the Democratic Republic of Congo. The early Late Stone Age layer (eLSA) of this site, dated to the Last Glacial Maximum (25-20 Ky), contains more than one hundred fragmentary human remains. The exceptional associated archaeological context suggests these remains derived from a community of hunter-fisher-gatherers exhibiting complex social and cognitive behaviors including substantial reliance on aquatic resources, development of fishing technology, possible mathematical notations and repetitive use of space, likely on a seasonal basis. Comparisons with large samples of Late Pleistocene and early Holocene modern human fossils from Africa and Eurasia show that the Ishango human remains exhibit distinctive characteristics and a higher phenotypic diversity in contrast to recent African populations. In many aspects, as is true for the inner ear conformation, these eLSA human remains have more affinities with Middle to early Late Pleistocene fossils worldwide than with extant local African populations. In addition, cross-sectional geometric properties of the long bones are consistent with archaeological evidence suggesting reduced terrestrial mobility resulting from greater investment in and use of aquatic resources. Our results on the Ishango human remains provide insights into past African modern human diversity and adaptation that are consistent with genetic theories about the deep sub-structure of Late Pleistocene African populations and their complex evolutionary history of isolation and diversification.
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Affiliation(s)
- I Crevecoeur
- UMR 5199 PACEA, CNRS, Université de Bordeaux, Pessac, France.
| | - A Brooks
- Department of Anthropology, George Washington University, Washington DC, USA
| | - I Ribot
- Département d'Anthropologie, Université de Montréal, Montréal, Canada
| | - E Cornelissen
- Culturele Antropologie/Prehistorie en Archeologie, Koninklijk Museum voor Midden-Afrika (KMMA), Tervuren, Belgium
| | - P Semal
- Scientific Service of Heritage, Royal Belgian Institute of Natural Sciences (RBINS), Brussels, Belgium
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Grine FE. The Late Quaternary Hominins of Africa: The Skeletal Evidence from MIS 6-2. AFRICA FROM MIS 6-2 2016. [DOI: 10.1007/978-94-017-7520-5_17] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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6
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Reyes-Centeno H, Hubbe M, Hanihara T, Stringer C, Harvati K. Testing modern human out-of-Africa dispersal models and implications for modern human origins. J Hum Evol 2015; 87:95-106. [DOI: 10.1016/j.jhevol.2015.06.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 03/02/2015] [Accepted: 06/14/2015] [Indexed: 11/26/2022]
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Freidline SE, Gunz P, Hublin JJ. Ontogenetic and static allometry in the human face: contrasting Khoisan and Inuit. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 158:116-31. [PMID: 26146938 DOI: 10.1002/ajpa.22759] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 04/14/2015] [Accepted: 04/14/2015] [Indexed: 12/17/2022]
Abstract
OBJECTIVES Regional differences in modern human facial features are present at birth, and ontogenetic allometry contributes to variation in adults. However, details regarding differential rates of growth and timing among regional groups are lacking. We explore ontogenetic and static allometry in a cross-sectional sample spanning Africa, Europe and North America, and evaluate tempo and mode in two regional groups with very different adult facial morphology, the Khoisan and Inuit. MATERIALS AND METHODS Semilandmark geometric morphometric methods, multivariate statistics and growth simulations were used to quantify and compare patterns of facial growth and development. RESULTS Regional-specific facial morphology develops early in ontogeny. The Inuit has the most distinct morphology and exhibits heterochronic differences in development compared to other regional groups. Allometric patterns differ during early postnatal development, when significant increases in size are coupled with large amounts of shape changes. All regional groups share a common adult static allometric trajectory, which can be attributed to sexual dimorphism, and the corresponding allometric shape changes resemble developmental patterns during later ontogeny. DISCUSSION The amount and pattern of growth and development may not be shared between regional groups, indicating that a certain degree of flexibility is allowed for in order to achieve adult size. In early postnatal development the face is less constrained compared to other parts of the cranium allowing for greater evolvability. The early development of region-specific facial features combined with heterochronic differences in timing or rate of growth, reflected in differences in facial size, suggest different patterns of postnatal growth.
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Affiliation(s)
- Sarah E Freidline
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, 04103, Germany
| | - Philipp Gunz
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, 04103, Germany
| | - Jean-Jacques Hublin
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, 04103, Germany
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Tryon CA, Crevecoeur I, Faith JT, Ekshtain R, Nivens J, Patterson D, Mbua EN, Spoor F. Late Pleistocene age and archaeological context for the hominin calvaria from GvJm-22 (Lukenya Hill, Kenya). Proc Natl Acad Sci U S A 2015; 112:2682-7. [PMID: 25730861 PMCID: PMC4352791 DOI: 10.1073/pnas.1417909112] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Kenya National Museums Lukenya Hill Hominid 1 (KNM-LH 1) is a Homo sapiens partial calvaria from site GvJm-22 at Lukenya Hill, Kenya, associated with Later Stone Age (LSA) archaeological deposits. KNM-LH 1 is securely dated to the Late Pleistocene, and samples a time and region important for understanding the origins of modern human diversity. A revised chronology based on 26 accelerator mass spectrometry radiocarbon dates on ostrich eggshells indicates an age range of 23,576-22,887 y B.P. for KNM-LH 1, confirming prior attribution to the Last Glacial Maximum. Additional dates extend the maximum age for archaeological deposits at GvJm-22 to >46,000 y B.P. (>46 kya). These dates are consistent with new analyses identifying both Middle Stone Age and LSA lithic technologies at the site, making GvJm-22 a rare eastern African record of major human behavioral shifts during the Late Pleistocene. Comparative morphometric analyses of the KNM-LH 1 cranium document the temporal and spatial complexity of early modern human morphological variability. Features of cranial shape distinguish KNM-LH 1 and other Middle and Late Pleistocene African fossils from crania of recent Africans and samples from Holocene LSA and European Upper Paleolithic sites.
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Affiliation(s)
- Christian A Tryon
- Department of Anthropology, Harvard University, Cambridge, MA 02138;
| | - Isabelle Crevecoeur
- Unité Mixte de Recherche 5199, de la Préhistoire à l'Actuel: Culture, Environnement, et Anthropologie, Centre National de la Recherche Scientifique, Université de Bordeaux, 33615 Talence, France
| | - J Tyler Faith
- Archaeology Program, School of Social Science, University of Queensland, Brisbane, QLD 4072, Australia
| | - Ravid Ekshtain
- Department of Anthropology, Harvard University, Cambridge, MA 02138
| | - Joelle Nivens
- Department of Anthropology, New York University, New York, NY 10003
| | - David Patterson
- Center for the Advanced Study of Hominid Paleobiology, Department of Anthropology, The George Washington University, Washington, DC 20052
| | - Emma N Mbua
- National Museums of Kenya, Nairobi, Kenya 00100
| | - Fred Spoor
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, D-04103, Leipzig, Germany; and Department of Cell and Developmental Biology, University College London, WC1E 6BT London, United Kingdom
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9
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Virtual Reconstruction of Modern and Fossil Hominoid Crania: Consequences of Reference Sample Choice. Anat Rec (Hoboken) 2015; 298:827-41. [DOI: 10.1002/ar.23104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 10/30/2014] [Indexed: 11/07/2022]
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10
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Weber GW. Virtual Anthropology. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2014; 156 Suppl 59:22-42. [DOI: 10.1002/ajpa.22658] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gerhard W. Weber
- Department of Anthropology; University of Vienna; A-1090 Vienna Austria
- Core Facility for Micro-Computed Tomography; University of Vienna; A-1090 Vienna Austria
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11
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Cunningham JA, Rahman IA, Lautenschlager S, Rayfield EJ, Donoghue PCJ. A virtual world of paleontology. Trends Ecol Evol 2014; 29:347-57. [PMID: 24821516 DOI: 10.1016/j.tree.2014.04.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 03/26/2014] [Accepted: 04/08/2014] [Indexed: 11/28/2022]
Abstract
Computer-aided visualization and analysis of fossils has revolutionized the study of extinct organisms. Novel techniques allow fossils to be characterized in three dimensions and in unprecedented detail. This has enabled paleontologists to gain important insights into their anatomy, development, and preservation. New protocols allow more objective reconstructions of fossil organisms, including soft tissues, from incomplete remains. The resulting digital reconstructions can be used in functional analyses, rigorously testing long-standing hypotheses regarding the paleobiology of extinct organisms. These approaches are transforming our understanding of long-studied fossil groups, and of the narratives of organismal and ecological evolution that have been built upon them.
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Affiliation(s)
- John A Cunningham
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
| | - Imran A Rahman
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
| | - Stephan Lautenschlager
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK
| | - Emily J Rayfield
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK.
| | - Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK.
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12
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Freidline SE, Gunz P, Harvati K, Hublin JJ. Evaluating developmental shape changes in Homo antecessor subadult facial morphology. J Hum Evol 2013; 65:404-23. [PMID: 23998458 DOI: 10.1016/j.jhevol.2013.07.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 07/25/2013] [Accepted: 07/25/2013] [Indexed: 11/26/2022]
Abstract
The fossil ATD6-69 from Atapuerca, Spain, dated to ca. 900 ka (thousands of years ago) has been suggested to mark the earliest appearance of modern human facial features. However, this specimen is a subadult and the interpretation of its morphology remains controversial, because it is unclear how developmental shape changes would affect the features that link ATD6-69 to modern humans. Here we analyze ATD6-69 in an evolutionary and developmental context. Our modern human sample comprises cross-sectional growth series from four populations. The fossil sample covers human specimens from the Pleistocene to the Upper Paleolithic, and includes several subadult Early Pleistocene humans and Neanderthals. We digitized landmarks and semilandmarks on surface and CT scans and analyzed the Procrustes shape coordinates using multivariate statistics. Ontogenetic allometric trajectories and developmental simulations were employed in order to identify growth patterns and to visualize potential adult shapes of ATD6-69. We show that facial differences between modern and archaic humans are not exclusively allometric. We find that while postnatal growth further accentuates the differences in facial features between Neanderthals and modern humans, those features that have been suggested to link ATD6-69's morphology to modern humans would not have been significantly altered in the course of subsequent development. In particular, the infraorbital depression on this specimen would have persisted into adulthood. However, many of the facial features that ATD6-69 shares with modern humans can be considered to be part of a generalized pattern of facial architecture. Our results present a complex picture regarding the polarity of facial features and demonstrate that some modern human-like facial morphology is intermittently present in Middle Pleistocene humans. We suggest that some of the facial features that characterize recent modern humans may have developed multiple times in human evolution.
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Affiliation(s)
- Sarah E Freidline
- Max Planck Institute for Evolutionary Anthropology, Department of Human Evolution, Deutscher Platz 6, Leipzig 04103, Germany; City University of New York Graduate School, 365 Fifth Avenue, New York, NY 10016, USA; New York Consortium in Evolutionary Primatology, USA; Paleoanthropology, Department of Early Prehistory and Quaternary Ecology, Eberhard Karls Universität Tübingen and Senckenberg Center for Human Evolution and Paleoecology, Rümelinstrasse 23, 72070 Tübingen, Germany.
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Senck S, Coquerelle M, Weber GW, Benazzi S. Virtual Reconstruction of Very Large Skull Defects Featuring Partly and Completely Missing Midsagittal Planes. Anat Rec (Hoboken) 2013; 296:745-58. [DOI: 10.1002/ar.22693] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 02/22/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Sascha Senck
- Department of Anthropology; University of Vienna; Althanstrasse 14, 1090 Vienna Austria
| | - Michael Coquerelle
- Department of Paleobiology; Paleoanthropology group; Museo Nacional de Ciencias Naturales (MNCM-CSIC), C/José Gutiérrez Abascal 2 28006 Madrid Spain
| | - Gerhard W. Weber
- Department of Anthropology; University of Vienna; Althanstrasse 14, 1090 Vienna Austria
| | - Stefano Benazzi
- Department of Human Evolution; Max Planck Institute for Evolutionary Anthropology; Deutscher Platz 6 Leipzig 04103 Germany
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15
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Gunz P, Bulygina E. The Mousterian child from Teshik-Tash is a Neanderthal: A geometric morphometric study of the frontal bone. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2012; 149:365-79. [DOI: 10.1002/ajpa.22133] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 07/23/2012] [Indexed: 01/10/2023]
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Baab KL, McNulty KP, Rohlf FJ. The shape of human evolution: A geometric morphometrics perspective. Evol Anthropol 2012; 21:151-65. [DOI: 10.1002/evan.21320] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Neubauer S, Gunz P, Weber GW, Hublin JJ. Endocranial volume of Australopithecus africanus: new CT-based estimates and the effects of missing data and small sample size. J Hum Evol 2012; 62:498-510. [PMID: 22365336 DOI: 10.1016/j.jhevol.2012.01.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 01/12/2012] [Accepted: 01/19/2012] [Indexed: 11/29/2022]
Abstract
Estimation of endocranial volume in Australopithecus africanus is important in interpreting early hominin brain evolution. However, the number of individuals available for investigation is limited and most of these fossils are, to some degree, incomplete and/or distorted. Uncertainties of the required reconstruction ('missing data uncertainty') and the small sample size ('small sample uncertainty') both potentially bias estimates of the average and within-group variation of endocranial volume in A. africanus. We used CT scans, electronic preparation (segmentation), mirror-imaging and semilandmark-based geometric morphometrics to generate and reconstruct complete endocasts for Sts 5, Sts 60, Sts 71, StW 505, MLD 37/38, and Taung, and measured their endocranial volumes (EV). To get a sense of the reliability of these new EV estimates, we then used simulations based on samples of chimpanzees and humans to: (a) test the accuracy of our approach, (b) assess missing data uncertainty, and (c) appraise small sample uncertainty. Incorporating missing data uncertainty of the five adult individuals, A. africanus was found to have an average adult endocranial volume of 454-461 ml with a standard deviation of 66-75 ml. EV estimates for the juvenile Taung individual range from 402 to 407 ml. Our simulations show that missing data uncertainty is small given the missing portions of the investigated fossils, but that small sample sizes are problematic for estimating species average EV. It is important to take these uncertainties into account when different fossil groups are being compared.
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Affiliation(s)
- Simon Neubauer
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
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Freidline S, Gunz P, Janković I, Harvati K, Hublin J. A comprehensive morphometric analysis of the frontal and zygomatic bone of the Zuttiyeh fossil from Israel. J Hum Evol 2012; 62:225-41. [DOI: 10.1016/j.jhevol.2011.11.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 10/25/2011] [Accepted: 11/08/2011] [Indexed: 11/16/2022]
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Gunz P, Neubauer S, Golovanova L, Doronichev V, Maureille B, Hublin JJ. A uniquely modern human pattern of endocranial development. Insights from a new cranial reconstruction of the Neandertal newborn from Mezmaiskaya. J Hum Evol 2012; 62:300-13. [PMID: 22221766 DOI: 10.1016/j.jhevol.2011.11.013] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 10/20/2011] [Accepted: 11/24/2011] [Indexed: 11/16/2022]
Abstract
The globular braincase of modern humans is distinct from all fossil human species, including our closest extinct relatives, the Neandertals. Such adult shape differences must ultimately be rooted in different developmental patterns, but it is unclear at which point during ontogeny these group characteristics emerge. Here we compared internal shape changes of the braincase from birth to adulthood in Neandertals (N = 10), modern humans (N = 62), and chimpanzees (N = 62). Incomplete fossil specimens, including the two Neandertal newborns from Le Moustier 2 and Mezmaiskaya, were reconstructed using reference-based estimation methods. We used 3D geometric morphometrics to statistically compare shapes of virtual endocasts extracted from computed-tomographic scans. Throughout the analysis, we kept track of possible uncertainties due to the missing data values and small fossil sample sizes. We find that some aspects of endocranial development are shared by the three species. However, in the first year of life, modern humans depart from this presumably ancestral pattern of development. Newborn Neandertals and newborn modern humans have elongated braincases, and similar endocranial volumes. During a 'globularization-phase' modern human endocasts change to the globular shape that is characteristic for Homo sapiens. This phase of early development is unique to modern humans, and absent from chimpanzees and Neandertals. Our results support the notion that Neandertals and modern humans reach comparable adult brain sizes via different developmental pathways. The differences between these two human groups are most prominent directly after birth, a critical phase for cognitive development.
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Affiliation(s)
- Philipp Gunz
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Deutscher Platz 6, D-04103 Leipzig, Germany.
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Neubauer S, Gunz P, Hublin JJ. Endocranial shape changes during growth in chimpanzees and humans: a morphometric analysis of unique and shared aspects. J Hum Evol 2010; 59:555-66. [PMID: 20727571 DOI: 10.1016/j.jhevol.2010.06.011] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 06/26/2010] [Accepted: 06/27/2010] [Indexed: 12/26/2022]
Abstract
Compared to our closest living and extinct relatives, humans have a large, specialized, and complex brain embedded in a uniquely shaped braincase. Here, we quantitatively compare endocranial shape changes during ontogeny in humans and chimpanzees. Identifying shared and unique aspects in developmental patterns of these two species can help us to understand brain evolution in the hominin lineage. Using CT scans of 58 humans and 60 chimpanzees varying in age from birth to adulthood, we generated virtual endocasts to measure and analyze 29 three-dimensional endocranial landmarks and several hundred semilandmarks on curves and the endocranial surface; these data were then analyzed using geometric morphometric methods. The ontogenetic shape trajectories are nonlinear for both species, which indicates several developmental phases. Endocranial shape is already distinct at birth and there is no overlap between the two species throughout ontogeny. While some aspects of the pattern of endocranial shape change are shared between humans and chimpanzees, the shape trajectories differ substantially directly after birth until the eruption of the deciduous dentition: in humans but not in chimpanzees, the parietal and cerebellar regions expand relatively (contributing to neurocranial globularity) and the cranial base flexes within the first postnatal year when brain growth rates are high. We show that the shape changes associated with this early "globularization phase" are unique to humans and do not occur in chimpanzees before or after birth.
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Affiliation(s)
- Simon Neubauer
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig, Germany.
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Harvati K, Hublin JJ, Gunz P. Evolution of middle-late Pleistocene human cranio-facial form: a 3-D approach. J Hum Evol 2010; 59:445-64. [PMID: 20708775 DOI: 10.1016/j.jhevol.2010.06.005] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Revised: 05/24/2010] [Accepted: 04/08/2010] [Indexed: 11/20/2022]
Abstract
The classification and phylogenetic relationships of the middle Pleistocene human fossil record remains one of the most intractable problems in paleoanthropology. Several authors have noted broad resemblances between European and African fossils from this period, suggesting a single taxon ancestral to both modern humans and Neanderthals. Others point out 'incipient' Neanderthal features in the morphology of the European sample and have argued for their inclusion in the Neanderthal lineage exclusively, following a model of accretionary evolution of Neanderthals. We approach these questions using geometric morphometric methods which allow the intuitive visualization and quantification of features previously described qualitatively. We apply these techniques to evaluate proposed cranio-facial 'incipient' facial, vault, and basicranial traits in a middle-late Pleistocene European hominin sample when compared to a sample of the same time depth from Africa. Some of the features examined followed the predictions of the accretion model and relate the middle Pleistocene European material to the later Neanderthals. However, although our analysis showed a clear separation between Neanderthals and early/recent modern humans and morphological proximity between European specimens from OIS 7 to 3, it also shows that the European hominins from the first half of the middle Pleistocene still shared most of their cranio-facial architecture with their African contemporaries.
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Affiliation(s)
- Katerina Harvati
- Department of Early Prehistory and Quaternary Ecology and Senckenberg Center for Human Evolution and Paleoecology, Eberhard Karls Universität Tübingen, Rümelinstr. 23, 72070 Tübingen, Baden-Württenberg, Germany.
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