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1.
Sci Rep ; 12(1): 13826, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35970916

RESUMO

This study assessed the regional diversity of the human cranial form by using geometric homologous models based on scanned data from 148 ethnic groups worldwide. This method adopted a template-fitting technique for a nonrigid transformation via the iterative closest point algorithm to generate the homologous meshes. Through the application of principal component analysis to 342 sampled homologous models, the largest variation was detected in overall size, and small South Asian crania were clearly verified. The next greatest diversity was found in the length/breadth proportion of the neurocranium, which showed the contrast between the elongated crania of Africans and the globular crania of Northeast Asians. Notably, this component was slightly correlated with the facial profile. Well-known facial features, such as the forward projection of the cheek among Northeast Asians and compaction of the European maxilla, were reconfirmed. These facial variations were highly correlated with the calvarial outline, particularly the degree of frontal and occipital inclines. An allometric pattern was detected in facial proportions in relation to overall cranial size; in larger crania, the facial profiles tend to be longer and narrower, as demonstrated among many American natives and Northeast Asians. Although our study did not include data on environmental variables that are likely to affect cranial morphology, such as climate or dietary conditions, the large datasets of homologous cranial models will be usefully available for seeking various attributions to phenotypic skeletal characteristics.


Assuntos
Face , Crânio , Pesos e Medidas Corporais , Clima , Face/anatomia & histologia , Humanos , Análise de Componente Principal , Crânio/anatomia & histologia
2.
J Hum Evol ; 163: 103119, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35026677

RESUMO

The Late Middle Pleistocene hominin fossils from the Xujiayao site in northern China have been closely studied in light of their morphological variability. However, all previous studies have focused on separated cranial fragments. Here, we report the first reconstruction of a fairly complete posterior cranium, Xujiayao 6 (XJY 6), confidently dated to ∼200-160 ka, which facilitated an assessment of its overall cranial size. XJY 6 was reconstructed from three of the original fragments-the PA1486 (No.7/XJY 6a) occipital bone, PA1490 (No.10/XJY 6b) right parietal bone, and PA1498 (No.17/XJY 15) left temporal bone-which originated from the same young adult individual. The XJY 6 endocranial capacity, estimated by measuring endocranial volume, was estimated using multiple regression formulae derived from ectocranial and endocranial measurements on select samples of Pleistocene hominins and recent modern humans. The results indicate that the larger pooled sample of both Pleistocene and recent modern humans was more robust for the endocranial capacity estimate. Based on the pooled sample using the ectocranial and endocranial measurements, we conservatively estimate the XJY 6 endocranial volume to be ∼1700 cm3 with a 95% confidence interval of 1555-1781 cm3. This is close to Xuchang 1, which dates to 125-105 ka and whose endocranial volume is ∼1800 cm3. Thus, XJY 6 provides the earliest evidence of a brain size that falls in the upper range of Neanderthals and modern Homo sapiens. XJY 6, together with Xuchang 1, Homo floresiensis, Homo luzonensis, and Homo naledi, challenge the general pattern that brain size gradually increases over geological time. This study also finds that hominin brain size expansion occurred at different rates across time and space.


Assuntos
Hominidae , Homem de Neandertal , Animais , Evolução Biológica , China , Fósseis , Hominidae/anatomia & histologia , Humanos , Homem de Neandertal/anatomia & histologia , Crânio/anatomia & histologia , Osso Temporal/anatomia & histologia
3.
Am J Biol Anthropol ; 177(3): 471-488, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-36787692

RESUMO

OBJECTIVES: As hands and feet are serially repeated corresponding structures in tetrapods, the morphology of fingers and toes is expected to covary due to a shared developmental origin. The present study focuses on the covariation of the shape of proximal finger and toe phalanges of adult Homo sapiens to determine whether covariation is different in the first ray relative to the others, as its morphology is also different. MATERIAL AND METHODS: Proximal phalanges of 76 individuals of unknown sex (Muséum national d'Histoire naturelle, Paris, and the Natural History Museum, London) were digitized using a surface scanner. Landmarks were positioned on 3D surface models of the phalanges. Generalized Procrustes analysis and two-block partial least squares (PLS) analyses were conducted. A novel landmark-based geometric morphometric approach focusing on covariation is based on a PCoA of the angles between PLS axes in morphospace. The results can be statistically evaluated. RESULTS: The difference in PCo scores between the first and the other rays indicates that the integration between the thumb and the big toe is different from that between the lateral rays of the hand and foot. DISCUSSION: We speculate that the results are possibly the evolutionary consequence of differential selection pressure on the big toe relative to the other toes related to the rise of bipedalism, which is proposed to have emerged very early in the hominin clade. In contrast, thumb morphology and its precision grip never ceased undergoing changes, suggesting less acute selection pressures related to the evolution of the precision grip.


Assuntos
Falanges dos Dedos da Mão , Hominidae , Adulto , Animais , Humanos , Falanges dos Dedos do Pé/diagnóstico por imagem , Mãos , Falanges dos Dedos da Mão/diagnóstico por imagem , Polegar
4.
J Anthropol Sci ; 99: 19-60, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34894396

RESUMO

In two publications from 1967 and 1971, M. Masali described human skeletal remains presumed to have been found in the Balzi Rossi caves (Ventimiglia, Italy), based on a signed note dated to 1908. Since then, the remains - dubbed "Conio's Finds" and preserved at the University of Torino - had not been further studied. We performed a multidisciplinary investigation aimed at clarifying the geographical and chronological attribution of these specimens. Collagen extraction for AMS dating was unsuccessful, but we obtained two direct dates on the best- preserved crania via 231Pa/235U direct gamma-ray spectrometry (10,500±2,000 years BP and 12,500±2,500 years BP). We analyzed the metrics and morphology of the crania and femora by comparing them with samples belonging to the Upper Paleolithic, Mesolithic, and Neolithic periods, and evidenced that the "Conio's Finds" are morphologically more compatible with a Late Pleistocene rather than Holocene attribution. We analyzed the literature regarding the history of excavations at Balzi Rossi, and we propose that - if any credence should be given to the note accompanying the material - the remains may have been found in front of Grotta dei Fanciulli or Grotta del Caviglione, in the redeposited soil dug up during the installation of lime kilns carried out between the late 18th and the early 19th centuries. These hypotheses may be tested in the future by comparing the speleothem deposited on one of the crania and the remaining deposit at the site.

5.
PLoS One ; 15(1): e0227362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978063

RESUMO

The cranium is an anatomically complex structure. One source of its complexity is due to its modular organization. Cranial modules are distinct and partially independent units that interact substantially during ontogeny thus generating morphological integration. Artificial Cranial Deformation (ACD) occurs when the human skull is intentionally deformed, through the use of different deforming devices applied to the head while it is developing. Hence, ACD provides an interesting example to assess the degree to which biomechanical perturbations of the developing neurocranium impact on the degree of morphological integration in the skull as a whole. The main objective of this study was to assess how ACD affects the morphological integration of the skull. This was accomplished by comparing a sample of non-deformed crania and two sets of deformed crania (i.e. antero-posterior and oblique). Both developmental and static modularity and integration were assessed through Generalized Procrustes Analysis by considering the symmetric and asymmetric components of variation in adults, using 3D landmark coordinates as raw data. The presence of two developmental modules (i.e. viscero and neurocranium) in the skull was tested. Then, in order to understand how ACD affects morphological integration, the covariation pattern between the neuro and viscerocranium was examined in antero-posterior, oblique and non-deformed cranial categories using Partial Least-Squares. The main objective of this study was to assess how ACD affects the morphological integration of the skull. This was accomplished by comparing a sample of deformed (i.e. antero-posterior and oblique) and non-deformed crania. Hence, differences in integration patterns were compared between groups. The obtained results support the modular organization of the human skull in the two analyzed modules. The integration analyses show that the oblique ACD style differentially affects the static morphological integration of the skull by increasing the covariance between neuro and viscerocranium in a more constrained way than in antero-posterior and non-deformed skulls. In addition, the antero-posterior ACD style seems to affect the developmental integration of the skull by directing the covariation pattern in a more defined manner as compared to the other cranial categories.


Assuntos
Ossos Faciais/anatomia & histologia , Base do Crânio/anatomia & histologia , Arqueologia , Evolução Biológica , Chile , Humanos
6.
J Anthropol Sci ; 96: 151-172, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31909734

RESUMO

Scenarios for the dispersal of Homo sapiens in Southern Europe and in the Mediterranean basin have been uncertain, given the scarceness of osteological samples and the simplicity of the proposed archaeologically-based settlement hypotheses. According to available data, the first anatomically modern humans entered Sicily during the Late Pleistocene, coming from the Italian peninsula. A presumably small Late Epigravettian population colonised coastal sites. Later, North-Western archaeological horizons gave hospitality to a significant Mesolithic expansion. In order to verify a hypothesis of continuity in the peopling of the island, we analyzed Sicilian skulls from the Late Epigravettian site of San Teodoro, Eastern Sicily (AMS 14C dated at 14,500 BP) and from the Mesolithic period (14C dated from 9,500 to 8,500 BP) coming from various sites (Uzzo, Molara, Grotta d'Oriente) located on the North Western coast of the island. The aims were to test the biological variability through time within the island as well as to evaluate the relationships of Sicilian Pleistocene hunter-gatherers with Old World populations. We also evaluated the Sicilian Mesolithic uniformity especially between the Uzzo and Grotta d'Oriente sites, given their vicinity and accessibility during the Early Holocene. We applied 3D geometric morphometric methods to assess shape variation as well as geographic and diachronic morphological patterns. All analyzed specimens, plus a comparative sample from the Old World dated from the Upper Paleolithic to recent periods, were transformed in digital images and standard craniofacial landmarks were extracted from the 3D models. Our results underline a high variability among the Mesolithic specimens, as well as a large craniometric distance from the presumed founder Paleolithic settler representatives (San Teodoro specimens) that have closer morphological affinities with other European Upper Paleolithic specimens.


Assuntos
Crânio/anatomia & histologia , Adulto , Antropologia Física , Evolução Biológica , Cefalometria , Feminino , Fósseis , História Antiga , Migração Humana/história , Humanos , Masculino , Filogenia , Sicília
7.
J Anat ; 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29926913

RESUMO

Intentional cranial deformations are the result of external mechanical forces exerted on the skull vault that modify the morphology of various craniofacial structures such as the skull base, the orbits and the zygoma. In this controlled study, we investigated the 3D shape of the orbital inner mould and the orbital volume in various types of intentional deformations and in adult non-operated scaphocephaly - the most common type of craniosynostosis - using dedicated morphometric methods. CT scans were performed on 32 adult skulls with intentional deformations, 21 adult skull with scaphocephaly and 17 non-deformed adult skulls from the collections of the Muséum national d'Histoire naturelle in Paris, France. The intentional deformations group included six skulls with Toulouse deformations, eight skulls with circumferential deformations and 18 skulls with antero-posterior deformations. Mean shape models were generated based on a semi-automatic segmentation technique. Orbits were then aligned and compared qualitatively and quantitatively using colour-coded distance maps and by computing the mean absolute distance, the Hausdorff distance, and the Dice similarity coefficient. Orbital symmetry was assessed after mirroring, superimposition and Dice similarity coefficient computation. We showed that orbital shapes were significantly and symmetrically modified in intentional deformations and scaphocephaly compared with non-deformed control skulls. Antero-posterior and circumferential deformations demonstrated a similar and severe orbital deformation pattern resulting in significant smaller orbital volumes. Scaphocephaly and Toulouse deformations had similar deformation patterns but had no effect on orbital volumes. This study showed that intentional deformations and scaphocephaly significantly interact with orbital growth. Our approach was nevertheless not sufficient to identify specific modifications caused by the different types of skull deformations or by scaphocephaly.

8.
Am J Hum Biol ; 28(5): 646-61, 2016 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-26924543

RESUMO

OBJECTIVES: Craniofacial variation in past and present Amerindians has been attributed to the effect of multiple founder events, or to one major migration followed by in situ differentiation and possibly recurrent contacts among Circum-Arctic groups. Our study aims to: (i) detect morphological differences that may indicate several migrations; (ii) test for the presence of genetic isolation; and (iii) test the correlation between shape data and competing settlement hypotheses by taking into account geography, chronology, climate effects, the presence of genetic isolation and recurrent gene flow. METHODS: We analyzed a large sample of three-dimensional (3D) cranial surface scans (803 specimens) including past and modern groups from America and Australasia. Shape variation was investigated using geometric morphometrics. Differential external gene flow was evaluated by applying genetic concepts to morphometric data (Relethford-Blangero approach). Settlement hypotheses were tested using a matrix correlation approach (Mantel tests). RESULTS: Our results highlight the strong dichotomy between Circum-Arctic and continental Amerindians as well as the impact of climate adaptation, and possibly recurrent gene flow in the Circum-Arctic area. There is also evidence for the impact of genetic isolation on phenetic variation in Baja California. Several settlement hypotheses are correlated with our data. CONCLUSIONS: The three approaches used in this study highlight the importance of local processes especially in Baja California, and caution against the use of overly simplistic models when searching for the number of migration events. The results stress the complexity of the settlement of the Americas as well as the mosaic nature of the processes involved in this process. Am. J. Hum. Biol. 28:646-661, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Migração Humana , Crânio/anatomia & histologia , Indígena Americano ou Nativo do Alasca , América , Antropologia Física , Feminino , Fluxo Gênico , Humanos , Masculino
9.
Am J Phys Anthropol ; 154(1): 152-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24711122

RESUMO

This study assessed three-dimensional (3D) photogrammetry as a tool for capturing and quantifying human skull morphology. While virtual reconstruction with 3D surface scanning technology has become an accepted part of the paleoanthropologist's tool kit, recent advances in 3D photogrammetry make it a potential alternative to dedicated surface scanners. The principal advantages of photogrammetry are more rapid raw data collection, simplicity and portability of setup, and reduced equipment costs. We tested the precision and repeatability of 3D photogrammetry by comparing digital models of human crania reconstructed from conventional, 2D digital photographs to those generated using a 3D surface scanner. Overall, the photogrammetry and scanner meshes showed low degrees of deviation from one another. Surface area estimates derived from photogrammetry models tended to be slightly larger. Landmark configurations generally did not cluster together based upon whether the reconstruction was created with photogrammetry or surface scanning technology. Average deviations of landmark coordinates recorded on photogrammetry models were within the generally allowable range of error in osteometry. Thus, while dependent upon the needs of the particular research project, 3D photogrammetry appears to be a suitable, lower-cost alternative to 3D imaging and scanning options.


Assuntos
Cefalometria/métodos , Imageamento Tridimensional/métodos , Fotogrametria/métodos , Crânio/anatomia & histologia , Antropologia Física , Humanos
10.
J Forensic Sci ; 58(6): 1420-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24020394

RESUMO

In the past, improvements in craniofacial reconstructions (CFR) methodology languished due to the lack of adequate 3D databases that were sufficiently large and appropriate for 3-dimensional shape statistics. In our study, we created the "FACE-R" database from CT records and 3D surface scans of 400 clinical patients from Hungary, providing a significantly larger sample that was available before. The uniqueness of our database is linking of two data types that makes possible to investigate the bone and skin surface of the same individual, in upright position, thus eliminating many of the gravitational effects on the face during CT scanning. We performed a preliminary geometric morphometric (GMM) study using 3D data that produces a general idea of skull and face shape correlations. The vertical position of the tip of the (soft) nose for a skull and landmarks such as rhinion need to be taken into account. Likewise, the anterior nasal spine appears to exert some influence in this regard.


Assuntos
Bases de Dados Factuais , Face/diagnóstico por imagem , Ossos Faciais/diagnóstico por imagem , Imageamento Tridimensional , Tomografia Computadorizada Multidetectores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Antropologia Forense , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise de Regressão , Software , Adulto Jovem
11.
J Anthropol Sci ; 90: 7-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22781581

RESUMO

As virtual anthropology is becoming more and more ubiquitous, so are the means to acquire, process and analyze 3D data. Among these means, surface scanners have gained a prominent place for a variety of reasons that make them useful to anthropologists. While surface scanning has several advantages over other 3D devices (digitizers, volume scanners etc.), it does come with one obvious drawback - internal structures remain invisible. Still, surface scanning is emerging as a convenient tool for anthropometric and especially paleoanthropological research. It extends our ability to quantify phenotypic variation, its non-destructive nature contributes to specimen conservation, and it can become an integral part of virtual anthropology, thus doing more than just "scratching the surface".


Assuntos
Antropologia Física/métodos , Diagnóstico por Imagem/métodos , Imageamento Tridimensional/métodos , Humanos , Processamento de Imagem Assistida por Computador , Paleontologia , Propriedades de Superfície
12.
Ergonomics ; 52(9): 1128-43, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19606363

RESUMO

Updated harness designs are needed to accommodate diverse populations in the current workforce. This paper determined an improved fall-arrest harness sizing scheme and strap-length configurations for harness design. A 3-D elliptic Fourier analysis (EFA) procedure with 123 coefficients was developed to quantify torso-shape effect on harness fit, based on 3-D data of 108 women and 108 men. The EFA coefficients were then applied to 600 representative body scans from a national database of 2382 participants to establish an improved sizing system. Study outcomes suggested a more upward back D-ring location for women than current unisex designs to accommodate female torso form and mitigate their fit problem. Results also suggested an improved system of three sizes for women and three sizes for men. New harness sizing charts for women and men were proposed accordingly. Using the most current 3-D whole-body digital scanning technology, this study assembled data from a US workforce to establish an improved fall-arrest harness sizing system and strap configurations for men and women. The information is useful for new generation harness designs to reduce the risk of worker injury.


Assuntos
Acidentes por Quedas/prevenção & controle , Acidentes de Trabalho/prevenção & controle , Equipamentos de Proteção , Antropometria , Estatura , Peso Corporal , Desenho de Equipamento , Feminino , Humanos , Masculino , Equipamentos de Proteção/normas , Fatores Sexuais , Tórax/anatomia & histologia
14.
Am J Phys Anthropol ; 122(1): 11-22, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12923900

RESUMO

The anatomical effects of artificial cranial deformation on the face and the base have been subject to various metric approaches, including standard linear as well as finite element techniques, and have produced controversial results (Antón [1989] Am. J. Phys. Anthropol. 79:253-267; Kohn et al. [1993] Am. J. Phys. Anthropol. 90:147-158). It can be argued that diverging observations partly result from methodological constraints. The present study compares samples of intentionally deformed and undeformed human crania, using elliptic Fourier analysis (EFA), a morphometric approach which has been shown to be particularly appropriate for characterizing the shape of two-dimensional outlines and associated shape changes. We improve the standard EFA approach by adding a preliminary orientation of the outlines following the rotation parameters of a Procrustes superimposition, using multiple homologous landmarks called control points. The results confirm that circumferentially deformed skulls exhibit modifications of the basioccipital region, together with increased anterior and inferior facial projection. However, the degree to which basioccipital flattening is modified in circumferentially deformed Peruvians was found to be less marked than changes observed in the face. Some of the modifications observed here can be related to morphological trends existing in the population from which our sample was taken. The observation of other modifications may be subject to methodological constraints of standard morphometric approaches.


Assuntos
Indígena Americano ou Nativo do Alasca , Antropologia Física/métodos , Povo Asiático , Crânio/anormalidades , Crânio/anatomia & histologia , Adulto , Feminino , Análise de Fourier , Humanos , Masculino , Valores de Referência
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