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Schmid T, Dritsas K, Gebistorf M, Halazonetis D, Katsaros C, Gkantidis N. Long-term occlusal tooth wear at the onset of permanent dentition. Clin Oral Investig 2024; 28:155. [PMID: 38366215 PMCID: PMC10873235 DOI: 10.1007/s00784-024-05550-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 02/07/2024] [Indexed: 02/18/2024]
Abstract
OBJECTIVES This study quantified the long-term occlusal wear in the natural posterior teeth and the associations per tooth type within the dentition. METHODS The sample included 70 orthodontically treated subjects (52 females and 18 males; median age, 14.3 years), followed for a 12.7-year period. They were consecutively selected with no tooth wear-related criteria. Post-treatment (T1) and follow-up dental casts (T2) were scanned and superimposed through three-dimensional methods. Occlusal wear volume of posterior teeth and tooth wear patterns were investigated through non-parametric statistics and analysis of covariance. RESULTS There were no significant differences between contralateral teeth. The average occlusal wear per posterior tooth was 2.3 mm3, with 65.2% of teeth showing values greater than 1 mm3. Males, mandibular teeth, and first molars exhibited slightly greater wear levels than females (median, 2.57 and 2.21 mm3, respectively; p = 0.005), maxillary teeth, and first or second premolars, respectively. In all first premolars and in the mandibular second premolars, the buccal cusps were primarily affected with no other distinct patterns. There were weak to moderate correlations between tooth types, apart from certain strong correlations detected in males. CONCLUSIONS Posterior tooth wear was highly prevalent after a 13-year period starting at the onset of permanent dentition. The detected patterns are in accordance with the concept of canine guidance occlusion that is transforming into group synergy through function. CLINICAL RELEVANCE The widespread tooth wear occurrence and the high intra- and inter-individual variability underline the need for individual patient monitoring to identify high-risk patients at early stages.
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Affiliation(s)
- Thomas Schmid
- Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010, Bern, Switzerland
| | - Konstantinos Dritsas
- Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010, Bern, Switzerland
| | - Meret Gebistorf
- Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010, Bern, Switzerland
| | - Demetrios Halazonetis
- Department of Orthodontics, School of Dentistry, National and Kapodistrian University of Athens, 11527, Athens, Greece
| | - Christos Katsaros
- Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010, Bern, Switzerland
| | - Nikolaos Gkantidis
- Department of Orthodontics and Dentofacial Orthopedics, School of Dental Medicine, University of Bern, Freiburgstrasse 7, CH-3010, Bern, Switzerland.
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Scerri EML, Will M. The revolution that still isn't: The origins of behavioral complexity in Homo sapiens. J Hum Evol 2023; 179:103358. [PMID: 37058868 DOI: 10.1016/j.jhevol.2023.103358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 04/16/2023]
Abstract
The behavioral origins of Homo sapiens can be traced back to the first material culture produced by our species in Africa, the Middle Stone Age (MSA). Beyond this broad consensus, the origins, patterns, and causes of behavioral complexity in modern humans remain debated. Here, we consider whether recent findings continue to support popular scenarios of: (1) a modern human 'package,' (2) a gradual and 'pan-African' emergence of behavioral complexity, and (3) a direct connection to changes in the human brain. Our geographically structured review shows that decades of scientific research have continuously failed to find a discrete threshold for a complete 'modernity package' and that the concept is theoretically obsolete. Instead of a continent-wide, gradual accumulation of complex material culture, the record exhibits a predominantly asynchronous presence and duration of many innovations across different regions of Africa. The emerging pattern of behavioral complexity from the MSA conforms to an intricate mosaic characterized by spatially discrete, temporally variable, and historically contingent trajectories. This archaeological record bears no direct relation to a simplistic shift in the human brain but rather reflects similar cognitive capacities that are variably manifested. The interaction of multiple causal factors constitutes the most parsimonious explanation driving the variable expression of complex behaviors, with demographic processes such as population structure, size, and connectivity playing a key role. While much emphasis has been given to innovation and variability in the MSA record, long periods of stasis and a lack of cumulative developments argue further against a strictly gradualistic nature in the record. Instead, we are confronted with humanity's deep, variegated roots in Africa, and a dynamic metapopulation that took many millennia to reach the critical mass capable of producing the ratchet effect commonly used to define contemporary human culture. Finally, we note a weakening link between 'modern' human biology and behavior from around 300 ka ago.
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Affiliation(s)
- Eleanor M L Scerri
- Pan-African Evolution Research Group, Max Planck Institute for Geoanthropology, Kahlaische Str. 10, 07749, Jena, Germany; Department of Classics and Archaeology, University of Malta, Msida, MSD 2080, Malta; Department of Prehistory, University of Cologne, 50931, Cologne, Germany.
| | - Manuel Will
- Department of Early Prehistory and Quaternary Ecology, University of Tübingen, Schloss Hohentübingen, Burgsteige 11, 72070, Tübingen, Germany
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Wang Y, Zhang X, Sun X, Yi S, Min K, Liu D, Yan W, Cai H, Wang X, Curnoe D, Lu H. A new chronological framework for Chuandong Cave and its implications for the appearance of modern humans in southern China. J Hum Evol 2023; 178:103344. [PMID: 36947893 DOI: 10.1016/j.jhevol.2023.103344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 03/24/2023]
Abstract
Chuandong Cave is an important Late Paleolithic site because it documents the early appearance of bone tools in southern China. We used the single-aliquot regenerative-dose protocol for optically stimulated luminescence dating to improve the precision of the chronology for the Chuandong Cave sedimentary sequence. The age of each layer was determined using a Bayesian modeling approach which combined optically stimulated luminescence ages with published AMS 14C dates. The results showed that Layer 10 began accumulating since 56 ± 14 ka and provides the upper age limit for all artifacts from the sequence. Bone awl tools from Layer 8, the earliest grinding bone tools in this site, were recovered within sediments between 40 ± 7 ka and 30 ± 4 ka. Layer 8 also indicates the appearance of modern humans in the Chuandong Cave sequence. Layers 4-2, ranging from 15 ± 3 ka until 11 ± 1 ka and including the Younger Dryas period, contain a few bone awls and an eyed bone needle. The shift from bone awls to eyed bone needles in the Chuandong Cave sequence indicates that modern humans adapted to the changing climate of southern China. We conclude that modern human behavior in bone tools appeared in southern China as early as 40 ± 7 ka, became more sophisticated during the Last Glacial Maximum, and spread more widely across southern China during the Younger Dryas.
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Affiliation(s)
- Yanan Wang
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Xinglong Zhang
- Guizhou Provincial Institute of Cultural Relics and Archaeology, Guiyang 550003, China
| | - Xuefeng Sun
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China.
| | - Shuangwen Yi
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Kai Min
- Guizhou Provincial Institute of Cultural Relics and Archaeology, Guiyang 550003, China
| | - Dengke Liu
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Wenxuan Yan
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Huiyang Cai
- Guizhou Provincial Museum, Guiyang 550081, China
| | - Xinjin Wang
- Guizhou Provincial Institute of Cultural Relics and Archaeology, Guiyang 550003, China
| | - Darren Curnoe
- Australia Museum Research Institute, 1 William Street, Darlinghurst, NSW 2010, Australia
| | - Huayu Lu
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
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Zubova AV, Moiseyev VG, Kulkov AM, Otcherednoy AK, Markin SV, Kolobova KA. Maxillary second molar from the Rozhok I Micoquian site (Azov Sea region): Another link between Eastern Europe and Siberia. J Hum Evol 2022; 168:103209. [PMID: 35617848 DOI: 10.1016/j.jhevol.2022.103209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Alisa V Zubova
- Peter the Great Museum of Anthropology and Ethnography (Kunstkamera), Russian Academy of Sciences, Universitetskaya emb. 3, St. Petersburg, 199034, Russia; Institute of Archaeology and Ethnography, Siberian Branch of the Russian Academy of Sciences, Lavrentieva av., 17, Novosibirsk, 630090, Russia.
| | - Vyacheslav G Moiseyev
- Peter the Great Museum of Anthropology and Ethnography (Kunstkamera), Russian Academy of Sciences, Universitetskaya emb. 3, St. Petersburg, 199034, Russia
| | - Alexander M Kulkov
- Saint Petersburg State University, Universitetskaya emb. 7-9, St. Petersburg, 199034, Russia
| | - Aleksander K Otcherednoy
- Institute for the History of Material Culture, Russian Academy of Sciences, Dvortsovaya emb. 18, St. Petersburg, 191186, Russia
| | - Sergey V Markin
- Institute of Archaeology and Ethnography, Siberian Branch of the Russian Academy of Sciences, Lavrentieva av., 17, Novosibirsk, 630090, Russia
| | - Ksenia A Kolobova
- Institute of Archaeology and Ethnography, Siberian Branch of the Russian Academy of Sciences, Lavrentieva av., 17, Novosibirsk, 630090, Russia
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Wei P, Weng Z, Carlson KJ, Cao B, Jin L, Liu W. Late Pleistocene partial femora from Maomaodong, southwestern China. J Hum Evol 2021; 155:102977. [PMID: 33895609 DOI: 10.1016/j.jhevol.2021.102977] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 02/15/2021] [Accepted: 02/15/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Pianpian Wei
- Ministry of Education Key Laboratory of Contemporary Anthropology, Department of Anthropology and Human Genetics, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Zekun Weng
- Guizhou Municipal Institute of Cultural Relics and Archaeology, Guiyang, 5500044, China.
| | - Kristian J Carlson
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA; Evolutionary Studies Institute, University of the Witwatersrand, WITS 2050, Johannesburg, South Africa.
| | - Bo Cao
- Guizhou Municipal Institute of Cultural Relics and Archaeology, Guiyang, 5500044, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China; Human Phoneme Institute, Fudan University, Shanghai, 200438, China
| | - Wu Liu
- Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Palaeontology and Palaeoanthropology, Chinese Academy of Sciences, Beijing 100044, China; CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
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Barzilai O, Marder O, Hershkovitz I. In search of modern humans and the Early Upper Paleolithic at Manot Cave: An introduction. J Hum Evol 2021; 160:102965. [PMID: 33714606 DOI: 10.1016/j.jhevol.2021.102965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 01/30/2021] [Accepted: 01/30/2021] [Indexed: 10/21/2022]
Abstract
Manot Cave is a unique relict karst cave located in the western Galilee, north-western Israel. The cave was inhabited from the Late Middle Paleolithic through the Early Upper Paleolithic (EUP) periods until its main entrance collapsed, ca. 30 ka. The cave consists of an elongated main hall and two side chambers. The topography of the main hall consists of a steep talus inclining from the original entrance of the cave to the center, a plane area at the lowermost point of the main hall, and a smaller talus inclining from the eastern end of the cave. Nine field seasons (2010-2018) have been conducted so far at the cave. The excavations revealed dense accumulations of EUP deposits near the cave entrance (areas E and I), at the center (area D), at the base of the western talus (area C), and in the plane area (area A). This introductory article describes the cave and its characteristics and provides a background for various contributions in the special issue, devoted to Manot Cave.
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Affiliation(s)
- Omry Barzilai
- Archaeological Research Department, Israel Antiquities Authority, POB 586, Jerusalem 91004, Israel.
| | - Ofer Marder
- Department of Bible, Archaeology and the Ancient Near East, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 8410501, Israel
| | - Israel Hershkovitz
- Department of Anatomy and Anthropology, Dan David Center for Human Evolution and Biohistory Research, Shmunis Family Anthropology Institute, Sackler Faculty of Medicine, Tel Aviv University, POB 39040, Tel Aviv 6997801, Israel
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Abstract
BACKGROUND Recent paleogenomic studies have highlighted a very small set of proteins carrying modern human-specific missense changes in comparison to our closest extinct relatives. Despite being frequently alluded to as highly relevant, species-specific differences in regulatory regions remain understudied. Here, we integrate data from paleogenomics, chromatin modification and physical interaction, and single-cell gene expression of neural progenitor cells to identify derived regulatory changes in the modern human lineage in comparison to Neanderthals/Denisovans. We report a set of genes whose enhancers and/or promoters harbor modern human single nucleotide changes and are active at early stages of cortical development. RESULTS We identified 212 genes controlled by regulatory regions harboring modern human changes where Neanderthals/Denisovans carry the ancestral allele. These regulatory regions significantly overlap with putative modern human positively-selected regions and schizophrenia-related genetic loci. Among the 212 genes, we identified a substantial proportion of genes related to transcriptional regulation and, specifically, an enrichment for the SETD1A histone methyltransferase complex, known to regulate WNT signaling for the generation and proliferation of intermediate progenitor cells. CONCLUSIONS This study complements previous research focused on protein-coding changes distinguishing our species from Neanderthals/Denisovans and highlights chromatin regulation as a functional category so far overlooked in modern human evolution studies. We present a set of candidates that will help to illuminate the investigation of modern human-specific ontogenetic trajectories.
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Affiliation(s)
- Juan Moriano
- Universitat de Barcelona, Gran Via de les Corts Catalanes, Barcelona, Spain.
- Universitat de Barcelona Institute of Complex Systems, Martı́ Franquès, Barcelona, Spain.
| | - Cedric Boeckx
- Universitat de Barcelona, Gran Via de les Corts Catalanes, Barcelona, Spain.
- Universitat de Barcelona Institute of Complex Systems, Martı́ Franquès, Barcelona, Spain.
- Catalan Institution for Research and Advanced Studies, Passeig Lluı́s Companys, Barcelona, Spain.
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Weissbrod L, Weinstein-Evron M. Climate variability in early expansions of Homo sapiens in light of the new record of micromammals in Misliya Cave, Israel. J Hum Evol 2020; 139:102741. [PMID: 32062432 DOI: 10.1016/j.jhevol.2020.102741] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 12/27/2019] [Accepted: 12/27/2019] [Indexed: 11/23/2022]
Abstract
In this study, we provide the first taphonomic and taxonomic descriptions of the micromammals from Misliya Cave, where recently a Homo sapiens hemimaxilla has been reported. This finding significantly extends the time frame for the out-of-Africa presence of anatomically modern humans. It also provides an opportunity to reassess variation in early modern human population responses to climate change in the Levantine sequence. Information on species ranking and diversity estimations (Shannon functions) is obtained from quantitative data across 31 Levantine assemblages and investigated in a broad comparative frame using multivariate analyses. Recent models of human-climate interactions in the late Early-Middle Paleolithic of the southern Levant have drawn heavily on on-site associations of human fossils with remains of micromammals. However, there has been little, if any, attempt to examine the long-term picture of how paleocommunities of micromammals responded qualitatively and quantitatively to climatic oscillations of the region by altering their compositional complexity. Consequently, our understanding is vastly limited in regard to the paleoecosystem functions that linked past precipitation shifts to changes in primary producers and consumers or as to the background climatic conditions that allowed for the development of highly nonanalog ancient communities in the region. Although previous studies argued for a correspondence between alternations in H. sapiens and Neanderthal occupations of the Levant and faunal shifts in key biostratigraphic indicator taxa (such as Euro-Siberian Ellobius versus Saharo-Arabian Mastomys and Arvicanthis), our data indicate the likelihood that early H. sapiens populations (Misliya and Qafzeh hominins) persisted through high amplitudes of paleoecological and climatic oscillations. It is unlikely, given these results, that climate functioned as a significant filter of early modern human persistence and genetic interactions with Neanderthals in the Levant.
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Abstract
BACKGROUND Skin color is a well-recognized adaptive trait and has been studied extensively in humans. Understanding the genetic basis of adaptation of skin color in various populations has many implications in human evolution and medicine. DISCUSSION Impressive progress has been made recently to identify genes associated with skin color variation in a wide range of geographical and temporal populations. In this review, we discuss what is currently known about the genetics of skin color variation. We enumerated several cases of skin color adaptation in global modern humans and archaic hominins, and illustrated why, when, and how skin color adaptation occurred in different populations. Finally, we provided a summary of the candidate loci associated with pigmentation, which could be a valuable reference for further evolutionary and medical studies. CONCLUSION Previous studies generally indicated a complex genetic mechanism underlying the skin color variation, expanding our understanding of the role of population demographic history and natural selection in shaping genetic and phenotypic diversity in humans. Future work is needed to dissect the genetic architecture of skin color adaptation in numerous ethnic minority groups around the world, which remains relatively obscure compared with that of major continental groups, and to unravel the exact genetic basis of skin color adaptation.
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Affiliation(s)
- Lian Deng
- Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, CAS, Shanghai, 200031 China.,University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Shuhua Xu
- Chinese Academy of Sciences (CAS) Key Laboratory of Computational Biology, Max Planck Independent Research Group on Population Genomics, CAS-MPG Partner Institute for Computational Biology (PICB), Shanghai Institutes for Biological Sciences, CAS, Shanghai, 200031 China.,University of Chinese Academy of Sciences, Beijing, 100049 China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210 China.,Collaborative Innovation Center of Genetics and Development, Shanghai, 200438 China
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Langley MC, O'Connor S, Piotto E. 42,000-year-old worked and pigment-stained Nautilus shell from Jerimalai (Timor-Leste): Evidence for an early coastal adaptation in ISEA. J Hum Evol 2016; 97:1-16. [PMID: 27457541 DOI: 10.1016/j.jhevol.2016.04.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 11/28/2022]
Abstract
In this paper, we describe worked and pigment-stained Nautilus shell artefacts recovered from Jerimalai, Timor-Leste. Two of these artefacts come from contexts dating to between 38,000 and 42,000 cal. BP (calibrated years before present), and exhibit manufacturing traces (drilling, pressure flaking, grinding), as well as red colourant staining. Through describing more complete Nautilus shell ornaments from younger levels from this same site (>15,900, 9500, and 5000 cal. BP), we demonstrate that those dating to the initial occupation period of Jerimalai are of anthropogenic origin. The identification of such early shell working examples of pelagic shell in Island Southeast Asia not only adds to our growing understanding of the importance of marine resources to the earliest modern human communities in this region, but also indicates that a remarkably enduring shell working tradition was enacted in this area of the globe. Additionally, these artefacts provide the first material culture evidence that the inhabitants of Jerimalai were not only exploiting coastal resources for their nutritional requirements, but also incorporating these materials into their social technologies, and by extension, their social systems. In other words, we argue that the people of Jerimalai were already practicing a developed coastal adaptation by at least 42,000 cal. BP.
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Affiliation(s)
- Michelle C Langley
- Archaeology & Natural History, School of Culture, History & Language, College of Asia and the Pacific, Australian National University, Australia.
| | - Sue O'Connor
- Archaeology & Natural History, School of Culture, History & Language, College of Asia and the Pacific, Australian National University, Australia.
| | - Elena Piotto
- Archaeology & Natural History, School of Culture, History & Language, College of Asia and the Pacific, Australian National University, Australia.
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Eichel KA, Ackermann RR. Variation in the nasal cavity of baboon hybrids with implications for late Pleistocene hominins. J Hum Evol 2016; 94:134-45. [PMID: 27178465 DOI: 10.1016/j.jhevol.2016.02.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 08/03/2015] [Accepted: 02/22/2016] [Indexed: 01/10/2023]
Abstract
Hybridization is increasingly proving to be an important force shaping human evolution. Comparisons of both ancient and modern genomes have provided support for a complex evolutionary scenario over the past million years, with evidence for multiple incidents of gene exchange. However, to date, genetic evidence is still limited in its ability to pinpoint the precise time and place of ancient admixture. For that we must rely on evidence of admixture from the skeleton. The research presented here builds on previous work on the crania of baboon hybrids, focusing on the nasal cavity of olive baboons, yellow baboons, and first generation (F1) hybrids. The nasal cavity is a particularly important anatomical region for study, given the clear differentiation of this feature in Neanderthals relative to their contemporaries, and therefore it is a feature that will likely differ in a distinctive manner in hybrids of these taxa. Metric data consist of 45 linear, area, and volume measurements taken from CT scans of known-pedigree baboon crania. Results indicate that there is clear evidence for differences among the nasal cavities of the parental taxa and their F1 hybrids, including a greater degree of sexual dimorphism in the hybrids. There is also some evidence for transgressive phenotypes in individual F1 animals. The greatest amount of shape variation occurs in the anterior bony cavity, the choana, and the mid-nasopharynx. Extrapolating our results to the fossil record, we would expect F1 hybrid fossils to have larger nasal cavities, on average, than either parental taxon, with overall nasal cavity shape showing the most profound changes in regions that are distinct between the parental taxa (e.g., anterior nasal cavity). We also expect size and shape differences to be more pronounced in male F1 hybrids than in females. Because of pronounced anterior nasal cavity differences between Neanderthals and their contemporaries, we suggest that this model might be effective for examining the fossil record of late Pleistocene contact.
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