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1.
Sci Data ; 9(1): 396, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35817763

RESUMO

Researchers typically rely on fossils from the Family Bovidae to generate African paleoenvironmental reconstructions due to their strict ecological tendencies. Bovids have dominated the southern African fauna for the past four million years and, therefore, dominate the fossil faunal assemblages, especially isolated teeth. Traditionally, researchers reference modern and fossil comparative collections to identify teeth. However, researchers are limited by the specific type and number of bovids at each institution. B.O.V.I.D. (Bovidae Occlusal Visual IDentification) is a repository of images of the occlusal surface of bovid teeth. The dataset currently includes extant bovids from 7 tribes and 20 species (~3900). B.O.V.I.D. contains two scaled images per specimen: a color and a black and white (binarized) image. The database is a useful reference for identifying bovid teeth. The large sample size also allows one to observe the natural variation that exists in each taxa. The binarized images can be used in statistical shape analyses, such as taxonomic classification. B.O.V.I.D. is a valuable supplement to other methods for taxonomically identifying bovid teeth.


Assuntos
Bovinos , Fósseis , Animais , Bases de Dados Factuais , Paleodontologia , Dente/diagnóstico por imagem
2.
São Paulo; s.n; 20220622. 87 p.
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-1373159

RESUMO

A estimativa de idade à morte de indivíduos arqueológicos é um processo muito importante para a reconstrução do perfil demográfico de populações passadas, no entanto, é alvo de debates e discussões quanto à sua acurácia. A estimativa da idade de um indivíduo pelos dentes é um dos métodos mais confiáveis e simples para remanescentes esqueléticos, já que os dentes são altamente resistentes a impactos mecânicos, químicos, físicos e ao tempo. Os objetivos desta tese foram mapear os métodos de estimativa de idade dental utilizados em contexto arqueológico e estimar a idade de indivíduos de cinco sítios arqueológicos pré-coloniais do Estado de São Paulo: Buracão, Capelinha 1, Moraes, Piaçaguera e Tenório sob curadoria do Museu de Arqueologia e Etnologia da Universidade de São Paulo (MAE-USP). Este volume apresenta um compilado de três capítulos que investigaram 1) os métodos de estimativa de idade aplicados em dentes permanentes em indivíduos arqueológicos através de uma revisão de escopo; 2) estimativa de idade a partir da avaliação da proporção das áreas polpa/dente em caninos de indivíduos de sambaquis brasileiros; 3) estimativa de idade a partir da análise dos estágios de mineralização de terceiros molares de indivíduos de sambaquis brasileiros. O primeiro capítulo (revisão de escopo) foi conduzido e relatado de acordo com as recomendações propostas pelo Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) e com o referencial The Joanna Brigs Institute for Scoping Reviews. Para os dois últimos capítulos (realização de estimativa de idade), os dentes de interesse foram radiografados com o aparelho de raios X portátil de corrente direta Nomad e as imagens foram obtidas, exportadas e analisadas em extensão DICOM (Digital Imaging and Communication in Medicine). Os caninos (n=60) foram avaliados e as áreas mensuradas no software livre ImageJ por duas examinadoras calibradas e foi realizado o teste de reprodutibilidade, para toda a amostra, intra (ICC = 0,888 a 0,99) e inter examinadores (ICC = 0,842 a 0,908). Os terceiros molares (n=18) foram avaliados no software livre Stellar View a partir da análise dos estágios de Demirjian e o teste de confiabilidade intra examinador quanto à classificação dos estágios apresentou concordância quase perfeita (Kappa = 0,94). Com a revisão de escopo, foi possível notar uma predileção, na literatura, por métodos não-destrutivos para a estimativa da idade dental em indivíduos arqueológicos; dentre eles, a análise de características do desenvolvimento e maturação dental, a avaliação do depósito de dentina secundária na câmara pulpar e a análise do desgaste dental. A aplicação da proporção das áreas pulpar/dental obteve idades próximas ou que cruzaram os intervalos etários estimados anteriormente por outros métodos antropológicos pelo MAE-USP. A avaliação dos estágios de desenvolvimento apresentou bons resultados: dos 18 dentes avaliados, 15 tiveram a idade estimada dentro do intervalo etário anteriormente avaliado pelo MAE-USP e apenas três não coincidiram, sendo que dois ficaram poucos anos abaixo das idades estimadas anteriormente e o outro, oito anos. Após a realização do estudo, foi possível concluir que ambas as técnicas podem ser aplicadas em remanescentes arqueológicos.


Assuntos
Paleodontologia , Arqueologia , Determinação da Idade pelos Dentes
3.
PLoS One ; 16(11): e0258974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34748581

RESUMO

The region of western Georgia (Imereti) in the Southern Caucasus has been a major geographic corridor for human migrations during the Middle and Upper Paleolithic. Data of recent research and excavations in this region display its importance as a possible route for the dispersal of anatomically modern humans (AMH) into northern Eurasia. Nevertheless, within the local research context, bone-working and personal ornaments have yet contributed but little to the Upper Palaeolithic (UP) regional sequence's characterization. Here we present an archaeozoological, technological and use-wear study of pendants from two local UP assemblages, originating in the Dzudzuana Cave and Satsurblia Cave. The ornaments were made mostly of perforated teeth, though some specimens were made on bone. Both the manufacturing marks made during preparation and use-wear traces indicate that they were personal ornaments, used as pendants or attached to garments. Detailed comparison between ornament assemblages from northern and southern Caucasus reveal that they are quite similar, supporting the observation of cultural bonds between the two regions, demonstrated previously through lithic techno-typological affinities. Furthermore, our study highlights the importance attributed to red deer (Cervus elaphus) by the UP societies of the Caucasus in sharing aesthetic values and/or a symbolic sphere.


Assuntos
Osso e Ossos , Fósseis , Paleodontologia/tendências , Dente , Animais , Arqueologia/tendências , Cavernas , Cervos , República da Geórgia , Humanos
4.
J Hum Evol ; 158: 103047, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34403991

RESUMO

The use of 'teeth as tools' (non-masticatory or cultural-related dental wear) has largely been employed as a proxy for studying of past human behavior, mainly in permanent dentition from adult individuals. Here we present the analysis of the non-masticatory dental wear modifications on the deciduous dentition assigned to eight Neanderthal and anatomically modern human subadult individuals from Mousterian to Magdalenian technocultural contexts in the Cantabrian region (Northern Spain). Although preliminary, we tentatively suggest that these eight subadults present activity-related dental wear, including cultural striations, chipped enamel, toothpick grooves, and subvertical grooves. We also found evidence of habitual dental hygienic practices in the form of toothpicking on a deciduous premolar. Orientation of the cultural striations indicates similar handedness development as in modern children. Taken together, these dental wear patterns support the participation of young individuals in group activities, making them potential contributors to group welfare. This study potentially adds new evidence to the importance of the use of the mouth in paramasticatory activities or as a third hand throughout the Pleistocene, which can be confirmed with a more specific reference sample.


Assuntos
Fósseis , Homem de Neandertal , Desgaste dos Dentes , Dente Decíduo/anatomia & histologia , Animais , História Antiga , Humanos , Paleodontologia , Espanha
5.
J Hum Evol ; 158: 103046, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34332420

RESUMO

Accentuated lines in dental microstructure are hypothesized to correlate with potentially stressful life history events, but our understanding of when, how and why such accentuated lines form in relation to stressful events is limited. We examined accentuated line formation and life history events in the teeth of three naturally deceased mandrills (Mandrillus sphinx, Cercopithecidae), for whom we had detailed life history information. We determined the ages at formation of accentuated lines in histological tooth sections and used dates of birth and death to calibrate dental histology to calendar time and individual age. We found accentuated lines that matched their mother's resumption of sexual cycles in two individuals, and possibly in the third individual. The subjects also formed lines when their mothers were mate-guarded by males or wounded. Accentuated lines matched the birth of the next sibling in one of two cases. Both females formed accentuated lines when they experienced their own sexual swelling cycles, but lines did not match all sexual swelling cycles. Mate-guarding matched an accentuated line in one case, but not in another. Lines matched all three parturitions in the two females. Changes in alpha male and captures did not consistently coincide with accentuated line formation, but repeated captures were associated with lines. Using simulated data, we show that the observed number of matches between lines and events would be very unlikely under a null hypothesis of random line formation. Our results support the hypothesis that some life history events are physiologically stressful enough to cause accentuated line formation in teeth. They contribute to our understanding of how primate life histories are recorded during dental development and enhance our ability to use teeth to reconstruct life history in the absence of direct observation.


Assuntos
Mandrillus , Dente/anatomia & histologia , Animais , Feminino , Gabão , Masculino , Mandrillus/fisiologia , Paleodontologia , Reprodução
7.
Science ; 372(6546): 1105-1107, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083491

RESUMO

Shark populations have been decimated in recent decades because of overfishing and other anthropogenic stressors; however, the long-term impacts of such changes in marine predator abundance and diversity are poorly constrained. We present evidence for a previously unknown major extinction event in sharks that occurred in the early Miocene, ~19 million years ago. During this interval, sharks virtually disappeared from open-ocean sediments, declining in abundance by >90% and morphological diversity by >70%, an event from which they never recovered. This abrupt extinction occurred independently from any known global climate event and ~2 million to 5 million years before diversifications in the highly migratory, large-bodied predators that dominate pelagic ecosystems today, indicating that the early Miocene was a period of rapid, transformative change for open-ocean ecosystems.


Assuntos
Ecossistema , Extinção Biológica , Tubarões , Animais , Peixes , Fósseis , Sedimentos Geológicos , Oceanos e Mares , Paleodontologia , Dente/anatomia & histologia
8.
PLoS One ; 16(3): e0247969, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33690686

RESUMO

Jinyunpelta sinensis is a basal ankylosaurine dinosaur excavated from the mid Cretaceous Liangtoutang Formation of Jinyun County, Zhejiang Province, China. In the present study, its dental microwear was observed using a confocal laser microscope. Jinyunpelta had steep wear facets that covered most of buccal surfaces of posterior dentary teeth. Observation of dental microwear on the wear facet revealed that scratch orientation varied according to its location within the wear facet: vertically (i.e. apicobasally) oriented scratches were dominant in the upper half of the wear facet, and horizontally (i.e. mesiolaterally) oriented ones were in the bottom of the facet. These findings indicated that Jinyunpelta adopted precise tooth occlusion and biphasal jaw movement (orthal closure and palinal lower jaw movement). The biphasal jaw movement was widely observed among nodosaurids, among ankylosaurids, it was previously only known from the Late Cretaceous North American taxa, and not known among Asian ankylosaurids. The finding of biphasal jaw movement in Jinyunpelta showed sophisticate feeding adaptations emerged among ankylosaurids much earlier (during Albian or Cenomanian) than previously thought (during Campanian). The Evolution of the biphasal jaw mechanism that contemporaneously occurred among two lineages of ankylosaurs, ankylosaurids and nodosaurids, showed high evolutionary plasticity of ankylosaur jaw mechanics.


Assuntos
Dinossauros/anatomia & histologia , Desgaste dos Dentes/patologia , Adaptação Fisiológica , Animais , Evolução Biológica , China , Fósseis/anatomia & histologia , História Antiga , Arcada Osseodentária/anatomia & histologia , Mandíbula/anatomia & histologia , Mastigação/fisiologia , Paleodontologia/métodos , Dente/anatomia & histologia , Desgaste dos Dentes/veterinária
9.
Science ; 371(6535): 1253-1256, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33737486

RESUMO

The ecomorphological diversity of extinct elasmobranchs is incompletely known. Here, we describe Aquilolamna milarcae, a bizarre probable planktivorous shark from early Late Cretaceous open marine deposits in Mexico. Aquilolamna, tentatively assigned to Lamniformes, is characterized by hypertrophied, slender pectoral fins. This previously unknown body plan represents an unexpected evolutionary experimentation with underwater flight among sharks, more than 30 million years before the rise of manta and devil rays (Mobulidae), and shows that winglike pectoral fins have evolved independently in two distantly related clades of filter-feeding elasmobranchs. This newly described group of highly specialized long-winged sharks (Aquilolamnidae) displays an aquilopelagic-like ecomorphotype and may have occupied, in late Mesozoic seas, the ecological niche filled by mobulids and other batoids after the Cretaceous-Paleogene boundary.


Assuntos
Evolução Biológica , Fósseis , Tubarões/anatomia & histologia , Tubarões/fisiologia , Nadadeiras de Animais/anatomia & histologia , Animais , Ecossistema , Elasmobrânquios/anatomia & histologia , Elasmobrânquios/fisiologia , Comportamento Alimentar , México , Oceanos e Mares , Paleodontologia , Plâncton , Tubarões/classificação , Natação , Dente/anatomia & histologia
10.
Am J Phys Anthropol ; 174(4): 832-838, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33522597

RESUMO

OBJECTIVES: Standard methods of recording occlusal dental wear are problematic in that they either do not allow for individual variation of wear or are not designed to allow for comparisons of wear patterns. In this article, we (a) present a novel method for recording and analyzing molar wear, and (b) evaluate this method in light of existing methods. MATERIALS AND METHODS: Eighty-two lower mandibular first molars from two regions (medieval Denmark, prehistoric Ohio Valley) were used to assess the method for replicability (intra and inter observer error) and accuracy (comparison to established methods of recording wear). Wear scores were recorded using the MolWear Android App (Beta) by both authors, and established methods of Smith and Scott by the first author. Intraobserver and interobserver error and comparison of the three methods were compared using Spearman's correlation coefficients. RESULTS: The MolWear method presented high intraobserver (r = 0.985, p < 0.01) and interobserver (r = 0.978, p < 0.01) repeatability. Compared to other methods, the method was strongly correlated with Smith (r = 0.962, p < 0.01) and Smith (r = 0.891, p < 0.01). DISCUSSION: The new MolWear method provides an improved way of measuring occlusal molar wear. This method bridges the gaps between established methods, performing comparatively while capturing more information about the distribution of wear in addition to the extent of wear. This method should be used for research comparing interpopulation or intrapopulation quantity of dental wear. While designed for a bioarchaeological population, this method could extend to any Y5 molar including nonhuman primates and hominins.


Assuntos
Dente Molar/patologia , Paleodontologia/métodos , Atrito Dentário/patologia , Humanos , Fotografação
12.
J Hum Evol ; 152: 102939, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33517134

RESUMO

Thirteen permanent fully erupted teeth were excavated at the Paleolithic site of La Cotte de St Brelade in Jersey in 1910 and 1911. These were all found in the same location, on a ledge behind a hearth in a Mousterian occupation level. They were originally identified as being Neanderthal. A fragment of occipital bone was found in a separate locality in a later season. Recent dating of adjacent sediments gives a probable age of <48 ka. The purpose of this article is to provide an updated description of the morphology of this material and consider its likely taxonomic assignment from comparison with Neanderthal and Homo sapiens samples. One of the original teeth has been lost, and we identify one as nonhominin. At least two adult individuals are represented. Cervix shape and the absence of common Neanderthal traits in several teeth suggest affinities with H. sapiens in both individuals, while crown and root dimensions and root morphology of all the teeth are entirely consistent with a Neanderthal attribution, pointing toward a possible shared Neanderthal and H. sapiens ancestry (the likely date of this material corresponds with the time in which both Neanderthals and H. sapiens were present in Europe). The occipital fragment is stratigraphically more recent and does not exhibit any diagnostic Neanderthal features.


Assuntos
Fósseis/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Dente/anatomia & histologia , Animais , Evolução Biológica , Ilhas Anglo-Normandas , Feminino , Paleodontologia
14.
PLoS One ; 15(12): e0241713, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33264306

RESUMO

The Neanderthal specimen from Lamalunga Cave, near Altamura (Apulia, Italy), was discovered during a speleological survey in 1993. The specimen is one of the most complete fossil hominins in Europe and its state of preservation is exceptional, although it is stuck in calcareous concretions and the bones are mostly covered by calcite depositions. Nevertheless, it is possible to carry out some observations on craniodental features that have not previously been described. In this work, we present an account of the oral cavity, made possible by the use of a videoscope, which allowed us to reach some hidden parts of the mandible and palate. This is the first detailed overview of the teeth and maxillary bones of the Neanderthal skeleton from Altamura. The dentition is almost complete. However, two teeth (upper right P3 and upper left M1) were lost ante mortem and four teeth (lower right I1 and P3 and lower left I1 and I2) were lost most probably post mortem. Dental wear is marked. The erupted M3s and the inversion of the compensating curve of Wilson in the M1s and M2s but not in the M3s suggest that the individual is fully adult, but not old. Although most of the teeth have their roots exposed for several millimeters, the periodontal bone appears to be in good condition overall, except in correspondence of the two ante-mortem tooth losses. X-rays of the anterior teeth show a periapical lesion, probably linked to the advanced dental wear. We also observed a weak expression of taurodontism in the posterior dentition and the presence of a retromolar space, features consistent with an attribution to the Neanderthal hypodigm; this attribution is also supported by aspects of the cranial morphology, the morphometric analysis of the scapula and preliminary mtDNA data. There is also a well-developed palatine torus, to the best of our knowledge a feature not previously described in Neanderthals.


Assuntos
Dentição , Fósseis , Hominidae/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Animais , Cavernas , Humanos , Itália , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Boca/fisiologia , Paleodontologia , Crânio/anatomia & histologia , Dente/anatomia & histologia
15.
PLoS One ; 15(11): e0239526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33147255

RESUMO

During the two World Wars, Bartonella quintana was responsible for trench fever and is now recognised as an agent of re-emerging infection. Many reports have indicated widespread B. quintana exposure since the 1990s. In order to evaluate its prevalence in ancient populations, we used real-time PCR to detect B. quintana DNA in 400 teeth collected from 145 individuals dating from the 1st to 19th centuries in nine archaeological sites, with the presence of negative controls. Fisher's exact test was used to compare the prevalence of B. quintana in civil and military populations. B. quintana DNA was confirmed in a total of 28/145 (19.3%) individuals, comprising 78 citizens and 67 soldiers, 20.1% and 17.9% of which were positive for B. quintana bacteraemia, respectively. This study analysed previous studies on these ancient samples and showed that the presence of B. quintana infection followed the course of time in human history; a total of 14/15 sites from five European countries had a positive prevalence. The positive rate in soldiers was higher than those of civilians, with 20% and 18.8%, respectively, in the 18th and 19th centuries, but the difference in frequency was not significant. These results confirmed the role of dental pulp in diagnosing B. quintana bacteraemia in ancient populations and showed the incidence of B. quintana in both civilians and soldiers.


Assuntos
Bacteriemia/diagnóstico , Bartonella quintana/genética , DNA Bacteriano/genética , Dente/microbiologia , Febre das Trincheiras/diagnóstico , Bacteriemia/microbiologia , Bartonella quintana/fisiologia , DNA Bacteriano/isolamento & purificação , Polpa Dentária/microbiologia , Europa (Continente)/epidemiologia , Fósseis/microbiologia , Humanos , Militares , Paleodontologia/métodos , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Febre das Trincheiras/epidemiologia , Febre das Trincheiras/microbiologia
16.
Proc Natl Acad Sci U S A ; 117(42): 26183-26189, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33020281

RESUMO

Teeth have been studied for decades and continue to reveal information relevant to human evolution. Studies have shown that many traits of the outer enamel surface evolve neutrally and can be used to infer human population structure. However, many of these traits are unavailable in archaeological and fossil individuals due to processes of wear and taphonomy. Enamel-dentine junction (EDJ) morphology, the shape of the junction between the enamel and the dentine within a tooth, captures important information about tooth development and vertebrate evolution and is informative because it is subject to less wear and thus preserves more anatomy in worn or damaged specimens, particularly in mammals with relatively thick enamel like hominids. This study looks at the molar EDJ across a large sample of human populations. We assessed EDJ morphological variation in a sample of late Holocene modern humans (n = 161) from archaeological populations using µ-CT biomedical imaging and geometric morphometric analyses. Global variation in human EDJ morphology was compared to the statistical expectations of neutral evolution and "Out of Africa" dispersal modeling of trait evolution. Significant correlations between phenetic variation and neutral genetic variation indicate that EDJ morphology has evolved neutrally in humans. While EDJ morphology reflects population history, its global distribution does not follow expectations of the Out of Africa dispersal model. This study increases our knowledge of human dental variation and contributes to our understanding of dental development more broadly, with important applications to the investigation of population history and human genetic structure.


Assuntos
Evolução Biológica , Esmalte Dentário/anatomia & histologia , Dentina/anatomia & histologia , Fósseis , Paleodontologia , África , América , Ásia , Austrália , Europa (Continente) , Humanos
17.
J Hum Evol ; 147: 102867, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32889336

RESUMO

The site of Riparo Broion (Vicenza, northeastern Italy) preserves a stratigraphic sequence documenting the Middle-to-Upper Paleolithic transition, in particular the final Mousterian and the Uluzzian cultures. In 2018, a human tooth was retrieved from a late Mousterian level, representing the first human remain ever found from this rock shelter (Riparo Broion 1). Here, we provide the morphological description and taxonomic assessment of Riparo Broion 1 with the support of classic and virtual morphology, 2D and 3D analysis of the topography of enamel thickness, and DNA analysis. The tooth is an exfoliated right upper deciduous canine, and its general morphology and enamel thickness distribution support attribution to a Neanderthal child. Correspondingly, the mitochondrial DNA sequence from Riparo Broion 1 falls within the known genetic variation of Late Pleistocene Neanderthals, in accordance with newly obtained radiocarbon dates that point to approximately 48 ka cal BP as the most likely minimum age for this specimen. The present work describes novel and direct evidence of the late Neanderthal occupation in northern Italy that preceded the marked cultural and technological shift documented by the Uluzzian layers in the archaeological sequence at Riparo Broion. Here, we provide a new full morphological, morphometric, and taxonomic analysis of Riparo Broion 1, in addition to generating the wider reference sample of Neanderthal and modern human upper deciduous canines. This research contributes to increasing the sample of fossil remains from Italy, as well as the number of currently available upper deciduous canines, which are presently poorly documented in the scientific literature.


Assuntos
Dente Canino/anatomia & histologia , Fósseis/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Dente Decíduo/anatomia & histologia , Animais , Itália , Maxila , Paleodontologia
18.
J Hum Evol ; 145: 102816, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32580080

RESUMO

The Carabelli trait is a dental feature that forms along the lingual margin of the protocone of deciduous and permanent maxillary molars. It is variably expressed, ranging from a small pit or furrow to a large cusp, and its development seems to be associated with crown size and molar cusp spatial configuration. The degree of expression of the Carabelli trait differs systematically between hominin taxa, and for this reason, it has been used extensively in the reconstruction of their phylogeny. However, the functional implications of having a large Carabelli trait remain unclear. In this study, we analyze the macrowear pattern of maxillary molars of early and late hominins using the occlusal fingerprint analysis method, an approach based on digital models of teeth that helps in reconstructing occlusal dynamics occurring during mastication. Tooth crowns with a small Carabelli cusp generally exhibit larger wear contact areas that extended cervically, while two additional new occlusal contact areas are common in teeth characterized by a large Carabelli cusp. These wear areas are created at the beginning of the chewing cycle, when occluding with the slopes of the lingual groove of the lower molars, between the metaconid and entoconid cusps. Advancing tooth wear leads to a slight enlargement of Carabelli occlusal contacts increasing their functional area. A steep inclination could be mechanically important in food reduction and in balancing the functional load distribution during mastication contacts. Steep wear areas are particularly developed in primates that process foods characterized by tough and fibrous textural properties. Future biomechanical and microwear texture analyses could provide additional information on the mechanical adaptation of this dental trait.


Assuntos
Hominidae/anatomia & histologia , Dente Molar/anatomia & histologia , Anormalidades Dentárias , Coroa do Dente/anatomia & histologia , Desgaste dos Dentes , Animais , Dieta , Mastigação/fisiologia , Maxila/anatomia & histologia , Paleodontologia , Filogenia
19.
Am J Phys Anthropol ; 172(3): 376-385, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32112570

RESUMO

OBJECTIVES: Differences in dental caries prevalence between males and females is considered a reflection of diet. However, recent syntheses argue that sex-specific variation in dental caries prevalence also reflects changes in the oral cavity attributable to variation in reproductive life histories. This study explores sex-specific variation in carious lesions using a life history perspective to understand if differences in reproductive ecology influence this process. MATERIALS AND METHODS: Survival probability between 860 males and females from the Terry Collection was compared using carious lesion manifestation (absent, crown presence, root/cemento-enamel junction [CEJ] presence) and sex as covariates and age as a time series variable. A four-way multivariate analysis of variance (MANOVA) comparing carious lesion type by sex, age, and periodontal disease presence was used to evaluate interaction between these variables. RESULTS: Individuals with carious lesions have greater survivorship than those without lesions. Males and females with crown lesions do not differ in survivorship from individuals without carious lesions. Females with root/CEJ lesions are characterized by the highest survivorship. A significant interaction was found for root/CEJ carious lesions by age, sex, and periodontal disease presence. Root/CEJ lesion formation in older males was not dependent upon periodontal disease presence, though dependence between these variables characterizes postmenopausal females. CONCLUSION: Sex-specific variation in crown lesions is not associated with reproductive life histories and likely reflects diet. By contrast, root/CEJ lesions form through pathways attributable to reproductive life histories, particularly age-induced periodontal disease in females. These results suggest the formation of carious lesions is complex, and in some cases, rooted in reproductive life histories.


Assuntos
Cárie Dentária/epidemiologia , Cárie Dentária/patologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paleodontologia , Doenças Periodontais , Fatores Sexuais , Coroa do Dente/patologia , Adulto Jovem
20.
J Hum Evol ; 142: 102731, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32199299

RESUMO

Enamel thickness remains an important morphological character in hominin systematics and is regularly incorporated into dietary reconstructions in hominin species. We expand upon a previous study of enamel thickness in mandibular molars by examining a large maxillary molar sample of Plio-Pleistocene hominins (n = 62) and a comparative sample of extant nonhuman apes (n = 48) and modern humans (n = 29). 2D mesial planes of section were generated through microtomography, and standard dental tissue variables were measured to calculate average enamel thickness (AET) and relative enamel thickness (RET). AET was also examined across the lingual, occlusal, and buccal regions of the crown. This study confirms previous findings of increasing enamel thickness throughout the Plio-Pleistocene, being thinnest in Australopithecus anamensis and peaking in Australopithecus boisei, with early Homo specimens, exhibiting intermediate enamel thickness. Agreeing with previous findings, 2D plane of section enamel thickness is found to be a poor taxonomic discriminator, with no statistically significant differences observed between fossil hominins. For fossil hominins, modern humans, and Pongo, the occlusal region of enamel was the thickest, and the lingual enamel thickness was greater than buccal. Pan and Gorilla present the opposite pattern with enamel being thinnest occlusally. Comparison at each molar position between the maxilla and mandible revealed very few significant differences in fossil hominins but some evidence of significantly thicker maxillary enamel (AET) in modern humans and thinner maxillary enamel in Pan (RET).


Assuntos
Esmalte Dentário/anatomia & histologia , Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Dente Molar/anatomia & histologia , Animais , Maxila/anatomia & histologia , Paleodontologia
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