Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.849
Filtrar
1.
J Forensic Odontostomatol ; 42(2): 39-49, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39244765

RESUMEN

BACKGROUND: Tooth wear is a non-pathological loss of hard tissues on the incisal and occlusal tooth surface. In archaeology, the loss of dental tissue through attrition is associated with living opportunities and habits, availability, characteristics and methods of food preparation. In forensics, tooth wear is used to estimate the dental age on cadavers. MATERIAL AND METHODS: For this study, we used an archaeological sample from two sample collections. In this study, tooth wear was compared in archaeological samples of well-preserved maxilla and mandible specimens (n=392) from Croatian coastal and continental populations from Late Antiquity (LA) and the Early Middle Ages (EMA). The computer system VistaMetrix 1.38 was used to analyse the abrasion and attrition of hard dental tissues. The Shapiro-Wilk and chi-square tests were performed for categorical data to test the difference between two historical periods and two geographical locations, while the Kruskal-Wallis test was performed for continuous data. RESULTS: There was a statistically significant difference in the proportion of tooth wear in total teeth area (P < 0.001) when comparing continental and coastal Croatia in LA and coastal Croatia between LA and EMA (P = 0.006 and P < 0.001, respectively). Samples from coastal Croatia from the LA period had the lowest percentage of tooth wear with a median of 8.35%, while samples from coastal Croatia from the EMA had the highest percentage of tooth wear with a median of 18.26%. Our results generally show greater tooth wear in the EMA period in male subjects. CONCLUSION: The results of the tooth wear research obtained with the Vista Metrix software can contribute to the study of life circumstances and changes that the analysed population has experienced in its historical development.


Asunto(s)
Desgaste de los Dientes , Humanos , Croacia , Masculino , Desgaste de los Dientes/patología , Desgaste de los Dientes/historia , Femenino , Historia Antigua , Paleodontología , Atrición Dental/patología , Historia Medieval
2.
Am J Biol Anthropol ; 185(1): e24998, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39032165

RESUMEN

OBJECTIVES: Grotta-Riparo di Uluzzo C (Apulia, southern Italy) is a pivotal site for investigating the evolution of the Middle Paleolithic and the earliest phases of the Upper Paleolithic in southern Italy, as the extensive stratigraphic record of this site includes a thick Mousterian sequence followed by the Uluzzian. Here, we investigate the taxonomic affinity of seven unpublished deciduous human teeth retrieved from the site of Uluzzo C in 1960. MATERIALS AND METHODS: The teeth are represented by seven plaster dental casts, which are housed at the Museo Civico di Paleontologia e Paletnologia in Maglie (Lecce, Apulia). The location of the original specimens remains unknown, rendering these casts the only human remains evidence yielded by Uluzzo C to date. Based on occlusal-view photographs and digital models of the casts, we examined the external morphology and morphometry of the teeth, comparing them to Homo sapiens and H. neanderthalensis samples. Through geometric morphometric methods and statistical analyses, we analyzed the crown outline of the deciduous molars. RESULTS: The teeth show morphological and morphometric features that are variably found in H. neanderthalensis, H. sapiens, or both. Specifically, crown outline analysis shows that all molars fall within H. neanderthalensis variability, except for Uluzzo 853 (lower right deciduous first molar), which falls within H. sapiens variability. DISCUSSION: This study provides the first taxonomic assessment of the hominin teeth from Uluzzo C. The results contribute additional insights into the Paleolithic peopling of southern Italy during a crucial period marked by the persistence of post-Tyrrhenian Neanderthal techno-complexes and the arrival of H. sapiens.


Asunto(s)
Fósiles , Hominidae , Italia , Animales , Hominidae/anatomía & histología , Humanos , Diente Primario/anatomía & histología , Hombre de Neandertal/anatomía & histología , Diente/anatomía & histología , Diente Molar/anatomía & histología , Paleodontología , Modelos Dentales
3.
Arch Oral Biol ; 164: 105985, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38703544

RESUMEN

OBJECTIVE: Oral status is an important indicator of past lifestyles. Determining the presence and extent of oral pathologies helps reconstruct average oral health, paramasticatory activities and diet of ancient and historical populations. DESIGN: In this study, the dental remains from the early medieval cemetery of Früebergstrasse in Baar (Canton of Zug, Switzerland) and the high medieval Dalheim cemetery (North Rhine-Westphalia, Germany) were analyzed. Caries, periodontal condition, periapical lesions, antemortem tooth loss, and enamel hypoplasia were assessed in 654 teeth (993 observable loci) from 68 individuals (Baar: n = 36; Dalheim: n = 32). RESULTS: The oral status of both populations was affected by age with higher values of tooth wear in advanced age individuals. High tooth wear values in both populations point towards the consumption of abrasive foods. Pronounced anterior tooth wear in Baar may also be due to non-masticatory tooth usage. Finally, possible nutritional deficiencies were hypothesized for the Baar population. A higher caries prevalence was observed in the Baar group, probably due to differences in carbohydrate intake. The oral conditions observed in the two studied populations exhibited several analogies, suggesting comparable lifestyles despite their separation in space and time. The only differences observed are related to the use of teeth as "tools" and are thus determined by behavioral choices rather than diverse socioeconomic factors. CONCLUSIONS: Using multiple dental parameters to examine the oral health of premodern individuals can provide useful insights into the interactions between humans and their environment, from dietary patterns to paramasticatory activities.


Asunto(s)
Paleodontología , Humanos , Historia Medieval , Masculino , Femenino , Adulto , Suiza , Alemania , Persona de Mediana Edad , Población Rural , Adolescente , Salud Bucal , Caries Dental/historia , Caries Dental/epidemiología , Desgaste de los Dientes/historia , Pérdida de Diente , Niño , Cementerios , Dieta/historia , Hipoplasia del Esmalte Dental/historia , Estilo de Vida
4.
Am J Biol Anthropol ; 184(4): e24948, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38733278

RESUMEN

OBJECTIVES: This study presents biological affinities between the last hunter-fisher-gatherers and first food-producing societies from the Nile Valley. We investigate odontometric and dental tissue proportion changes between these populations from the Middle Nile Valley and acknowledge the biological processes behind them. MATERIALS AND METHODS: Dental remains of 329 individuals from Nubia and Central Sudan that date from the Late Pleistocene to the mid-Holocene are studied. Using 3D imaging techniques, we investigated outer and inner metric aspects of upper central incisors, and first and second upper molars. RESULTS: Late Paleolithic and Mesolithic foragers display homogeneous crown dimensions, dental tissue proportions, and enamel thickness distribution. This contrasts with Neolithic trends for significant differences from earlier samples on inner and outer aspects. Finally, within the Neolithic sample differences are found between Nubian and Central Sudanese sites. DISCUSSION: Substantial dental variation appears to have occurred around 6000 bce in the Nile Valley, coinciding with the emergence of food-producing societies in the region. Archeological and biological records suggest little differences in dietary habits and dental health during this transition. Furthermore, the substantial variations identified here would have happened in an extremely short time, a few centuries at most. This does not support in situ diet-related adaptation. Rather, we suggest these data are consistent with some level of population discontinuity between the Mesolithic and Neolithic samples considered here. Complex settlement processes could also explain the differences between Nubia and Central Sudan, and with previous results based on nonmetric traits.


Asunto(s)
Paleodontología , Humanos , Historia Antigua , Sudán , Masculino , Femenino , Adulto , Diente/anatomía & histología , Diente/química , Diente Molar/anatomía & histología , Dieta/historia , Incisivo/anatomía & histología
5.
Int J Paleopathol ; 45: 55-61, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38688102

RESUMEN

OBJECTIVE: To analyze the overall frequency and inter-tooth patterns of caries in three populations from ancient cemeteries located along the western border of the Central Iranian Plateau as a means to explore whether the populations of Iran had greater access to fermentable sugars after the establishment of the great empires. MATERIALS: Dental collections from Kafarved-Varzaneh (Early Bronze Age, MNI=66), Estark-Joshaqan (Iron Age, MNI=57), Tappeh Poustchi (Timurid and Safavid Period, MNI=34), together with comparative data from NE Syria. METHODS: Frequencies of dental caries per tooth categories, location and size of carious lesions are analyzed using Smith's Mean Measure of Divergence, Correspondence Analysis, χ2 and Kruskal-Wallis tests. RESULTS: There are minimal differences in overall frequencies of carious lesions at Iranian sites, regardless of the chronology, but notable differences at Syrian sites. The inter-tooth pattern at the Iron Age cemetery in Estark appears distinctly different than the other Iranian sites and the comparative samples from Syria. CONCLUSIONS: Divergent subsistence strategies may be linked with different inter-tooth patterns since people buried at Estark were mobile herders, while the other cemeteries were used by settled farmers. SIGNIFICANCE: This comprehensive research on dental caries in three chronologically diverse populations in Iran sheds light on the association between dental caries and subsistence strategies, and introduces the Smith's Mean Measure of Divergence to explore inter-tooth carious patterns, which may prove useful to other researchers seeking to understand the relationships between subsistence, diet, and the presence of carious lesions. LIMITATIONS: The studied sample size is relatively small and therefore its temporal/regional distribution produces low-resolution results. SUGGESTIONS FOR FURTHER RESEARCH: More systematic research on the patterns of dental caries is necessary to produce more fine-grained reconstructions of diet and subsistence in Iran and around the globe.


Asunto(s)
Caries Dental , Humanos , Caries Dental/historia , Caries Dental/epidemiología , Caries Dental/patología , Irán/epidemiología , Historia Antigua , Siria/epidemiología , Paleodontología
6.
São Paulo; s.n; 20231213. 121 p.
Tesis en Portugués | LILACS, BBO - Odontología | ID: biblio-1519683

RESUMEN

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.


Asunto(s)
Paleodontología , Arqueología , Determinación de la Edad por los Dientes
7.
Arch Oral Biol ; 147: 105626, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36701952

RESUMEN

OBJECTIVE: This study examines changes in dental wear magnitude in the past ∼8000 years, i.e., since Mesolithic until the 19th century, in southwestern Iberia. Thus, it encompasses the transition from hunting-gathering to agro-pastoralism, and then to the industrialization of food production and pre-processing. DESIGN: Dental wear magnitude was scored in a total of 191 individuals and 1557 teeth from Mesolithic (individuals=56; teeth=643), Neolithic (individuals=35; teeth=169), Chalcolithic (individuals =35; teeth=221), Modern Age (individuals=17; teeth=209), and Late Modern Age (individuals=48; teeth=315) samples originating in southwestern Iberia (i.e., present central and southern Portugal) and according to the 8 levels ordinal scale of Smith (1984). RESULTS: Results show a general trend for decreased wear magnitude in these two major transitions and during this timespan (although the hunting-gathering - agro-pastoralism transition had larger impact). The only meaningful differences in wear rate were found between the Late Modern Age and all remaining samples. CONCLUSION: Dental wear generally decreased during this timespan (although wear magnitude was less impacted by the industrialization of food production and pre-processing). Our results are consistent with studies documenting skull morphological gracilization associated with reduced masticatory demands due to the adoption of softer diets.


Asunto(s)
Desgaste de los Dientes , Diente Impactado , Diente , Humanos , Paleodontología , Alimentos
8.
Sci Data ; 9(1): 396, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35817763

RESUMEN

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.


Asunto(s)
Bovinos , Fósiles , Animales , Bases de Datos Factuales , Paleodontología , Diente/diagnóstico por imagen
9.
São Paulo; s.n; 20220622. 87 p.
Tesis en Portugués | LILACS, BBO - Odontología | ID: biblio-1373159

RESUMEN

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.


Asunto(s)
Paleodontología , Arqueología , Determinación de la Edad por los Dientes
10.
PLoS One ; 16(11): e0258974, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34748581

RESUMEN

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.


Asunto(s)
Huesos , Fósiles , Paleodontología/tendencias , Diente , Animales , Arqueología/tendencias , Cuevas , Ciervos , Georgia (República) , Humanos
11.
J Hum Evol ; 158: 103047, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34403991

RESUMEN

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.


Asunto(s)
Fósiles , Hombre de Neandertal , Desgaste de los Dientes , Diente Primario/anatomía & histología , Animales , Historia Antigua , Humanos , Paleodontología , España
12.
J Hum Evol ; 158: 103046, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34332420

RESUMEN

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.


Asunto(s)
Mandrillus , Diente/anatomía & histología , Animales , Femenino , Gabón , Masculino , Mandrillus/fisiología , Paleodontología , Reproducción
14.
Science ; 372(6546): 1105-1107, 2021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34083491

RESUMEN

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.


Asunto(s)
Ecosistema , Extinción Biológica , Tiburones , Animales , Peces , Fósiles , Sedimentos Geológicos , Océanos y Mares , Paleodontología , Diente/anatomía & histología
15.
Science ; 371(6535): 1253-1256, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33737486

RESUMEN

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.


Asunto(s)
Evolución Biológica , Fósiles , Tiburones/anatomía & histología , Tiburones/fisiología , Aletas de Animales/anatomía & histología , Animales , Ecosistema , Elasmobranquios/anatomía & histología , Elasmobranquios/fisiología , Conducta Alimentaria , México , Océanos y Mares , Paleodontología , Plancton , Tiburones/clasificación , Natación , Diente/anatomía & histología
16.
PLoS One ; 16(3): e0247969, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33690686

RESUMEN

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.


Asunto(s)
Dinosaurios/anatomía & histología , Desgaste de los Dientes/patología , Adaptación Fisiológica , Animales , Evolución Biológica , China , Fósiles/anatomía & histología , Historia Antigua , Maxilares/anatomía & histología , Mandíbula/anatomía & histología , Masticación/fisiología , Paleodontología/métodos , Diente/anatomía & histología , Desgaste de los Dientes/veterinaria
17.
Am J Phys Anthropol ; 174(4): 832-838, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33522597

RESUMEN

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.


Asunto(s)
Diente Molar/patología , Paleodontología/métodos , Atrición Dental/patología , Humanos , Fotograbar
19.
J Hum Evol ; 152: 102939, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33517134

RESUMEN

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.


Asunto(s)
Fósiles/anatomía & histología , Hombre de Neandertal/anatomía & histología , Diente/anatomía & histología , Animales , Evolución Biológica , Islas Anglonormandas , Femenino , Paleodontología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA