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1.
J Morphol ; 284(9): e21626, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37585227

RESUMO

Extinct woolly rhinoceroses were iconic representatives of the Late Pleistocene mammoth fauna of Eurasia. These animals were characterized by two huge keratinous horns. In adults, the length of the nasal horn often exceeded one meter. The nasal horn of Coelodonta was characterized by an unusual feature for rhinoceroses-the width of its base was considerably narrower than the width of the rugosity area on the nasal bones of the skull. In this study, a new discovery of woolly rhinoceros' nasal horn in the permafrost of Yakutia is described. This specimen shows that the shape of the base of the woolly rhino's nasal horn corresponds well to the shape (length and width) of the nasal rugosity area. The base of the nasal horn of Coelodonta was markedly elongated anteroposteriorly compared to extant rhinoceroses. Its length was about 150% of the width. We therefore suggest that the narrower shape of the nasal horn base in the majority of previously found specimens was associated with secondary damage after burial caused by maceration.


Assuntos
Mamutes , Pergelissolo , Animais , Cabeça , Nariz , Perissodáctilos/anatomia & histologia , Crânio , Mamutes/anatomia & histologia
2.
Nature ; 617(7961): 533-539, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37138076

RESUMO

Hormones in biological media reveal endocrine activity related to development, reproduction, disease and stress on different timescales1. Serum provides immediate circulating concentrations2, whereas various tissues record steroid hormones accumulated over time3,4. Hormones have been studied in keratin, bones and teeth in modern5-8 and ancient contexts9-12; however, the biological significance of such records is subject to ongoing debate10,13-16, and the utility of tooth-associated hormones has not previously been demonstrated. Here we use liquid chromatography with tandem mass spectrometry paired with fine-scale serial sampling to measure steroid hormone concentrations in modern and fossil tusk dentin. An adult male African elephant (Loxodonta africana) tusk shows periodic increases in testosterone that reveal episodes of musth17-19, an annually recurring period of behavioural and physiological changes that enhance mating success20-23. Parallel assessments of a male woolly mammoth (Mammuthus primigenius) tusk show that mammoths also experienced musth. These results set the stage for wide-ranging studies using steroids preserved in dentin to investigate development, reproduction and stress in modern and extinct mammals. Because dentin grows by apposition, resists degradation, and often contains growth lines, teeth have advantages over other tissues that are used as records of endocrine data. Given the low mass of dentin powder required for analytical precision, we anticipate dentin-hormone studies to extend to smaller animals. Thus, in addition to broad applications in zoology and palaeontology, tooth hormone records could support medical, forensic, veterinary and archaeological studies.


Assuntos
Elefantes , Fósseis , Mamutes , Testosterona , Dente , Animais , Masculino , Elefantes/anatomia & histologia , Elefantes/metabolismo , Mamutes/anatomia & histologia , Mamutes/metabolismo , Esteroides/análise , Esteroides/metabolismo , Testosterona/análise , Testosterona/metabolismo , Dente/química , Dente/metabolismo , Dentina/química , Dentina/metabolismo
3.
Appl Radiat Isot ; 166: 109292, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32828010

RESUMO

At the time when the importance of the interdisciplinary research increases, the nuclear analytical techniques supported by the small research reactors represent a useful tool for investigation of human society, culture, history etc. The historical, archaeological, and palaeontological samples and objects of cultural heritage can be easily studied using the radioanalytical methods such as the neutron activation analysis. This paper deals with the detailed investigation of fragments of mammoth remains from the Mid-Upper Palaeolithic site Pavlov VI by means of the instrumental neutron activation analysis at the Training Reactor VR-1 of the Czech Technical University in Prague. Six mammoth hard tissue samples (fragments of bones, tusk, and molar) from the Institute of Archaeology of the Czech Academy of Sciences were irradiated in the dry vertical irradiation channel with thermal neutron field (φ=2×109cm-2s-1) at maximum reactor power (80 W). The activated mammoth samples were analysed employing the nuclear γ-spectrometry and semiconductor HPGe detector, and the composition of the remains was determined (qualitative and quantitative analysis). The presence of Na, Cl, K, As, Fe, Sr, Mn, Br, I, Ba, and U was revealed in studied mammoth samples. Based on obtained production rates, the concentrations of Fe, Sr, Na, K, As, and U were determined. The results presented in this paper show clearly that the low-power Training Reactor VR-1 is excellent tool for the neutron activation analysis experiments within the interdisciplinary research and can provide experimental data important for archaeologists and palaeontologists.


Assuntos
Mamutes/metabolismo , Análise de Ativação de Nêutrons/métodos , Paleontologia/métodos , Animais , República Tcheca , Elementos Químicos , Fósseis , Mamutes/anatomia & histologia , Metais/análise , Reatores Nucleares , Radioisótopos/análise , Espectrometria gama
4.
Surg Radiol Anat ; 41(5): 583-588, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30656416

RESUMO

PURPOSE: The groove of the vertebral artery on the posterior arch of the atlas (sulcus arteriae vertebralis) may become a complete or partial osseous foramen: the arcuate foramen. The presence of a complete or partial arcuate foramen is a rare anatomical variant described in a minority of patients and it seems to be associated with vertigo, vertebro-basilar insufficiency, posterior circulation strokes, and musculoskeletal pain. As the number and morphology of cervical vertebrae is highly preserved, we questioned about its significance from an evolutionary point of view. We thus investigated through an extensive literature review if the arcuate foramen is a pure anatomical variation shape or if it might represent an adaptation legacy. METHODS: We observed five atlas of an extinct species, the Late Pleistocene Mammoths (M. primigenius), and we compared them with five atlas of a closely related existent species, the African elephant (L. africana). RESULTS: All the mammoths' atlas had an arcuate foramen through which the vertebral artery passed before turning anteriorly and becoming intradural. This foramen was not present in elephants' atlas, where only a groove was observed, such as in the majority of patients. CONCLUSION: We would like to raise the hypothesis that this peculiar morphology of mammoths' atlas might have contributed, in association with other factors, to their precocious extinction and that the arcuate foramen might represent a disadvantage in the evolutionary process, with a low prevalence in humans being the result of a natural selection.


Assuntos
Variação Anatômica , Atlas Cervical/anatomia & histologia , Elefantes/anatomia & histologia , Mamutes/anatomia & histologia , Artéria Vertebral/anatomia & histologia , Animais , Evolução Biológica
5.
Angew Chem Int Ed Engl ; 57(25): 7428-7432, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29522651

RESUMO

Among the earliest Homo sapiens societies in Eurasia, the Aurignacian phase of the Early Upper Paleolithic, approximately 40 000-30 000 years ago, mammoth ivory assumed great social and economic significance, and was used to create hundreds of personal ornaments as well as the earliest known works of three-dimensional figurative art in the world. This paper reports on the results of micro-PIXE/PIGE analyses of mammoth-ivory artifacts and debris from five major sites of Aurignacian ivory use. Patterns of variable fluorine content indicate regionally distinctive strategies of ivory procurement that correspond to apparent differences in human-mammoth interactions. Preserved trace elements (Br, Sr, Zn) indicate that differences at the regional level are applicable to sourcing Paleolithic ivory at the regional scale.


Assuntos
Arqueologia , Mamutes/anatomia & histologia , Espectrometria por Raios X/métodos , Dente/química , Animais , Oligoelementos/análise
6.
Sci Rep ; 7(1): 16620, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29192242

RESUMO

Large quantities of impact-related microspherules have been found in fine-grained sediments retained within seven out of nine, radiocarbon-dated, Late Pleistocene mammoth (Mammuthus primigenius) and bison (Bison priscus) skull fragments. The well-preserved fossils were recovered from frozen "muck" deposits (organic-rich silt) exposed within the Fairbanks and Klondike mining districts of Alaska, USA, and the Yukon Territory, Canada. In addition, elevated platinum abundances were found in sediment analysed from three out of four fossil skulls. In view of this new evidence, the mucks and their well-preserved but highly disrupted and damaged vertebrate and botanical remains are reinterpreted in part as blast deposits that resulted from several episodes of airbursts and ground/ice impacts within the northern hemisphere during Late Pleistocene time (~46-11 ka B.P.). Such a scenario might be explained by encounters with cometary debris in Earth-crossing orbits (Taurid Complex) that was generated by fragmentation of a large short-period comet within the inner Solar System.


Assuntos
Fósseis , Mamutes , Alaska , Animais , Geografia , Mamutes/anatomia & histologia , Plantas , Vertebrados , Yukon
7.
Curr Biol ; 27(22): 3505-3510.e3, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29103934

RESUMO

While present-day taxa are valuable proxies for understanding the biology of extinct species, it is also crucial to examine physical remains in order to obtain a more comprehensive view of their behavior, social structure, and life histories [1, 2]. For example, information on demographic parameters such as age distribution and sex ratios in fossil assemblages can be used to accurately infer socioecological patterns (e.g., [3]). Here we use genomic data to determine the sex of 98 woolly mammoth (Mammuthus primigenius) specimens in order to infer social and behavioral patterns in the last 60,000 years of the species' existence. We report a significant excess of males among the identified samples (69% versus 31%; p < 0.0002). We argue that this male bias among mammoth remains is best explained by males more often being caught in natural traps that favor preservation. We hypothesize that this is a consequence of social structure in proboscideans, which is characterized by matriarchal hierarchy and sex segregation. Without the experience associated with living in a matriarchal family group, or a bachelor group with an experienced bull, young or solitary males may have been more prone to die in natural traps where good preservation is more likely.


Assuntos
Mamutes/genética , Análise para Determinação do Sexo/métodos , Determinação do Sexo pelo Esqueleto/métodos , Animais , Comportamento Animal , Elefantes/genética , Extinção Biológica , Feminino , Fósseis , Genoma , Genômica , Masculino , Mamutes/anatomia & histologia , Filogenia , Análise de Sequência de DNA , Razão de Masculinidade , Comportamento Sexual/fisiologia , Comportamento Social
8.
Science ; 351(6270): 260-3, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26816376

RESUMO

Archaeological evidence for human dispersal through northern Eurasia before 40,000 years ago is rare. In west Siberia, the northernmost find of that age is located at 57°N. Elsewhere, the earliest presence of humans in the Arctic is commonly thought to be circa 35,000 to 30,000 years before the present. A mammoth kill site in the central Siberian Arctic, dated to 45,000 years before the present, expands the populated area to almost 72°N. The advancement of mammoth hunting probably allowed people to survive and spread widely across northernmost Arctic Siberia.


Assuntos
Atividades Humanas , Migração Humana , Mamutes/lesões , Animais , Antropologia , Regiões Árticas , Osso e Ossos/anatomia & histologia , Osso e Ossos/lesões , Europa (Continente) , Humanos , Mamutes/anatomia & histologia , Paleontologia , Sibéria
9.
Dokl Biol Sci ; 471(1): 291-295, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28058607

RESUMO

Hair microstructure of the first calf of the woolly rhinoceros Coelodonta antiquitatis found in Sakha in 2014 (the neck and hind leg hair) was examined by the light and electron scanning microscopy. The calf hair features were compared with those of two adults studied earlier. The calf coat color was much lighter than in adults, from pale ashy to blond. The extent of hair differentiation, dimensional and pigmentation indices were lower in the calf than in adult rhinoceroses. There was no medulla in the calf hairs, while in those of adults it was occasionally found. The cortical and cuticular layer microstructure was similar in all the animals compared. In both calf and adult hairs, there were traces of mechanical damage.


Assuntos
Mamutes/anatomia & histologia , Perissodáctilos/anatomia & histologia , Lã/ultraestrutura , Animais , Cor , Microscopia Eletrônica de Varredura , Federação Russa
10.
Science ; 350(6262): 805-9, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26564853

RESUMO

Mammoths provide a detailed example of species origins and dispersal, but understanding has been impeded by taxonomic confusion, especially in North America. The Columbian mammoth Mammuthus columbi was thought to have evolved in North America from a more primitive Eurasian immigrant. The earliest American mammoths (1.5 million years ago), however, resemble the advanced Eurasian M. trogontherii that crossed the Bering land bridge around that time, giving rise directly to M. columbi. Woolly mammoth M. primigenius later evolved in Beringia and spread into Europe and North America, leading to a diversity of morphologies as it encountered endemic M. trogontherii and M. columbi, respectively. In North America, this included intermediates ("M. jeffersonii"), suggesting introgression of M. primigenius with M. columbi. The lineage illustrates the dynamic interplay of local adaptation, dispersal, and gene flow in the evolution of a widely distributed species complex.


Assuntos
Evolução Biológica , Mamutes/classificação , Adaptação Fisiológica , Migração Animal , Animais , Europa (Continente) , Fósseis , Fluxo Gênico , Mamutes/anatomia & histologia , Mamutes/genética , Dente Molar/anatomia & histologia , América do Norte , Desgaste dos Dentes/patologia
13.
J Comp Neurol ; 523(16): 2326-43, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26011110

RESUMO

This study presents the results of an examination of the mummified brain of a pleistocene woolly mammoth (Mammuthus primigenius) recovered from the Yakutian permafrost in Siberia, Russia. This unique specimen (from 39,440-38,850 years BP) provides the rare opportunity to compare the brain morphology of this extinct species with a related extant species, the African elephant (Loxodonta africana). An anatomical description of the preserved brain of the woolly mammoth is provided, along with a series of quantitative analyses of various brain structures. These descriptions are based on visual inspection of the actual specimen as well as qualitative and quantitative comparison of computed tomography imaging data obtained for the woolly mammoth in comparison with magnetic resonance imaging data from three African elephant brains. In general, the brain of the woolly mammoth specimen examined, estimated to weigh between 4,230 and 4,340 g, showed the typical shape, size, and gross structures observed in extant elephants. Quantitative comparative analyses of various features of the brain, such as the amygdala, corpus callosum, cerebellum, and gyrnecephalic index, all indicate that the brain of the woolly mammoth specimen examined has many similarities with that of modern African elephants. The analysis provided here indicates that a specific brain type representative of the Elephantidae is likely to be a feature of this mammalian family. In addition, the extensive similarities between the woolly mammoth brain and the African elephant brain indicate that the specializations observed in the extant elephant brain are likely to have been present in the woolly mammoth.


Assuntos
Encéfalo/anatomia & histologia , Elefantes/anatomia & histologia , Mamutes/anatomia & histologia , Múmias/patologia , Animais , Encéfalo/diagnóstico por imagem , Feminino , Imageamento por Ressonância Magnética , Masculino , Meninges/anatomia & histologia , Meninges/diagnóstico por imagem , Múmias/diagnóstico por imagem , Tamanho do Órgão , Tomografia Computadorizada por Raios X
15.
Integr Zool ; 9(4): 471-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24148659

RESUMO

The frozen bodies of a young woolly mammoth (Mammuthus primigenius), a wild horse (Equus sp.) and a steppe bison (Bison priscus) were recently found in the northern Yakutia (northeastern Siberia). All specimens have preserved bones, skin and soft tissues. Whereas the woolly mammoth and the Pleistocene horse were represented by partial frozen bodies, the steppe bison body was recovered in an absolutely complete state. All specimens were found frozen in the permafrost, with some of the tissues mummified. The wild horse and steppe bison are of Holocene age, and the mammoth is of Late Pleistocene age.


Assuntos
Bison/anatomia & histologia , Fósseis , Cavalos/anatomia & histologia , Mamutes/anatomia & histologia , Animais , Sibéria
17.
Homo ; 64(2): 89-103, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23415376

RESUMO

The primary aim of this study was to conduct a taxonomic assessment of the second of three isolated human teeth found in the Stajnia Cave (north of the Carpathians, Poland) in 2008. The specimen was located near a human tooth (S5000), which was identified by Urbanowski et al. (2010) as a Neanderthal permanent upper molar. Both of these teeth were excavated from the D2 layer, which belongs to the D stratigraphic complex comprising the archaeological assemblage associated with the Micoquian tradition. An Ursus spelaeus bone and Mammuthus primigenius tooth that were also excavated from the D2 layer were dated to >49,000 years BP (by AMS (14)C) and 52.9 ka BP (by U-Th), respectively. The sediment overlying stratigraphic complex D was dated to 45.9 ka BP by the OSL method. The S4300 tooth is a lower first or second permanent molar belonging to an individual other than that who once possessed the S5000 tooth. The S4300 tooth exhibits a combination of traits typical of Neanderthal lower molars, including a mid-trigonid crest, large anterior fovea, taurodontism and subvertical grooves on the interproximal face, indicating that this tooth belonged to a Neanderthal individual. The S4300 tooth from Stajnia Cave is one of the oldest human remains found in Poland.


Assuntos
Dente Molar/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Animais , Fósseis , História Antiga , Humanos , Mamutes/anatomia & histologia , Homem de Neandertal/classificação , Paleodontologia , Polônia , Ursidae/anatomia & histologia
18.
J Morphol ; 273(12): 1406-23, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22949298

RESUMO

The chequered pattern (often called Schreger pattern), which can be seen by unaided eye on transverse profiles of several proboscidean tusks and which can be emphasized by the spreading pattern of the cracks or by mineral discoloration, is an autapomorph feature of the clade Elephantoidea. The pattern differs among proboscidean taxa; therefore, it allows the coarse differentiation of elephants, mammoths, and some other basal groups. Such identification methods could facilitate efforts concerned with protection of the remaining elephant populations through ivory trade restrictions, since the tooth dentine from extinct Mammuthusprimigenius and from extant Loxodontaafricana and Elephasmaximus are the most common raw materials of the ivory carvings. The aim of this study was to show the internal structure of proboscidean ivory and to revise the existing theories on the aforementioned pattern of the elephantoids with reflections on the events which lead to the development of this microstructure. Thin sections and natural crack surfaces with various orientations of M.primigenius, Elephasantiquus, Prodeinotherium, and Deinotherium tusk fragments were used to produce a three-dimensional model which explains the features on all profiles. The "phase shift" model is introduced, which assumes a sinusoid undulation of the dentinal tubules in radial profiles in the case of elephantoids. The model was confirmed by photomicrographs, scanning electron microscopic images, interpretation of natural crack surfaces, and radial displacement analysis of the dentinal tubules. The latter proved that the adjacent waves are not in the same phase. Several new nondestructive distinguishing methods are described here on the basis of the correlation between some microscopic and macroscopic features related to the Schreger pattern.


Assuntos
Dentina/ultraestrutura , Elefantes/anatomia & histologia , Mamutes/anatomia & histologia , Dente/anatomia & histologia , Animais , Dentina/anatomia & histologia , Dentina/química , Elefantes/classificação , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Dente/química , Dente/ultraestrutura
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