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1.
Nature ; 574(7776): 103-107, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31511700

RESUMO

The sequencing of ancient DNA has enabled the reconstruction of speciation, migration and admixture events for extinct taxa1. However, the irreversible post-mortem degradation2 of ancient DNA has so far limited its recovery-outside permafrost areas-to specimens that are not older than approximately 0.5 million years (Myr)3. By contrast, tandem mass spectrometry has enabled the sequencing of approximately 1.5-Myr-old collagen type I4, and suggested the presence of protein residues in fossils of the Cretaceous period5-although with limited phylogenetic use6. In the absence of molecular evidence, the speciation of several extinct species of the Early and Middle Pleistocene epoch remains contentious. Here we address the phylogenetic relationships of the Eurasian Rhinocerotidae of the Pleistocene epoch7-9, using the proteome of dental enamel from a Stephanorhinus tooth that is approximately 1.77-Myr old, recovered from the archaeological site of Dmanisi (South Caucasus, Georgia)10. Molecular phylogenetic analyses place this Stephanorhinus as a sister group to the clade formed by the woolly rhinoceros (Coelodonta antiquitatis) and Merck's rhinoceros (Stephanorhinus kirchbergensis). We show that Coelodonta evolved from an early Stephanorhinus lineage, and that this latter genus includes at least two distinct evolutionary lines. The genus Stephanorhinus is therefore currently paraphyletic, and its systematic revision is needed. We demonstrate that sequencing the proteome of Early Pleistocene dental enamel overcomes the limitations of phylogenetic inference based on ancient collagen or DNA. Our approach also provides additional information about the sex and taxonomic assignment of other specimens from Dmanisi. Our findings reveal that proteomic investigation of ancient dental enamel-which is the hardest tissue in vertebrates11, and is highly abundant in the fossil record-can push the reconstruction of molecular evolution further back into the Early Pleistocene epoch, beyond the currently known limits of ancient DNA preservation.


Assuntos
DNA Antigo/análise , Esmalte Dentário/metabolismo , Fósseis , Perissodáctilos/classificação , Perissodáctilos/genética , Filogenia , Proteoma/genética , Proteômica , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Teorema de Bayes , História Antiga , Humanos , Masculino , Perissodáctilos/metabolismo , Fosforilação/genética , Proteoma/análise
2.
J Hum Evol ; 171: 103249, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36116366

RESUMO

There are many hypotheses regarding influences on the early hominin biogeographic spread into Eurasia; among them is increased meat-eating. Dmanisi in Georgia is one of the rare Early Pleistocene sites in Eurasia, and here we present primary information and analysis of the medium and large mammal taphonomy, contributing information about site formation and the hominins' interaction with the fauna. Nearly 85% of the specimens come from the B1 stratum. Relative abundances of mammal families demonstrate some bias toward carnivores, especially Canis borjgali, and diverse Felidae species. Bones display little weathering. Post-depositional surface modifications and matrix obscure many bone surfaces, but carnivore tooth marking is the most common bone surface modification from the nutritive taphonomic phase. Tooth pits are large, in the size range of those made by modern Crocuta crocuta and Panthera leo. Breakage variables indicate most breaks occurred while the bones were still fresh, many by carnivore consumption. Fairly even limb bone representation of herbivores suggests carcasses were introduced to the site nearly whole. Hominin tool marks are present in low frequencies, but they suggest a variety of behaviors. These marks are found on Equus, Palaeotragus, Bison, large cervids, Pseudodama, Canis, and Mammuthus. Some were made by filleting proximal limb segments, and so are likely indicative of early access to carcasses, while other marks suggest scavenging. The Homo taphonomic variables resemble the rest of the taphonomic signatures from the site with little weathering, a slightly higher percentage of their bones are whole, but only a few have probable carnivore damage. The assemblage characteristics are compared to modern actualistic and experimental assemblages, and it is concluded that Dmanisi presents a palimpsest of hyena denning, felid activity, hominin meat-eating and likely natural deaths.


Assuntos
Carnívoros , Hominidae , Dente , Animais , Fósseis , Georgia , Mamíferos
3.
Nature ; 434(7034): 717-8, 2005 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-15815618

RESUMO

The site of Dmanisi in the Eurasian republic of Georgia has yielded striking hominin, faunal and archaeological material as evidence for the presence of early Homo outside Africa 1.77 million years ago, documenting an important episode in human evolution. Here we describe a beautifully preserved skull and jawbone from a Dmanisi hominin of this period who had lost all but one tooth several years before death. This specimen not only represents the earliest case of severe masticatory impairment in the hominin fossil record to be discovered so far, but also raises questions about alternative subsistence strategies in early Homo.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Crânio/anatomia & histologia , Perda de Dente/patologia , Animais , República da Geórgia , História Antiga , Hominidae/fisiologia , Mandíbula/anatomia & histologia , Mandíbula/patologia , Mastigação/fisiologia , Crânio/patologia , Dente/patologia , Dente/fisiologia , Perda de Dente/fisiopatologia
4.
Anat Rec A Discov Mol Cell Evol Biol ; 288(11): 1146-57, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17031841

RESUMO

Newly discovered Homo remains, stone artifacts, and animal fossils from Dmanisi, Republic of Georgia, provide a basis for better understanding patterns of hominin evolution and behavior in Eurasia ca. 1.77 million years ago. Here we describe a fourth skull that is nearly complete, lacking all but one of its teeth at the time of death. Both the maxillae and the mandible exhibit extensive bone loss due to resorption. This individual is similar to others from the site but supplies information about variation in brain size and craniofacial anatomy within the Dmanisi paleodeme. Although this assemblage presents numerous primitive characters, the Dmanisi skulls are best accommodated within the species H. erectus. On anatomical grounds, it is argued that the relatively small-brained and lightly built Dmanisi hominins may be ancestral to African and Far Eastern branches of H. erectus showing more derived morphology.


Assuntos
Encéfalo/anatomia & histologia , Hominidae/anatomia & histologia , Crânio/anatomia & histologia , Adulto , Animais , Arqueologia , Remodelação Óssea , Cefalometria , Fósseis , Osso Frontal/anatomia & histologia , República da Geórgia , História Antiga , Hominidae/classificação , Humanos , Masculino , Mandíbula/anatomia & histologia , Processo Mastoide/anatomia & histologia , Maxila/anatomia & histologia , Osso Occipital/anatomia & histologia , Tamanho do Órgão , Paleontologia/métodos , Filogenia , Caracteres Sexuais , Dente
5.
Science ; 297(5578): 85-9, 2002 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-12098694

RESUMO

Another hominid skull has been recovered at Dmanisi (Republic of Georgia) from the same strata in which hominid remains have been reported previously. The Dmanisi site dated to approximately 1.75 million years ago has now produced craniofacial portions of several hominid individuals, along with many well-preserved animal fossils and quantities of stone artifacts. Although there are certain anatomical differences among the Dmanisi specimens, the hominids do not clearly represent more than one taxon. We assign the new skull provisionally to Homo erectus (=ergaster). The Dmanisi specimens are the most primitive and small-brained fossils to be grouped with this species or any taxon linked unequivocally with genus Homo and also the ones most similar to the presumed habilis-like stem. We suggest that the ancestors of the Dmanisi population dispersed from Africa before the emergence of humans identified broadly with the H. erectus grade.


Assuntos
Fósseis , Hominidae , Crânio/anatomia & histologia , África , Animais , Antropologia Física , Encéfalo/anatomia & histologia , Cefalometria , Emigração e Imigração , Osso Frontal/anatomia & histologia , Sedimentos Geológicos , República da Geórgia , Hominidae/anatomia & histologia , Hominidae/classificação , Humanos , Mandíbula/anatomia & histologia , Osso Nasal/anatomia & histologia , Órbita/anatomia & histologia , Osso Parietal/anatomia & histologia , Roedores , Osso Temporal/anatomia & histologia , Dente
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