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1.
Nature ; 521(7552): 310-5, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25993961

RESUMO

Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone's fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name 'Lomekwian', which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.


Assuntos
Hominidae , Comportamento de Utilização de Ferramentas , Animais , Arqueologia , Evolução Biológica , Meio Ambiente , Fósseis , História Antiga , Quênia , Paleontologia , Tecnologia/história , Fatores de Tempo
2.
Nature ; 477(7362): 82-5, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-21886161

RESUMO

The Acheulian is one of the first defined prehistoric techno-complexes and is characterized by shaped bifacial stone tools. It probably originated in Africa, spreading to Europe and Asia perhaps as early as ∼1 million years (Myr) ago. The origin of the Acheulian is thought to have closely coincided with major changes in human brain evolution, allowing for further technological developments. Nonetheless, the emergence of the Acheulian remains unclear because well-dated sites older than 1.4 Myr ago are scarce. Here we report on the lithic assemblage and geological context for the Kokiselei 4 archaeological site from the Nachukui formation (West Turkana, Kenya) that bears characteristic early Acheulian tools and pushes the first appearance datum for this stone-age technology back to 1.76 Myr ago. Moreover, co-occurrence of Oldowan and Acheulian artefacts at the Kokiselei site complex indicates that the two technologies are not mutually exclusive time-successive components of an evolving cultural lineage, and suggests that the Acheulian was either imported from another location yet to be identified or originated from Oldowan hominins at this vicinity. In either case, the Acheulian did not accompany the first human dispersal from Africa despite being available at the time. This may indicate that multiple groups of hominins distinguished by separate stone-tool-making behaviours and dispersal strategies coexisted in Africa at 1.76 Myr ago.


Assuntos
Evolução Cultural , Sedimentos Geológicos/análise , Hominidae/fisiologia , Animais , Arqueologia , Evolução Biológica , Fósseis , Humanos , Quênia
3.
PLoS One ; 17(2): e0261282, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35148324

RESUMO

North African coastal Middle Stone Age (MSA) sites are key to study the development and expansion of early H. sapiens. El Mnasra cave on the Atlantic coast of Morocco (Témara region) is a crucial site associated with MSA archaeological materials considered advanced cognitive hallmarks of behavioural innovation, such as numerous Nassariidae perforated shells, hematite pigments, bones industry and coastal resources exploitation. We provide new trapped-charges dates (OSL and combined US-ESR ages). Our Bayesian modelling strengthens the new lithostratigraphic interpretation of the cave stratigraphic units (US) and we propose an updated chronostratigraphic model for the Middle Stone Age archaeo-sequence of El Mnasra Cave. We confirm a human presence between 124-104 ka, earlier than what the previous OSL and US-ESR data showed. Our time range intervals allowed us to also extend the age of the MSA occupations considerably to the MIS 4/3 (~62-30 ka), marked by the disappearance of the Nassariidae perforated shells. Outstandingly, our model pushed back the age of the largest record of Nassariidae perforated shells and placed the age of their use by the Aterian groups at El Mnasra from the MIS 5d-5b (~115-94 ka).


Assuntos
Arqueologia , Fósseis , Animais , Teorema de Bayes , Cavernas , Medições Luminescentes , Marrocos , Dente/química
4.
Zootaxa ; 4927(3): zootaxa.4927.3.4, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33756701

RESUMO

Documenting recent extinction events against the backdrop of increasing human-induced environmental pressure is complicated by the lack of historical and subfossil evidence for most parts of the world. This paucity of data renders it particularly difficult to evaluate the human impact on fragile environments, such as small islands, that may have been heavily altered by historical human exploitation. Here we describe a new species of an extinct Leiocephalus lizard from Guadeloupe, Leiocephalus roquetus sp. nov. based on recent discoveries of both a previously undocumented historically taxidermy specimen and of a large assemblage of subfossil bone remains from La Désirade Island. This new species presents a primitive morphology compared to all extant species of its genus and provides evidence for the past existence of a Lesser Antillean clade of Leiocephalus lizards that was completely wiped out in the centuries following the European colonization of these islands. Our study demonstrates how paleontological approaches can help to better understand the history of human environmental impact as well as the degree of degradation of modern ecosystems.


Assuntos
Fósseis , Lagartos , Animais , Ecossistema , Guadalupe , Ilhas , Lagartos/anatomia & histologia
5.
Sci Adv ; 7(21)2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34138736

RESUMO

Large-scale extinction is one of the defining challenges of our time, as human processes fundamentally and irreversibly reshape global ecosystems. While the extinction of large animals with popular appeal garners widespread public and research interest, the importance of smaller, less "charismatic" species to ecosystem health is increasingly recognized. Benefitting from systematically collected fossil and archaeological archives, we examined snake and lizard extinctions in the Guadeloupe Islands of the Caribbean. Study of 43,000 bone remains across six islands revealed a massive extinction of 50 to 70% of Guadeloupe's snakes and lizards following European colonization. In contrast, earlier Indigenous populations coexisted with snakes and lizards for thousands of years without affecting their diversity. Study of archaeological remains provides insights into the causes of snake and lizard extinctions and shows that failure to consider fossil-derived data probably contributes to substantial underestimation of human impacts to global biodiversity.

6.
Proc Biol Sci ; 273(1602): 2697-702, 2006 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-17015330

RESUMO

Tracks of marine animals in the wild, now increasingly acquired by electronic tagging of individuals, are of prime interest not only to identify habitats and high-risk areas, but also to gain detailed information about the behaviour of these animals. Using recent satellite-derived current estimates and leatherback turtle (Dermochelys coriacea) tracking data, we demonstrate that oceanic currents, usually neglected when analysing tracking data, can substantially distort the observed trajectories. Consequently, this will affect several important results deduced from the analysis of tracking data, such as the evaluation of the orientation skills and the energy budget of animals or the identification of foraging areas. We conclude that currents should be systematically taken into account to ensure the unbiased interpretation of tracking data, which now play a major role in marine conservation biology.


Assuntos
Comportamento Animal , Ecossistema , Natação , Tartarugas/fisiologia , Movimentos da Água , Animais , Oceanos e Mares
7.
Proc Natl Acad Sci U S A ; 103(33): 12643-8, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16894152

RESUMO

The Châtelperronian is a Neandertal-associated archeological culture featuring ornaments and decorated bone tools. It is often suggested that such symbolic items do not imply that Neandertals had modern cognition and stand instead for influences received from coeval, nearby early modern humans represented by the Aurignacian culture, whose precocity would be proven by stratigraphy and radiocarbon dates. The Grotte des Fées at Châtelperron (France) is the remaining case of such a potential Châtelperronian-Aurignacian contemporaneity, but reanalysis shows that its stratification is poor and unclear, the bone assemblage is carnivore-accumulated, the putative interstratified Aurignacian lens in level B4 is made up for the most part of Châtelperronian material, the upper part of the sequence is entirely disturbed, and the few Aurignacian items in levels B4-5 represent isolated intrusions into otherwise in situ Châtelperronian deposits. As elsewhere in southwestern Europe, this evidence confirms that the Aurignacian postdates the Châtelperronian and that the latter's cultural innovations are better explained as the Neandertals' independent development of behavioral modernity.


Assuntos
Arqueologia , Comportamento , Cultura , Antropologia Física , Europa (Continente) , Humanos
8.
Proc Natl Acad Sci U S A ; 102(20): 7085-90, 2005 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-15878988

RESUMO

In 2002, a Neandertal partial femoral diaphysis was discovered at Les Rochers-de-Villeneuve (Vienne, France). Radiocarbon dated to approximately 40,700 14C years before present, this specimen is one of the most recent Middle Paleolithic Neandertals. The diaphysis derives from an archeological level indicating alternating human and carnivore (mostly hyena) occupation of the cave, reinforcing the close proximity and probable competition of Middle Paleolithic humans with large carnivores for resources and space. Morphological aspects of the diaphysis and ancient DNA extracted from it indicate that it is aligned with the Neandertals and is distinct from early modern humans. However, its midshaft cortical bone distribution places it between other Middle Paleolithic Neandertals and the Châtelperronian Neandertal from La Roche-à-Pierrot, supporting a pattern of changing mobility patterns among late Middle Paleolithic Neandertals on the eve of modern human dispersals into Europe.


Assuntos
DNA Mitocondrial/genética , Fêmur/anatomia & histologia , Fósseis , Hominidae/anatomia & histologia , Animais , Sequência de Bases , Radioisótopos de Carbono , França , Hominidae/genética , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA
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