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1.
Radiocarbon and U-series methods (230Th/U and 231Pa/235U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.  相似文献   

2.
Wezmeh Cave is located on the northeastern edge of the Islamabad plain, a high intermontane valley in the western‐central Zagros. In 1999 a disturbed but large faunal assemblage was recovered from this site. The abundant and extremely diverse faunal spectra present at Wezmeh Cave has highlighted the importance of this assemblage. Carnivore remains constitute the bulk of the assemblage; red fox (Vulpes vulpes) has the highest number of identified specimens followed by spotted hyena (Crocuta crocuta), brown bear (Ursus arctos), wolf (Canis lupus), felids (lion, leopard, lynx/caracal and wildcat), mustelids (badger, polecat, marten) and viverrids (mongoose). Artiodactyls (bovid, cervid, suid), equids, rhinoceros (Dicerorhinus sp.) and small animals (Cape hare, porcupine, tortoise, snake, birds) are also present. According to U‐series dating, the site was occupied from around 70 ka BP through to sub‐recent periods by carnivores. Amongst this rich assemblage, a human fossil tooth was also found and dated by non‐invasive spectrometry gamma dating to 20–25 ka BP. A preliminary zooarchaeological and taphonomic study shows that Wezmeh Cave was used by multiple carnivore species, a unique phenomenon in the Zagros Mountains in particular and southwest Asia in general. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

3.
Over a period of some 100 years it has gradually been accepted that the human skeletal remains found in the late nineteenth century in ancient gravels at Galley Hill, Kent are not those of early man, but are of much more recent date. This conclusion was finally verified by means of relative (N, F) and absolute (14C) dating. Here we present the results of further analysis of the remains from Galley Hill for their uranium content by a method having general application to the relative dating of fossil human and other mammalian bone.  相似文献   

4.
We report the results of a test excavation of deposits in a limestone cave sub-chamber located beneath the main chamber of Liang Bua, Flores, Indonesia; the discovery site of the small hominin species, Homo floresiensis. Well-preserved remains of extinct Pleistocene fauna and stone artefacts have previously been identified on the surface of a sediment cone within the sub-chamber. Our excavation of the deposits, at the base of the sediment cone in the sub-chamber (to 130 cm depth) yielded only a few fragmentary bones of extant fauna. Uranium/Thorium (U-series or U/Th) dating of soda straw stalactites excavated from 20 to 130 cm in depth demonstrates that the excavated sediments were deposited during the Holocene. Red Thermoluminescence (TL) dating of the sediments at the base of the excavation (130 cm depth) indicates these sediments were last exposed to sunlight at 84 ± 15 ka (thousand years), similar to red TL ages of cave sediments from the main chamber. Together, these results indicate that the surface faunal remains, which are morphologically analogous to Pleistocene finds from the main chamber excavations, were transported to the sub-chamber relatively recently from the main chamber of Liang Bua and probably originated from conglomerate deposits at the rear of the cave and from deposits around the front entrance. There is no evidence for hominin occupation of the sub-chamber, instead it seems to have acted as a sink for cultural materials and fossil remains transported from the surface via sinkholes. Despite the small number of finds from the test excavation, it is possible that more extensive excavations may yield additional transported cultural and faunal evidence at greater depths.  相似文献   

5.
The water vole, genus Arvicola, is characterised by a broad geographic distribution throughout Europe and is widespread during the late Middle and Upper Pleistocene. This genus is used as a major biostratigraphic tool within the Quaternary. Specific determinations using the Schmelzband-Differenzierung-Quotient or SDQ have identified many chronospecies within the fossil species Arvicola cantiana (Hinton, 1910). As SDQ calculation remains limited, this study reappraises the Arvicola genus in terms of morphodiversity and morphospace using outline analysis which takes into account the tooth as a whole. Outline analysis suggests that one single species of Arvicola, A. cantiana, was present during the Pleistocene. This species shows great variability with no trends or patterns in morphospace. Thus, these results call into question the reliability of SDQ for specific determinations and throw doubt on the biochronological framework based on Arvicola.  相似文献   

6.
ABSTRACT

Located on the edge of Australia's North West continental shelf, Barrow Island is uniquely located to address a number of research questions, such as the antiquity and changing nature of Indigenous occupation, including shifting uses of regional economic resources in response to post-glacial sea-level rise. These questions are addressed from a range of archaeological, zooarchaeological, and geoarchaeological disciplines. Although only preliminary, results to date indicate the presence of marine resources dating to before sea-level stabilization (~ 7.5 ka) that contain both dietary and utilitarian species, including high-ranked species such as sea turtle. The marine assemblages reflect a variety of habitats and substrates with a 17,000-year record for the presence of a former tidal marsh or estuary. We also note recently obtained 14C and OSL dates that extend the dietary marine faunas and initial occupation to well before 41 ka. This demonstrates that consumption of coastal resources began prior to the Holocene, when we begin to observe more widespread evidence of marine resource exploitation in the broader Canarvon Bioregion of northwest Australia. This evidence supports arguments for further research to directly test both the productivity of, and human reliance on, marine habitats from initial occupation.  相似文献   

7.
This study focuses on the analysis of the structural and textural features of the colluvial (deluvial) deposits in the Suwałki Lake District (NE Poland) and their absolute age. The colluvium has a thickness of up to 150 cm. The dates of the peat under colluvium or lowermost fossil humus-rich horizons point to the ages from 5405±80 BP to 480 BP. Deposition of material at the footslope is a result of a denudation triggered by human action (surface water erosion and tillage erosion) and usually corresponds with the settlement stages. The 14C dating of deposited sediment sometimes indicated to older dates of colluvium then the archaeological evidence available for examined sites. Locally, the overlying fossil humic horizon was older then the lowermost one. The textural features of the colluvial deposits such as: the content of fine fraction, weak sorting and relationship between the mean grain-size (Mz) and the sorting index (σ1) were used to recognize sediment redeposited from the upper part of the slope. Basing on the mineral composition and electrical conductivity of fossil humus horizon it is possible to say whether the soil was degraded or aggraded. These features of the humus-rich horizons occurring between colluvial sediments can be used to explain discrepancy between the radiocarbon dating and archaeological evidence.  相似文献   

8.
We describe a three dimensional preserved right tarsometatarsus, representing the first fossil crow from the well-known Early Pleistocene Nihewan paleolithic sites in North China. The new specimen is distinguished from other known species of the genus Corvus by the combined morphological features, especially the peculiar hypotarsus. The phylogenetic significance of the arrangement of canals at the proximal hypotarsus in passerines is discussed. Although the fossil was too incomplete to warrant the erection of a new species of Corvus, it nonetheless increases the taxonomical diversity of the Nihewan fauna and improves our knowledge on Pleistocene birds in China. Finally the paleoenvironment of the Nihewan sites are discussed in terms of its faunal composition.  相似文献   

9.
In this study, we propose a method based on life tables currently used in population dynamics and ecology to compare the mortality curves of Equidae from anthropic and carnivore fossil assemblages with those from modern populations. The combined analysis of frequency (fx) with various ecological parameters such as mortality rate (qx), survival rate (lx), fecundity rate (mx), and killing factor (kx), established for each age class, allows us to characterize the stability of fossil populations. These ecological parameters, developed in demography, correspond to many curves and constitute a complementary approach to interpret the two main mortality models, attritional and catastrophic, often evoked in zooarchaeology. The age structures of fossil horses from the anthropic sites of Bau de l'Aubesier (Vaucluse, France) and Combe-Grenal (Dordogne, France) and the hyena den of Fouvent (Haute-Saône, France) are compared to typical catastrophic modern populations of Equidae from the National Park of Akagera (Rwanda). We also used data collected by the Bureau of Land Management for present day feral horses from Pryor Mountain (Montana, USA) which constitutes a reliable referential of a stable living population. The characterization of age structures in those different contexts is discussed as well as the impact of Neanderthals and hyenas on fossil assemblages.  相似文献   

10.
As is widely recognised, fossil florules are difficult to correlate because they appear to have been more controlled by environmental and ecological factors than uniform changes which reflect the passage of geological time. Here I present a worked example of a generally applicable approach to this problem in dating and mapping fossil plant associations.

Floral associations are best described and named by the classical methods of phytosociology. The three dimensional shape of an association in rocks and its palaeoecology can then be critically assessed. For example, during Middle Triassic time the following plant associations would have been encountered on a traverse from the coast to several hundred kilometres inland from the Pacific margin of Gondwanaland: Pachydermophylletum (mangrove scrub), Linguifolietum (coastal swamp woodland), Dicroidietum odontopteroidium (floodplain forest), Phoenicopsetum (levee bank scrub), Dicroidietum odontopteroidium xylopterosum (xerophytic woodland) and Johnstonietum (mallee-like woodland).

The fourth dimension of fossil plant associations (time) is best assessed from the evolution of a prominent group of plants. In conjunction with the ranges of other plant megafossils, evolutionary changes can be used to define Oppel-zones. For the Late Permian to Early Jurassic of eastern Australasia, I have used the evolution of Dicroidium and leaves of related pteridosperm plants together with other species of restricted stratigraphic range or prominent in the definition of the fossil plant associations. From this evidence four Oppel-zones can be recognised. ‘Thinnfeldia’ callipteroides Oppel-zone (Chhidruan to Smithian, 250–230 × 106 years), Dicroidium zuberi Oppel-zone (Smithian to Middle Anisian, 230–220 × 106 years), D. odontopteroides Oppel-zone (Late Anisian to Ladinian, 220–210 × 106 years) and Yabeiella Oppel-zone (Carnian to Rhaetian, 210–200 × 106 years.

In a complete revision of the pteridosperm form-genera Dicroidium, Johnstonia and Xylopteris, a large number of new combinations and the following new taxa are proposed; Dicroidium gouldii sp. nov., D. odontopteroides var. argenteum var. nov., D. odontopteroides var. moltenense var. nov., D. radiatum sp. nov., D. townrovii sp. nov. and Johnstonia coriacea var. obesa var. nov.  相似文献   

11.
This study aimed to further test the method, reported by St Pierre et al. (2009), to develop robust chronologies of deposits in limestone caves through U/Th (Uranium/Thorium or U-Series) dating of soda straw stalactites. The chronology of fossil bearing deposits at Blanche Cave was further constrained with thermal ionisation mass spectrometry (TIMS) U/Th dating of 17 additional soda straw stalactite samples, and results were compared to recalibrated 14C ages of charcoal. The results support the assertion that soda straw stalactites can provide ages close to the time of sediment deposition and may be used as reliable chronological markers, particularly for periods reaching or beyond the radiocarbon dating limit. The application of an enhanced cleaning technique facilitated the reduction of detrital Th in samples, significantly increasing age accuracy and precision. Additionally U/Th age accuracy and precision was increased through the application of site-specific measured U/Th ratios to correct for the detrital 230Th component in samples.  相似文献   

12.
Two Agathis species that are endemic to New Caledonia, A. moorei and A. ovata, produce coarsely granulate inaperturate pollen that resembles pollen of the Wollemi Pine (Wollemi nobilis). For this reason, these Agathis species are potential nearest living relatives of the fossil species Dilwynites granulatus, whose stratigraphic distribution has been used to establish a fossil record for Wollemia.  相似文献   

13.
Traditionally, the systematics of the Seymour Island fossil penguins has been based on Wiman's groups defined by the robustness and size of isolated postcranial bones. However, current evaluations of fossil penguins necessitate that new species be established when the specimens include at least a tarsometatarsus or in some cases a humerus. Accordingly, neither of the two species reviewed herein (Orthopteryx gigas and Ichtyopteryx gracilis) are represented by remains sufficiently complete to validate a new taxon. Orthopteryx gigas is based on an isolated synsacrum lacking diagnostic characters. Ichtyopteryx gracilis is based on a tarsometatarsus but with insufficient preservational quality to justify discrimination of the species. For these reasons both Orthopteryx gigas and Ichtyopteryx gracilis should be considered nomen dubia.  相似文献   

14.
Examples of early astogeny in the species Carinatocella harmeri (Stach), Costaticella hastata (Busk) and Claviporella aurita (Busk) are discussed. The primary zoid differs in each species and if found fossil, only in C. hastata could this zoid be recognised as a bryozoan fragment. Analogous development in other Bryozoa is discussed.  相似文献   

15.
Leaves assignable to Nothofagus from two fossil deposits in Tasmania represent the first macrofossils of this genus from the Tertiary in southeastern Australia. One fossil species, N. johnstonii, is closely related to the extant Australian species N. cunninghamii while the other fossil species, N. tasmanica, has very close affinites with the extant Australian species N. moorei. All four of these species are closely interrelated. The pollen type produced by the fossil species is unknown, since all three types are present in the microfloras. However, both N. cunninghamii and N. moorei produce N. menziesii-type pollen. The macrofossils confirm the conclusion from pollen studies that evolution in Nothofagus has occurred very slowly.  相似文献   

16.
Yang, G., Yao, Y.Z. & Ren, D., iFirst. Poljanka strigosa, a new species of Protopsyllidiidae (Hemiptera, Sternorrhyncha) from the Middle Jurassic of China. Alcheringa, 1–6. ISSN 0311-5518.

A new fossil species, Poljanka strigosa sp. nov., of the extinct family Protopsyllidiidae is described from the Middle Jurassic Jiulongshan Formation of Daohugou Village, Inner Mongolia, China. The new species is characterized by wings bearing long, stiff setae that are evident as stained impressions in the fine sedimentary rock. Comparison between Protopsyllidiidae and extant psylloids suggests that Protopsyllidiidae is probably closely related to extant psylloids.  相似文献   

17.
Plant residues recovered from prehistoric stone artifacts can be used to help explain tool function and plant use. At the Changning site in Qinghai Province, Northwest China, dating from 4000 yr BP, we examined starch granules extracted from three slate stone knives. A total of 153 starch grains were retrieved from three stone knives, from which we identified starches from legumes, the Triticeae tribe, foxtail millet (Setaria italica), broomcorn millet (Panicum miliaceum), roots and tubers. These results indicate that the stone knives may have been used for a variety of activities that included reaping grasses and food processing. The species of starch grains retrieved from the study sample reveal that diverse crops were cultivated at the Changning site 4000 years ago.  相似文献   

18.
Bones of an Upper Pleistocene Camelus have been found in the northwestern Negev, they are of particular interest because they are larger than those of all the Old World camel species since the Plio-Pleistocene, and they are very much larger than the few fossil camels already known from the Middle East. It is suggested that they represent the only C. thomasi yet identified outside Africa.  相似文献   

19.
Evidence is accumulating that the hominid cranium found in the Petralona cave in 1960 is associated with cave deposits of middle Pleistocene age. If this is so, the fossil is the most complete middle Pleistocene cranium yet discovered and provides important morphological, metrical and radiographic information on the possible evolutionary transition from Homo erectus to Homo sapiens. The classification of the specimen is discussed and it is suggested that a grade system within Homo spaiens should be erected. The Petralona fossil would be allocated to Homo sapiens grade 1 rather than to Homo erectus or to a subspecies of Homo sapiens.  相似文献   

20.
Evidence of human activity and hominin remains are very scarce inland on the Iberian Peninsula. This fact raises the issue of the scarcity of evidence that Paleolithic Homo sapiens occupied this area outside of the littoral margins (Atlantic, Cantabrian, and Mediterranean coasts). Here, we comparatively describe a human right adult navicular bone recovered in the Cueva de los Torrejones site, located in the village of Tamajón (Guadalajara, Spain). This fossil was preliminarily established as belonging to Homo cf. neanderthalensis, due to the late Pleistocene faunal association, mainly because of the presence of Crocuta crocuta and Panthera pardus. The metrical and morphological study of the navicular T93-S3.27 from Cueva de los Torrejones clearly differentiates it from Neandertals and their ancestors, the hominins from Sima de los Huesos, allowing for this fossil to be taxonomically assigned with confidence as H. sapiens. The navicular from the Cueva de los Torrejones is absolutely and relatively medio-laterally narrow with a low wedging index as those of fossil and modern H. sapiens, and clearly different of Neandertals. The increased discoveries and publications of new naviculars belonging to genus Homo, together with the findings of P. pardus and C. crocuta in more recent chronologies in the Iberian Peninsula, are compatible with this reevaluation. We propose a probable chronology for this fossil between 12 and 15 ka and ca. 25 ka, based on the biostratigraphy and the oldest presence of H. sapiens in the Iberian Peninsula. This work confirms the human presence within the Iberian Peninsula during the Upper Paleolithic and reopens the question of the peopling of the inner Peninsula during this period.  相似文献   

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