首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
《Comptes Rendus Palevol》2008,7(8):487-497
The Middle Miocene Muruyur Formation (ca 14.5 Ma), Tugen Hills, Kenya, has yielded a huge creodont and a variety of carnivores ranging in size from mongoose-sized viverrids and herpestids to lion-sized amphicyonids. The fauna partly fills what used to be a major gap in our knowledge of Neogene African carnivores, spanning the period between the better known Early Miocene assemblages of western Kenya and eastern Uganda, and the Late Miocene and Plio–Pleistocene faunas of East Africa. Present in the deposits are Megistotherium, two species of Hecubides, one species of Agnotherium, Herpestes, Vishnuictis, and one or two undetermined felids.  相似文献   

2.
SK 847 and StW 53 have often been cited as evidence for early Homo in South Africa. To examine whether midfacial morphology is in agreement with these attributions, we analyze Euclidean distances calculated from 3-D coordinates on the maxillae of SK 847 and StW 53, as well as Australopithecus africanus (Sts 5, Sts 71), Paranthropus robustus (SK 46, SK 48, SK 52, SK 83), early Homo (KNM-ER 1813, KNM-ER 1805, KNM-ER 3733, KNM-WT 15000), P. boisei (KNM-ER 406, KNM-WT 17000, KNM-WT 17400), Gorilla gorilla (n = 116), Homo sapiens (n = 342), Pan paniscus (n = 21) and P. troglodytes (n = 65). Multivariate analyses separate extant hominoids suggesting we have captured taxonomic affinity. With the exception of SK 847 and SK 52, South African fossils tend to cluster together. P. robustus differs substantially from East African robust megadonts. SK 847 and StW 53 resemble the East African Homo specimens that are the most australopith-like, such as KNM-WT 15000 and KNM-ER 1813. The resemblance between StW 53 and Homo is driven partly by similarities in maxillary size. When distances are scaled, StW 53 aligns with A. africanus, while SK 847 clusters primarily with early Homo.  相似文献   

3.
《Geobios》2014,47(5):325-334
The micromammal sequence of the Calatayud-Montalbán Basin in Northeast Central Spain is exceptional in terms of its faunal richness and dating accuracy. However, until now, several classical localities with ages close to the Middle to Late Miocene transition have never been directly tied to the Geomagnetic Polarity Time Scale. Here, we present an updated stratigraphic framework for the Daroca area, resulting in new and better-constrained ages for the micro- and macromammal-bearing sites of Toril, Carrilanga, and Pedregueras, and the macromammal site Los Andurriales. Toril is correlated to chron C5Ar.1r with an age of 12.7 Ma. Carrilanga and Los Andurriales are dated at 11.3 Ma, slightly older than the nearby sites Nombrevilla 9–10 (11.2 Ma). The fauna of these latter sites just pre-dates the entry of Hipparion, which is supposed to have its first appearance in Europe also at 11.2 Ma. The age of Pedregueras 2A is estimated at 10.6 Ma, constraining the local Zone H–I boundary and the first Iberian occurrence of Cricetulodon to 10.7 or 10.6 Ma. With an age of 10.4 Ma, the site of Pedregueras 2C is documenting the presence of very rare Murinae in Europe long (ca. half a million years) before their attainment of general dominance.  相似文献   

4.
The purpose of this study is to explore the main correlates of male height in 105 countries in Europe & overseas, Asia, North Africa and Oceania. Actual data on male height are compared with the average consumption of 28 protein sources (FAOSTAT, 1993–2009) and seven socioeconomic indicators (according to the World Bank, the CIA World Factbook and the United Nations). This comparison identified three fundamental types of diets based on rice, wheat and milk, respectively. The consumption of rice dominates in tropical Asia, where it is accompanied by very low total protein and energy intake, and one of the shortest statures in the world (∼162–168 cm). Wheat prevails in Muslim countries in North Africa and the Near East, which is where we also observe the highest plant protein consumption in the world and moderately tall statures that do not exceed 174 cm. In taller nations, the intake of protein and energy no longer fundamentally rises, but the consumption of plant proteins markedly decreases at the expense of animal proteins, especially those from dairy. Their highest consumption rates can be found in Northern and Central Europe, with the global peak of male height in the Netherlands (184 cm). In general, when only the complete data from 72 countries were considered, the consumption of protein from the five most correlated foods (r = 0.85) and the human development index (r = 0.84) are most strongly associated with tall statures. A notable finding is the low consumption of the most correlated proteins in Muslim oil superpowers and highly developed countries of East Asia, which could explain their lagging behind Europe in terms of physical stature.  相似文献   

5.
《Palaeoworld》2014,23(3-4):370-382
Two fossil leaves identified as Castanopsis presclerophylla n. sp. collected from a diatomite bed in the upper Pliocene (3.3–2.8 Ma) in Tengchong County, Yunnan Province, Southwest China, are characterized by elliptic laminar shapes with acuminate apex, convex base, simple trichome bases and cyclocytic stomata. The cuticles of extant leaves from six selected Castanopsis species that are similar to the Pliocene fossil leaves in laminar shape were examined in detail for the comparison. Based on the analysis of leaf architecture and cuticular characteristics, the present fossil leaves most closely resemble the extant leaves of Castanopsis sclerophylla (Lindl.) Schott., which prefers a subtropical climate. The published fossil records of Castanopsis also indicate that it was once widely distributed in North America, Europe and Asia before the Pliocene, and then rapidly retreated to the East and Southeast Asia as a result of the Pleistocene glaciation.  相似文献   

6.
The earliest known hominid Sahelanthropus tchadensis Brunet et al., 2002, nicknamed Toumaï, from the Late Miocene (7 Ma) of Chad, displays a unique combination of primitive and derived characters which clearly shows that it is probably temporally close to the common ancestor of chimpanzees and humans. The Late Miocene Hominids: Sahelanthropus (Chad), Orrorin (Kenya), Ardipithecus (Ethiopia) are probably the ancestral group of Australopithecins from which the genus Homo appears between 2 and 3 Ma and then for the first time widespread in Eurasia. So, Toumaï seven millions years old confirms in a spectacular way the prediction Charles Darwin made in 1871.  相似文献   

7.
Pleistocene rhinoceroses are poorly documented in Turkey where they have been reported only from the late early Pleistocene (1.3–1.1 Ma) travertine deposits of the Denizli Basin. In this work, new rhinoceros remains collected from this basin are assigned to a relatively large-sized Stephanorhinus hundsheimensis on the basis of their morphology and morphometry. The first Turkish record of this species is approximately coeval with the first appearance of Shundsheimensis in Europe, chronologically referred to the late early Pleistocene, ca. 1.2 Ma. During that time, Setruscus still survived in Iberian Peninsula, central Italy and Dacian Basin. The presence of two successive evolutionary morphs for Shundsheimensis during the Pleistocene is not confirmed.  相似文献   

8.
《Comptes Rendus Palevol》2013,12(3):165-171
The puma-like cat Puma pardoides (Owen, 1846) is reported from several Eurasian localities dated to the Late Pliocene–Early Pleistocene, but its Italian fossil record is really poor; in fact, the only possible occurrence comprises some fragmentary postcranial material from the Late Villafranchian locality of Pirro Nord (1.6–1.3 Ma). In the present paper, we describe an isolated left upper carnassial of a medium-sized felid belonging to the collection of fossil mammals from Montopoli (Tuscany, Italy), the type locality of the Middle Villafranchian Faunal Unit (∼2.6 Ma). All the morphological and morphometric characters of the tooth are consistent with an attribution to Puma pardoides (Owen, 1846), which comes out as the second felid species from Montopoli together with Acinonyx pardinensis (Croizet et Jobert, 1828) and is, possibly with the specimens from Perrier-Étouaries, the earliest occurrence in western Europe.  相似文献   

9.
Despite the fact that genome size should be constant at species level, many reports of intraspecific variations exist. Thus, we carried out an analysis to determine the possible existence of nuclear DNA content variation in European black pine (Pinus nigra s.l.), a good model for such a study given its karyological uniformity, morphological polymorphism, broad geographical distribution, ecological plasticity and taxonomic heterogeneity. The panel comprised 20 populations across the natural range of P. nigra from Europe, Northwest Africa and Asia Minor including five subspecies: subsp. nigra, salzmanni, dalmatica, pallasiana and mauretanica. Mean 1C DNA content of the species was 23.62 pg (±0.209) assessed by flow cytometry. This converts to 23.1 G base pairs. The coefficients of variation within and between populations did not exceed 2.6%. Although we had already reported the existence of significant differences for three Black pine populations in our previous work on five Pinus spp. [Bogunic, F., Muratovic, E., Brown, S.C., Siljak-Yakovlev, S., 2003. Genome size of five Pinus from Balkan region. Plant Cell Rep. 22, 59–63], intraspecific variation was not confirmed in the present study dealing with many more populations. Subspecific divisions of Black pine were characterised with following mean values: subsp. pallasiana—23.80 pg, dalmatica—23.79 pg, nigra—23.65 pg, salzmanni—23.55 pg, and mauretanica—23.24 pg. A positive relationship between genome size and longitude was observed (r = 0.44, p < 0.05). We conclude that the diversification of populations of P. nigra has occurred without significant genome size changes throughout its wide geographical range from ecologically contrasting habitats. A clinal mode of genome size variation is present, in line with hypothesis of P. nigra spreading from south-western Asia towards European habitats.  相似文献   

10.
IntroductionThe epidemiology of chronic myeloid leukemia (CML) in low and middle income countries is limited. As a result, we analyzed a contemporary cohort of patients from low and middle income countries treated with Imatinib through The Glivec® International Patient Assistance Program (GIPAP).MethodsGeneralized estimating equations (GEE) and Kaplan–Meier estimation were utilized to test for regional variations in age at diagnosis and overall survival among 33,985 patients from 94 countries.ResultsPatients participated from Asia (79.2%), Africa (9.4%), Latin America (8.7%) and Southern/Eastern Europe (2.5%). Sixty-one (61.2%) percent were male. Mean age at diagnosis was 38.5 years (9.4% <20 years and only 4.7% ≥65 years). Using GEE, Asians were youngest (38.3 years), followed by Africans (39.5 years), Southern/Eastern Europeans (41.1 years) and Latin Americans (41.3 years; p < 0.0001). Diagnoses were predominately in chronic stage (78.3%). In 2002, 85.2% of patients had a delay in treatment >1 year; decreasing to 15.5% in 2010 (p < 0.0001). The 3-year overall survival probability was 89.4% (95% CI, 88.9–89.9). In multivariate analysis, risk of death increased among patients 65 years or older at diagnosis (p < 0.0001), time from diagnosis to treatment >1-year (p < 0.0001), diagnoses in the accelerated or blast crisis (p < 0.0001), initial dose of Imatinib >400 mg (p < 0.0001) and among Latin Americans and Africans (p < 0.0001).ConclusionThe GIPAP cohort is the largest series of patients with CML described from low and middle income countries. Differences in age at diagnosis and overall survival exist within and between regions. Additional epidemiological studies should be conducted to assess for possible environmental factors associated with the earlier age at onset.  相似文献   

11.
12.
The astronomically tuned marls of the Monte Gibliscemi section, Sicily, constitute an archive to trace the late Miocene palaeoenvironmental conditions (~ 9.7–7.0 Ma) in North Africa. Here we have utilised carbonate content and Al-normalised geochemical proxies to trace changes in terrigenous source area and bottom-water ventilation. The terrigenous input into the section is dominated by North African river systems draining into the Eastern Mediterranean. The proxy parameters indicate that the palaeoenvironmental conditions in North Africa were humid from 9.5 Ma onward with high fluvial input to the Mediterranean. Increases in the Si/Al and Mg/Al ratios occurred from 8.4 to 8.2 Ma and from 8.05 to 7.75 Ma, with maximum values similar to those of Messinian diatomites. These peaks indicate conditions of enhanced biosiliceous productivity and the presence of authigenic clay formation. Sluggish water circulation in the Mediterranean during those times is inferred from the Mn/Al and V/Al behaviour. Late Miocene changes of the Betic (southern Spain) and Rifian (Morocco) Mediterranean–Atlantic gateways are interpreted as the driving force for the changes in water circulation and the transgression associated with the opening of the Rifian corridor is interpreted to occur at 7.8 Ma.  相似文献   

13.
The Valdavara-1 cave, located in the westernmost part of the Iberian Peninsula, is an archaeological site that has been excavated since 2007. At least two main sedimentary units have been identified: an upper one, 30 cm-thick, that has yielded many fragments of ceramic characteristic of the Recent Prehistory (with a radiocarbon age of 4.490 ± 40 years BP), and a lower one, 90 cm-thick, separated from the upper one by an erosive discontinuity and late Pleistocene in age (radiocarbon ages between 13.770 ± 70 and 15.120 ± 70 years BP). The small-vertebrate assemblages recovered from the sieving-washing of all the sediment from the excavation campaigns include a total of at least 34 taxa (six amphibians, nine squamate reptiles, five insectivores, two chiropterans and 12 rodents). The materials from this locality constitutes the first mention in northwestern Spain for Microtus (Iberomys) cabrerae and Micromys minutus, currently absent from this area, as well as the first mention in the fossil record for Chioglossa lusitanica, Discoglossus galganoi and Chalcides striatus. In both layers, such small-vertebrate associations suggest a patchy landscape dominated by humid meadows and woodland areas, with the existence of water areas in the vicinity of the cave. The climate shows a more continental pattern during the late Pleistocene, as evidenced by the presence of Microtus arvalis, Sorex minutus and Rana temporaria, and was milder during the Recent Prehistory, with the occurrence of typically Mediterranean taxa such as Crocidura russula, Chioglossa lusitanica, Discoglossus galganoi, Rana iberica, Chalcides striatus and Timon lepidus. The amphibian and squamate associations suggest that the climate change recorded at the Valdavara-1 cave between the latest Pleistocene and Holocene levels may correspond to a difference of 0.8 °C in terms of mean annual temperature, although the difference is 2.8 °C for the mean temperature of the coldest month.  相似文献   

14.
Despite uncontested evidence for fossils belonging to the early hominin genus Australopithecus in East Africa from at least 4.2 million years ago (Ma), and from Chad by 3.5 Ma, thus far there has been no convincing evidence of Australopithecus, Paranthropus or early Homo from the western (Albertine) branch of the Rift Valley. Here we report the discovery of an isolated upper molar (#Ish25) from the Western Rift Valley site of Ishango in Central Africa in a derived context, overlying beds dated to between ca. 2.6 to 2.0 Ma. We used µCT imaging to compare its external and internal macro-morphology to upper molars of australopiths, and fossil and recent Homo. We show that the size and shape of the enamel-dentine junction (EDJ) surface discriminate between Plio-Pleistocene and post-Lower Pleistocene hominins, and that the Ishango molar clusters with australopiths and early Homo from East and southern Africa. A reassessment of the archaeological context of the specimen is consistent with the morphological evidence and suggest that early hominins were occupying this region by at least 2 Ma.  相似文献   

15.
Peat molecular chemistry reflects a combination of plant input and decomposition. Both vegetation community and the degree of decomposition of plant remains are highly dependent on depth and fluctuation of the water table and thus peat organic matter (OM) chemistry reflects past hydrological conditions. Changes in hydrology according to the OM composition (by pyrolysis-gas chromatography/mass spectrometry, pyrolysis-GC/MS) in a high-resolution sampled monolith of an 8000 years old peat deposit are presented. Analysis of 18 modern vegetation species resulted in molecular markers for Erica spp., Deschampsia flexuosa, Juncus bulbosus and Carex binervis, in addition to more general markers which enabled differentiation between woody, grass and moss vegetation. Factor analysis of 106 pyrolysis products quantified for all peat samples enabled identification of mineral (Factor 1) and hydrological (Factor 2) conditions of the bog. Depth profiles of vegetation markers showed good agreement with those of the scores of both factors and enabled the identification of 14 relatively wet periods, dating to 1430–1865 AD, 930–1045 AD, 640 AD, 270–385 AD, 190–215 AD, 135 AD, 45 BC–15 AD, 260–140 BC, 640–440 BC, 1055–960 BC, 1505–1260 BC, 2300 BC, 4190–2945 BC and 5700–5205 BC, which show excellent agreement with other palaeoclimatic studies in Europe. The results emphasize the importance of high-resolution sampling, in combination with the use of multiple vegetation markers and other peat OM characteristics for a proper interpretation of a peat record.  相似文献   

16.
This study investigated 37 diverse sainfoin (Onobrychis viciifolia Scop.) accessions from the EU ‘HealthyHay’ germplasm collection for proanthocyanidin (PA) content and composition. Accessions displayed a wide range of differences: PA contents varied from 0.57 to 2.80 g/100 g sainfoin; the mean degree of polymerisation from 12 to 84; the proportion of prodelphinidin tannins from 53% to 95%, and the proportion of trans-flavanol units from 12% to 34%. A positive correlation was found between PA contents (thiolytic versus acid–butanol degradation; P < 0.001; R2 = 0.49). A negative correlation existed between PA content (thiolysis) and mDP (P < 0.05; R2 = −0.30), which suggested that accessions with high PA contents had smaller PA polymers. Cluster analysis revealed that European accessions clustered into two main groups: Western Europe and Eastern Europe/Asia. In addition, accessions from USA, Canada and Armenia tended to cluster together. Overall, there was broad agreement between tannin clusters and clusters that were based on morphological and agronomic characteristics.  相似文献   

17.
《L'Anthropologie》2022,126(1):102994
Early Paleolithic sites (Oldowan and Acheulian) in the European part of Russia are concentrated in the southern part of the Russian plain, in the piedmont of the Caucasus and in the North Caucasus, south from 50 N latitude. The Taman Paleolithic complex (sites of Bogatyri/Sinyaya Balka, Rodniki 1 and 2, Kermek; and localities of Tsymbal, Lisy and Peresyp), Akushin Paleolithic complex in Central Dagestan (sites of Aynikab 1, Mukhkay 1 and 2) and complex of sites in Maritime Dagestan (sites of Rubas 1, Darvagchay 1, Darvagchay-Zaliv 1 and 4) are discovered and studied. The initial human settlement of southern Russia began about 2 Ma and went through the Caucasian isthmus along the western shore of the Caspian Sea. The most ancient Homo of the first wave of settlement from the African ancestral homeland was able to reach the Caucasus and the southern part of the Russian plain by 2 Ma, as confirmed by the Liventsovka locality in the city of Rostov-on-Don. The Acheulian is represented by stratified sites of the Early Acheulian on the territory of Dagestan. At present, it can be argued that the territory of southern Russia was part of the area of initial human settlement from Africa. It is more difficult to estimate the time and ways of the initial human settlement of Northern Asia. The few sites attributed to the Lower Paleolithic are, for the most part, geologically unconnected or are questioned as to the authenticity of the artifacts. The only clearly stratified Middle Pleistocene site, Karama in the Altai, delivered a pebble tool industry. In addition, the finds of bifaces in Tuva, near the Mongolian border mark the northern limit of the distribution of the Acheulian in Asia.  相似文献   

18.
The first trees in New York were Middle Devonian (earliest Givetian) cladoxyls (?Duisbergia and Wattieza), with shallow-rooted manoxylic trunks. Cladoxyl trees in New York thus postdate their latest Emsian evolution in Spitzbergen. Progymnosperm trees (?Svalbardia and Callixylon–Archaeopteris) appeared in New York later (mid-Givetian) than progymnosperm trees from Spitzbergen (early Givetian). Associated paleosols are evidence that Wattieza formed intertidal to estuarine mangal and Callixylon formed dry riparian woodland. Also from paleosols comes evidence that Wattieza and Callixylon required about 350 mm more mean annual precipitation than plants of equivalent stature today, that Wattieza tolerated mean annual temperature 7 °C less than current limits of mangal (20 °C), and Callixylon could tolerate temperatures 14 °C less than modern mangal. Devonian mangal and riparian woodland spread into New York from wetter regions elsewhere during transient paleoclimatic spikes of very high CO2 (3923 ± 238 ppmv), and subhumid (mean annual precipitation 730 ± 147 mm) conditions, which were more likely extrinsic atmospheric perturbations rather than consequences of tree evolution. For most of the Middle Devonian CO2 was lower (2263 ± 238 ppmv), and paleoclimate in New York was semiarid (mean annual precipitation 484 ± 147 mm). Such transient perturbations and immigration events may explain the 40 million year gap between the late Emsian (400 Ma) evolution of trees and Famennian (360 Ma) CO2 drawdown and expansion of ice caps.  相似文献   

19.
《Comptes Rendus Palevol》2008,7(8):557-569
New observations on the Late Miocene and Earliest Pliocene mustelids from the Middle Awash of Ethiopia are presented. The Middle Awash study area samples the last six million years of African vertebrate evolutionary history. Its Latest Miocene (Asa Koma Member of the Adu-Asa Formation, 5.54–5.77 Ma) and Earliest Pliocene (Kuseralee and Gawto Members of the Sagantole Formation, 5.2 and 4.85 Ma, respectively) deposits sample a number of large and small carnivore taxa among which mustelids are numerically abundant. Among the known Late Miocene and Early Pliocene mustelid genera, the Middle Awash Late Miocene documents the earliest Mellivora in eastern Africa and its likely first appearance in Africa, a new species of Plesiogulo, and a species of Vishnuonyx. The latter possibly represents the last appearance of this genus in Africa. Torolutra ougandensis is known from both the Late Miocene and Early Pliocene deposits of the Middle Awash. The genus Sivaonyx is represented by at least two species: S. ekecaman and S. aff. S. soriae. Most of the lutrine genera documented in the Middle Awash Late Miocene/Early Pliocene are also documented in contemporaneous sites of eastern Africa. The new observations presented here show that mustelids were more diverse in the Middle Awash Late Miocene and Early Pliocene than previously documented.  相似文献   

20.
《Comptes Rendus Palevol》2016,15(7):825-836
The Latest Miocene succession of the Baccinello-Cinigiano Basin in southern Tuscany (Italy) recorded a faunal turnover documenting the extinction of an older, insular, endemic faunal complex characterised by the extinct ape Oreopithecus bambolii and the setting of a new, continental, European faunal complex including the colobine monkey Mesopithecus. A similar turnover pattern (Late Miocene ape/Latest Miocene Cercopithecidae) is generally observed in Late Miocene continental successions of Eurasia, from Spain to central Europe, Southwest Europe, the near East, and Southwest Asia. Abundant literature reports that the Late Miocene Eurasian hominoid primate distribution closely tracks the climatic/environmental changes occurring during the 12–9 Ma interval, until their extinction in western Europe. In the primate record, the dispersion of Cercopithecidae and the contraction of hominids is interpreted as an event depicting a pattern of “continentalisation” in the Old World. The sedimentary succession of the Baccinello-Cinigiano basin, one of the longest continuous vertebrate-bearing continental successions in the Neogene Italian record, contributes to the debate on this hypothesis. This paper provides an overview of the main characteristics of the sedimentary succession, the chronological constraints (biochronology, radiometric datings, magnetostratigraphy), and the palaeoenvironmental evolution as derived from palaeobiological approaches and from the study of stable carbon and oxygen isotope contents along the entire sedimentary succession. The 2 myr geological history of the Baccinello Cinigiano Basin, which documents the evolutionary history of Oreopithecus and associated faunas, does not have a direct relation with the event of the Messinian Salinity Crisis. The evolutionary history of Baccinello-Cinigiano Basin and its palaeontological record have been mainly driven by the regional tectonism and palaeogeographic changes that affected the northern Tyrrhenian regions in Late Miocene (Latest Tortonian–Messinian) times.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号