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1.
The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers ∼600 ka, but could not be occupied until ∼190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next ∼190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until ∼100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.  相似文献   

2.
This article reports on an example of early archaeobotanical evidence for beer-making in Iron Age South-Eastern France. An archaeological sample from a fifth century BC house at the site of Roquepertuse produced a concentration of carbonized barley (Hordeum vulgare) grains. The sample was taken from the floor of the dwelling, close to a hearth and an oven. The barley grains are predominantly sprouted and we argue that the assemblage represents the remains of deliberate malting. Malt was most likely related to beer-brewing. The neighboring oven could have been used to stop the germination process at the desired level by drying or roasting the grain. Beer-making evidence in Roquepertuse is discussed in the context of the consumption of alcoholic beverages in the Iron Age Western Mediterranean using archaeological and historical data.  相似文献   

3.
A human skeleton recovered from a Sicilian archaeological site and dating from the Hellenistic period (330–210 B.C. ) presents a pathological pattern suggesting a transition between ankylosing spondylitis and rheumatoid arthritis, providing evidence in support of the hypothesis that rheumatoid arthritis may have recently evolved out of ankylosing spondylitis.  相似文献   

4.
A human skeleton recovered from a Sicilian archaeological site and dating from the Hellenistic period (330-210 B.C.) presents a pathological pattern suggesting a transition between ankylosing spondylitis and rheumatoid arthritis, providing evidence in support of the hypothesis that rheumatoid arthritis may have recently evolved out of ankylosing spondylitis.  相似文献   

5.
Multiproxy analysis (pollen, diatom, charcoal) on a 6 m core from Lago Verde (Sierra de Los Tuxtlas), shows evidences of environmental changes and human impact on the evergreen rainforest on the tropical lowlands of eastern Mexico during the last ca. 2,800 years. Prehistoric human occupation is recorded since the late Formative throughout the middle Classic (250 b.c.–ca. a.d. 800) by the presence of maize pollen, a low abundance of tropical arboreal taxa and a high abundance of herbaceous pollen and charcoal particles. This occurred under a scenario of very low lake levels from which dry conditions are inferred based on the dominance of aerophilous and periphytic diatom taxa. After ca. a.d. 800 the site was abandoned and forest regeneration started, at the same time higher lake levels, an indication of more humid conditions, were established. In the absence of human disturbance, tropical forest regeneration was rapid (ca. 200 years). Fluctuations in pollen composition during times of low human population at the site are related to climate variability, with the highest tropical forest diversity and lake levels recorded during the Little Ice Age. Modern human impact is also recorded and compared with the prehistoric deforestation event. Comparison with palaeoecological records from Yucatan and the highlands of central Mexico offers a Mesoamerican perspective of climatic variability giving evidence that the late Formative and early to middle Classic demographic expansion occurred under a scenario of climates dryer than present, with the Postclassic characterized by moister conditions. The end of the Classic (ca. a.d. 800–1000) is identified as a period of rapid climate change which marks one of the most important cultural transitions in Mesoamerica.  相似文献   

6.
Headland and Bailey (1991) argued in Human Ecology that tropical forests could not support long-term human foraging in the absence of agriculture. Part of their thesis was based on the fact that supposedly isolated ‘forest’ foragers, such as the Wanniyalaeto (or Vedda) peoples of Sri Lanka, could be demonstrated to be enmeshed within historical trade networks and rely on crops as part of their overall subsistence. Yet, in the same volume and in the years that followed scholars have presented ethnographic and archaeological evidence, including from Sri Lanka, that counter this proposition, demonstrating the occupation and exploitation of tropical rainforest environments back to 38,000 years ago (ka) in this part of the world. However, archaeological and ethnohistorical research has yet to quantify the overall reliance of human foragers on tropical forest resources through time. Here, we report stable carbon and oxygen isotope data from historical Wanniyalaeto individuals from Sri Lanka, in full collaboration with the present-day members of this group, that suggest that while a number of individuals made use of agricultural resources in the recent past, others subsisted primarily on tropical forest resources as late as the 1800s.  相似文献   

7.
A multi-proxy analysis of microfossils from sedimentary records, together with evidence from historical and archaeological data, has provided evidence of vegetation dynamics and human environment interactions in western Uganda for the last 1000 years. Pollen, fungal spores and phytoliths extracted from sediment cores obtained from a papyrus swamp at Munsa archaeological site indicate a relatively wet and forested environment in western Uganda prior to ca 1000 yr bp (cal 977–1159 ad ). A subsequent decline in forest vegetation occurred from ca 920 yr bp (cal 1027–1207 ad ). However, the deforestation period occurred during a wet period as registered in the River Nile water records, suggesting a human induced deforestation at Munsa rather than reduced precipitation. Increased numbers of herbivores, presumably domesticated cattle, postdeforestation are evidenced by the presence of dung fungal spores and broad accord with the archaeological evidence for initial occupation of the site at Munsa and the establishment of a mixed economy based on crops, cattle and iron working between 1000 and 1200 ad . From ca 200 yr bp (cal 1647–1952 ad ), forest recovery occurred at Munsa site and appears to reflect abandonment of the site, as suggested by archaeological evidence, possibly following a period of prolonged drought and famine between 1600 and 1800 ad , as recounted in the oral rich traditions of western Uganda and also reflected by low water levels of River Nile.  相似文献   

8.
The cultural landscape development of a farming community in western Norway was investigated through pollen analyses from a lake and a peat/soil profile. The pollen record from the lake indicates that there was a decrease in arboreal pollen (AP) by the end of the Mesolithic period (ca. 4200 cal b.c.), and that a substantial forest clearance occurred during the Bronze Age (ca. 1500 cal b.c.). The latter, together with grazing indicators and cereals, suggests a widespread establishment of farming. At the beginning of the Roman Iron Age there is an increase in heath communities. The pollen diagram from the peat/soil profile shows the forest clearance in the Bronze Age more clearly than the lake profile. This local pollen diagram is compared with modern pollen samples from mown and grazed localities in western Norway. Both analogue matching and ordination (PCA) indicate that the site was characterised by pastures and cereal fields from the Late Bronze Age to the Late Iron Age. An expansion of cereal cultivation took place during the Pre-Roman Iron Age, and an arable field was established at the site after ca. a.d. 800. This investigation illustrates the potential of selecting pollen sites reflecting different spatial scales, and complements the cultural history of the area as inferred from archaeological and historical records.  相似文献   

9.
For centuries Amazonia has held the Western scientific and popular imagination as a primordial forest, only minimally impacted by small, simple and dispersed groups that inhabit the region. Studies in historical ecology refute this view. Rather than pristine tropical forest, some areas are better viewed as constructed or 'domesticated' landscapes, dramatically altered by indigenous groups in the past. This paper reviews recent archaeological research in several areas along the Amazon River with evidence of large pre-European (ca 400-500 calendar years before the present) occupations and large-scale transformations of forest and wetland environments. Research from the southern margins of closed tropical forest, in the headwaters of the Xingu River, are highlighted as an example of constructed nature in the Amazon. In all cases, human influences dramatically altered the distribution, frequency and configurations of biological communities and ecological settings. Findings of historical change and cultural variability, including diverse small to medium-sized complex societies, have clear implications for questions of conservation and sustainability and, specifically, what constitutes 'hotspots' of bio-historical diversity in the Amazon region.  相似文献   

10.
中国长江流域有着丰富的林木资源, 包含极高水平的物种多样性、特有性和遗传多样性。根据考古证据, 在旧石器和新石器时代长江文明早期的孕育与发展中, 林木在食物、能源、工具、建筑和舟船中的应用起到了关键作用。现在, 长江流域和珠江流域逐渐成为国内木材供给的热点地区。面对木材供给总量不足和大径级木材结构性短缺问题, 长江流域林木资源将是未来国内木材安全的重要保障。这使得林木种质资源的保护更加迫切。针对长江流域林木种质资源保护存在的家底不清和保存体系不完善问题, 我们应尽快完成林木种质资源的全面调查和重要树种的多样性分析; 完善原地、异地和设施保存相结合的保存体系。  相似文献   

11.
Until now, Dicrocoelium sp. eggs have only been recorded from European and 1 North American archaeological sites. We present evidence for the first record of Dicrocoelium sp. from an African archaeological site. A paleoparasitological study was conducted on 7 coprolite samples from K2, a Late Iron Age site on the farm Greefswald, in the Northern Province of South Africa. Standard parasitological analysis revealed the presence of Dicrocoelium sp. and Trichuris sp. eggs. Today, the parasite does not occur in this region. Trichurid eggs are a relatively common find in paleoparasitological analysis. The presence of Dicrocoelium sp. provides new clues about the antiquity of this parasite, as well as aspects of ancient environment, climate, and interactions among humans, animals, and parasites.  相似文献   

12.
Two of the main hypotheses to explain the distribution and special characteristics of tropical heath forest are nutrient and water limitation. A study was undertaken to investigate both factors on two sites under tropical heath forest (Badas Forest Reserve) and mixed‐dipterocarp forest (Andulau Forest Reserve) in Brunei. Soil water potentials were monitored at depths of 20, 50, and 90 cm over wet and dry periods for five months at each site. The results showed the mixed‐dipterocarp forest site to be drier at 50 cm depth compared to the tropical heath forest site. There was no significant difference in water potentials between sites at 20 or 90 cm. Nutrient concentrations in the soil solution were monitored at the same depths over a seven‐month period at the same sites. A 12‐month litterfall study was also undertaken to monitor nutrient returns from the canopy at each site. The results of both studies suggest that the tropical heath forest site is poorer in nitrogen, but richer in calcium, than the mixed‐dipterocarp forest site. The results for phosphorus are less clear, but do not suggest that its limitation is a significant factor at the tropical heath forest site compared to the mixed‐dipterocarp forest site. Phosphorus and magnesium concentrations in the soil solution showed a strong positive correlation with sliding 30‐day rainfall totals at both sites.  相似文献   

13.
The Eastern Pygmies from Zaire and Western Pygmies from Cameroon, Congo, and the Central African Republic represent the two principal groups of African Pygmies. In the "recent divergence" hypothesis in which Western Pygmies are thought to be the result of hybridization between the ancestors of Eastern Pygmies and Bantu farmers who penetrated the equatorial belt and came into contact with Pygmies around 2-3 kiloyears ago. On the basis of recent archaeological research in the tropical rain forest, we propose a "pre-Bantu divergence" hypothesis, which posits the separation between the ancestors of Eastern and Western Pygmies earlier than 18 kiloyears ago. In order to test the two hypotheses, we analyzed the variation of the hypervariable region 1 of the mitochondrial DNA in the Mbenzele, Western Pygmies of the Central African Republic, and compared our results with those of previous mtDNA and Y chromosome studies. Distribution, sequence variation, and age of haplogroups along with genetic distances among populations, estimates of divergence times, and simulations based on the coalescent approach were found to be congruent with the pre-Bantu divergence but failed to support the recent divergence hypothesis.  相似文献   

14.
The archaeological deposits at Mumba rockshelter, northern Tanzania, have been excavated for more than 70 years, starting with Margit and Ludwig Köhl-Larsen in the 1930s. The assemblages of Middle Stone Age (MSA) and Later Stone Age (LSA) artefacts collected from this site constitute the type sequences for these cultural phases in East Africa. Despite its archaeological importance, however, the chronology of the site is poorly constrained, despite the application since the 1980s of several dating methods (radiocarbon, uranium-series and amino acid racemisation) to a variety of materials recovered from the deposits. Here, we review these previous chronologies for Mumba and report new ages obtained from optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) measurements on single grains of quartz and multi-grain aliquots of potassium (K) feldspar from the MSA and LSA deposits. Measurements of single grains of quartz allowed the rejection of unrepresentative grains and the application of appropriate statistical models to obtain the most reliable age estimates, while measurements of K-feldspars allowed the chronology to be extended to older deposits. The seven quartz ages and four K-feldspar ages provide improved temporal constraints on the archaeological sequence at Mumba. The deposits associated with the latest Kisele Industry (Bed VI-A) and the earliest Mumba Industry (Bed V) are dated to 63.4 ± 5.7 and 56.9 ± 4.8 ka (thousands of years ago), respectively, thus constraining the time of transition between these two archaeological phases to ∼60 ka. An age of 49.1 ± 4.3 ka has been obtained for the latest deposits associated with the Mumba Industry, which show no evidence for post-depositional mixing and contain ostrich eggshell (OES) beads and abundant microlithics. The Nasera Industry deposits (Bed III) contain large quantities of OES beads and date to 36.8 ± 3.4 ka. We compare the luminescence ages with the previous chronologies for Mumba, and briefly discuss how the revised chronology fits in the context of existing archaeological records and palaeoclimatic reconstructions for East Africa.  相似文献   

15.
Basic knowledge of the relationships between tree growth and environmental variables is crucial for understanding forest dynamics and predicting vegetation responses to climate variations. Trees growing in tropical areas with a clear seasonality in rainfall often form annual growth rings. In the understory, however, tree growth is supposed to be mainly affected by interference for access to light and other resources. In the semi-deciduous Mayombe forest of the Democratic Republic of Congo, the evergreen species Aidia ochroleuca, Corynanthe paniculata and Xylopia wilwerthii dominate the understory. We studied their wood to determine whether they form annual growth rings in response to changing climate conditions. Distinct growth rings were proved to be annual and triggered by a common external factor for the three species. Species-specific site chronologies were thus constructed from the cross-dated individual growth-ring series. Correlation analysis with climatic variables revealed that annual radial stem growth is positively related to precipitation during the rainy season but at different months. The growth was found to associate with precipitation during the early rainy season for Aidia but at the end of the rainy season for Corynanthe and Xylopia. Our results suggest that a dendrochronological approach allows the understanding of climate–growth relationships in tropical forests, not only for canopy trees but also for evergreen understory species and thus arguably for the whole tree community. Global climate change influences climatic seasonality in tropical forest areas, which is likely to result in differential responses across species with a possible effect on forest composition over time.  相似文献   

16.
The archaeological site of Sovjan is located at the edge of lake Maliq. It was occupied from the early Bronze Age to the early Iron Age. Pollen data from a short sequence of peat deposits dated between 4255±50 and 2420±45 uncal B.P. and charcoal, seeds and wood from archaeological deposits have provided new information on human activities in the region. They are discussed in the general frame of agricultural developments in the Balkans. Regional environment (regarding vegetation and hydrology) and climate are also discussed. Received June 15, 2000 / Accepted March 8, 2001  相似文献   

17.
The flux and composition of carbon (C) from land to rivers represents a critical component of the global C cycle as well as a powerful integrator of landscape‐level processes. In the Congo Basin, an expansive network of streams and rivers transport and cycle terrigenous C sourced from the largest swathe of pristine tropical forest on Earth. Increasing rates of deforestation and conversion to agriculture in the Basin are altering the current regime of terrestrial‐to‐aquatic biogeochemical cycling of C. To investigate the role of deforestation on dissolved organic and inorganic C (DOC and DIC, respectively) biogeochemistry in the Congo Basin, six lowland streams that drain catchments of varying forest proportion (12%–77%) were sampled monthly for 1 year. Annual mean concentrations of DOC exhibited an asymptotic response to forest loss, while DIC concentrations increased continuously with forest loss. The isotopic signature of DIC became significantly more enriched with deforestation, indicating a shift in source and processes controlling DIC production. The composition of dissolved organic matter (DOM), as revealed by ultra‐high‐resolution mass spectrometry, indicated that deforested catchments export relatively more aliphatic and heteroatomic DOM sourced from microbial biomass in soils. The DOM compositional results imply that DOM from the deforested sites is more biolabile than DOM from the forest, consistent with the corresponding elevated stream CO2 concentrations. In short, forest loss results in significant and comprehensive shifts in the C biogeochemistry of the associated streams. It is apparent that land‐use conversion has the potential to dramatically affect the C cycle in the Congo Basin by reducing the downstream flux of stable, vascular‐plant derived DOC while increasing the transfer of biolabile soil C to the atmosphere.  相似文献   

18.
Age at death of a single skeletal individual or a group is essential information in archaeological, paleoanthropological, and forensic contexts. Dental remains are the most commonly used age indicators, but when the dentition is not available, or too few teeth are present for an accurate age assessment, other age indicators such as skeletal maturation must be used. Of particular utility in this regard is the fusion of the epiphyses of the infracranial skeleton. Here we present new aging standards based on the infracranial maturation of individuals from the known age and sex collection from Coimbra, Portugal. We scored infracranial epiphyseal fusion and spheno-occipital synchondrosis closure (64 loci of ossification in total) on 137 skeletons from individuals between 7 and 29 years old. We further discuss developmental differences between the sexes and similarities and differences between the Coimbra documented collection and other published aging standards.  相似文献   

19.
The tropical forests of the Congo Basin constitute biodiversity refuges that still hold large numbers of species, including endemic and endangered vertebrates. Along with several key species, the critically endangered western lowland gorilla (WLG) potentially contributes to forest dynamics through seed dispersal. Considering the extensive influence of timber harvesting on tropical forest ecosystems, the survival of gorilla populations in logged forests might prove critical for forest ecosystem conservation. We estimated WLG density, through a nest count survey, in a forest in southeast Gabon that has been logged for 25 years. Nesting behavior and habitat use were described and we applied generalized linear models to identify the factors that influence gorilla day and night habitat use. The estimated density of weaned gorillas, 1.5 gorillas km?2, is comparable with estimates from some protected areas and other sustainably managed sites within their range. Habitat type had the greatest influence on nest site distribution. We observed a preference for nesting in open terra firma forest, and open habitats in general, which supports the findings of previous studies. Habitat use during the day was strongly influenced by habitat type and human activities, and to a lesser degree by functional and non-functional roads, and rivers. Our results support the suggestion that logged forests are suitable habitats for WLG if hunting and poaching are controlled. We recommend collaborations between timber operators and scientists to improve the conservation potential of tropical forests and enhance the wildlife-management aspects of logging practices.  相似文献   

20.
The discovery of the Nuragic culture settlement of Sa Osa, Cabras-Oristano, Sardinia, has made it possible to investigate the domestication status of waterlogged uncharred grape pips that were recovered from three wells dating from the Middle and Late Bronze Age (ca. 1350–1150 bc). Applying the stepwise linear discriminant analysis method, a morphological comparison of archaeological seeds and modern wild and cultivated Sardinian grapes pips was performed to determine the similarities between them. The results showed that the archaeological seeds from the Middle Bronze Age have intermediate morphological traits between modern wild and cultivated grape pips from Sardinia. In contrast, the analyses performed on the archaeological seeds from the Late Bronze Age showed a high degree of similarity with the modern cultivars in Sardinia. These results provide the first evidence of primitive cultivated Vitis vinifera in Sardinia during the Late Bronze Age (1286–1115 cal bc, 2σ). This evidence may support the hypothesis that Sardinia could have been a secondary domestication centre of the grapevine, due to the presence of ancient cultivars that still exhibit the phenotypic characteristics of wild grapes.  相似文献   

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