991 resultados para Ancient human cranium
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As a result of climate change over the past 5000 years the Sahara changed from savannah to a desert landscape. The beds of ancient lakes are home to snail shells and the petrified roots of trees and shrubs. Examples of human occupation can also be seen in the form of fireplaces and discarded tools. Examination of the geological history of these sites can give a clearer picture of how the climate changed and how humans coped with these changes.
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In the human genome, members of the FoxC, FoxF, FoxL1, and FoxQ1 gene families are found in two paralagous clusters. Here we characterize all four gene families in the dogfish Seyliorhinus canicula, a member of the cartilaginous fish lineage that diverged before the radiation of osteichthyan vertebrates. We identify two FoxC genes, two FoxF genes, and single FoxQ1 and FoxL1 genes, demonstrating cluster duplication preceded the radiation of gnathostomes. The expression of all six genes was analyzed by in situ hybridization. The results show conserved expression of FoxL1, FoxF, and FoxC genes in different compartments of the mesoderm and of FoxQ1 in pharyngeal endoderm and its derivatives, confirming these as ancient sites of Fox gene expression, and also illustrate multiple cases of lineage-specific expression domains. Comparison to invertebrate chordates shows that the majority of conserved vertebrate expression domains mark tissues that are part of the primitive chordate body plan.
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This paper considers the contribution of pollen analysis to conservation strategies aimed at restoring planted ancient woodland. Pollen and charcoal data are presented from organic deposits located adjacent to the Wentwood, a large planted ancient woodland in southeast Wales. Knowledge of the ecosystems preceding conifer planting can assist in restoring ancient woodlands by placing fragmented surviving ancient woodland habitats in a broader ecological, historical and cultural context. These habitats derive largely from secondary woodland that regenerated in the 3rd–5th centuries A.D. following largescale clearance of Quercus-Corylus woodland during the Romano-British period. Woodland regeneration favoured Fraxinus and Betula. Wood pasture and common land dominated the Wentwood during the medieval period until the enclosures of the 17th century. Surviving ancient woodland habitats contain an important Fagus component that probably reflects an earlier phase of planting preceding conifer planting in the 1880s. It is recommended that restoration measures should not aim to recreate static landscapes or woodland that existed under natural conditions. Very few habitats within the Wentwood can be considered wholly natural because of the long history of human impact. In these circumstances, restoration should focus on restoring those elements of the cultural landscape that are of most benefit to a range of flora and fauna, whilst taking into account factors that present significant issues for future conservation management, such as the adverse effects from projected climate change.
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Evidence increasingly suggests that sub-Saharan Africa is at the center of human evolution and understanding routes of dispersal “out of Africa” is thus becoming increasingly important. The Sahara Desert is considered by many to be an obstacle to these dispersals and a Nile corridor route has been proposed to cross it. Here we provide evidence that the Sahara was not an effective barrier and indicate how both animals and humans populated it during past humid phases. Analysis of the zoogeography of the Sahara shows that more animals crossed via this route than used the Nile corridor. Furthermore, many of these species are aquatic. This dispersal was possible because during the Holocene humid period the region contained a series of linked lakes, rivers, and inland deltas comprising a large interlinked waterway, channeling water and animals into and across the Sahara, thus facilitating these dispersals. This system was last active in the early Holocene when many species appear to have occupied the entire Sahara. However, species that require deep water did not reach northern regions because of weak hydrological connections. Human dispersals were influenced by this distribution; Nilo-Saharan speakers hunting aquatic fauna with barbed bone points occupied the southern Sahara, while people hunting Savannah fauna with the bow and arrow spread southward. The dating of lacustrine sediments show that the “green Sahara” also existed during the last interglacial (∼125 ka) and provided green corridors that could have formed dispersal routes at a likely time for the migration of modern humans out of Africa.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The Khoisan people from Southern Africa maintained ancient lifestyles as hunter-gatherers or pastoralists up to modern times, though little else is known about their early history. Here we infer early demographic histories of modern humans using whole-genome sequences of five Khoisan individuals and one Bantu speaker. Comparison with a 420 K SNP data set from worldwide individuals demonstrates that two of the Khoisan genomes from the Ju/'hoansi population contain exclusive Khoisan ancestry. Coalescent analysis shows that the Khoisan and their ancestors have been the largest populations since their split with the non-Khoisan population similar to 100-150 kyr ago. In contrast, the ancestors of the non-Khoisan groups, including Bantu-speakers and non-Africans, experienced population declines after the split and lost more than half of their genetic diversity. Paleoclimate records indicate that the precipitation in southern Africa increased similar to 80-100 kyr ago while west-central Africa became drier. We hypothesize that these climate differences might be related to the divergent-ancient histories among human populations.
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Liz Bryan begins her book with a description of the Canadian Plains:" . .. a voluptuous landscape of hills and valleys and plains, of lakes and tiny twinkling potholes, of flower-filled coulees and vast sand dunes." Her emphasis throughout on the landscape of southern Saskatchewan and Alberta is necessary since the ancient monuments she describes only truly resonate within this setting. Indeed, almost every page of this attractive book is adorned with at least two color images-of scenery, stone features, artifacts, and aboriginal events. She then proceeds to an eclectic overview of the archaeological record of the Plains of Saskatchewan and Alberta, including the earliest human evidence, such as the Clovis points from the Wally's Beach site, Alberta, where the trackways of mammoths, camels, and muskoxen were miraculously and briefly exposed in the late 1990s. There is one perplexing error, however-the attribution of the extinction of the ice age bestiary, about 12,000 years ago, to the meteorite that felled the dinosaurs!
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Human endogenous retroviruses (HERVs) arise from ancient infections of the host germline cells by exogenous retroviruses, constituting 8% of the human genome. Elevated level of envelope transcripts from HERVs-W has been detected in CSF, plasma and brain tissues from patients with Multiple Sclerosis (MS), most of them from Xq22.3, 15q21.3, and 6q21 chromosomes. However, since the locus Xq22.3 (ERVWE2) lack the 5' LTR promoter and the putative protein should be truncated due to a stop codon, we investigated the ERVWE2 genomic loci from 84 individuals, including MS patients with active HERV-W expression detected in PBMC. In addition, an automated search for promoter sequences in 20 kb nearby region of ERVWE2 reference sequence was performed. Several putative binding sites for cellular cofactors and enhancers were found, suggesting that transcription may occur via alternative promoters. However, ERVWE2 DNA sequencing of MS and healthy individuals revealed that all of them harbor a stop codon at site 39, undermining the expression of a full-length protein. Finally, since plaque formation in central nervous system (CNS) of MS patients is attributed to immunological mechanisms triggered by autoimmune attack against myelin, we also investigated the level of similarity between envelope protein and myelin oligodendrocyte glycoprotein (MOG). Comparison of the MOG to the envelope identified five retroviral regions similar to the Ig-like domain of MOG. Interestingly, one of them includes T and B cell epitopes, capable to induce T effector functions and circulating Abs in rats. In sum, although no DNA substitutions that would link ERVWE2 to the MS pathogeny was found, the similarity between the envelope protein to MOG extends the idea that ERVEW2 may be involved on the immunopathogenesis of MS, maybe facilitating the MOG recognizing by the immune system. Although awaiting experimental evidences, the data presented here may expand the scope of the endogenous retroviruses involvement on MS pathogenesis
A river runs through it - ancient DNA data on the neolithic populations of the Great Hungarian Plain
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This thesis was part of a multidisciplinary research project funded by the German Research Foundation (“Bevölkerungsgeschichte des Karpatenbeckens in der Jungsteinzeit und ihr Einfluss auf die Besiedlung Mitteleuropas”, grant no. Al 287/10-1) aimed at elucidating the population history of the Carpathian Basin during the Neolithic. The Carpathian Basin was an important waypoint on the spread of the Neolithic from southeastern to central Europe. On the Great Hungarian Plain (Alföld), the first farming communities appeared around 6000 cal BC. They belonged to the Körös culture, which derived from the Starčevo-Körös-Criş complex in the northern Balkans. Around 5600 cal BC the Alföld-Linearbandkeramik (ALBK), so called due to its stylistic similarities with the Transdanubian and central European LBK, emerged in the northwestern Alföld. Following a short “classical phase”, the ALBK split into several regional subgroups during its later stages, but did not expand beyond the Great Hungarian Plain. Marking the beginning of the late Neolithic period, the Tisza culture first appeared in the southern Alföld around 5000 cal BC and subsequently spread into the central and northern Alföld. Together with the Herpály and Csőszhalom groups it was an integral part of the late Neolithic cultural landscape of the Alföld. Up until now, the Neolithic cultural succession on the Alföld has been almost exclusively studied from an archaeological point of view, while very little is known about the population genetic processes during this time period. The aim of this thesis was to perform ancient DNA (aDNA) analyses on human samples from the Alföld Neolithic and analyse the resulting mitochondrial population data to address the following questions: is there population continuity between the Central European Mesolithic hunter-gatherer metapopulation and the first farming communities on the Alföld? Is there genetic continuity from the early to the late Neolithic? Are there genetic as well as cultural differences between the regional groups of the ALBK? Additionally, the relationships between the Alföld and the neighbouring Transdanubian Neolithic as well as other European early farming communities were evaluated to gain insights into the genetic affinities of the Alföld Neolithic in a larger geographic context. 320 individuals were analysed for this study; reproducible mitochondrial haplogroup information (HVS-I and/or SNP data) could be obtained from 242 Neolithic individuals. According to the analyses, population continuity between hunter-gatherers and the Neolithic cultures of the Alföld can be excluded at any stage of the Neolithic. In contrast, there is strong evidence for population continuity from the early to the late Neolithic. All cultural groups on the Alföld were heavily shaped by the genetic substrate introduced into the Carpathian Basin during the early Neolithic by the Körös and Starčevo cultures. Accordingly, genetic differentiation between regional groups of the ALBK is not very pronounced. The Alföld cultures are furthermore genetically highly similar to the Transdanubian Neolithic cultures, probably due to common ancestry. In the wider European context, the Alföld Neolithic cultures also highly similar to the central European LBK, while they differ markedly from contemporaneous populations of the Iberian Peninsula and the Ukraine. Thus, the Körös culture, the ALBK and the Tisza culture can be regarded as part of a “genetic continuum” that links the Neolithic Carpathian Basin to central Europe and likely has its roots in the Starčevo -Körös-Criş complex of the northern Balkans.
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Abstract. Organic matter preserved in Lake Ohrid sediments originates from aquatic and terrestrial sources. Its variable composition reflects climate-controlled changes in the lake basin’s hydrology and related organic matter export, i.e. changes in primary productivity, terrestrial plant matter input and soil erosion. Here, we present first results from lipid biomarker investigations of Lake Ohrid sediments from two near-shore settings: site Lz1120 near the southern shore, with low-lying lands nearby and probably influenced by river discharge, and site Co1202 which is close to the steep eastern slopes. Variable proportions of terrestrial n-alkanoic acids and n-alkanols as well as compositional changes of !- hydroxy acids document differences in soil organic matter supply between the sites and during different climate stages (glacial, Holocene, 8.2 ka cooling event). Changes in the vegetation cover are suggested by changes in the dominant chain length of terrestrial n-alkanols. Effective microbial degradation of labile organic matter and in situ contribution of organic matter derived from the microbes themselves are both evident in the sediments. We found evidence for anoxic conditions within the photic zone by detecting epicholestanol and tetrahymanol from sulphur-oxidising phototrophic bacteria and bacterivorous ciliates and for the influence of a settled human community from the occurrence of coprostanol, a biomarker for human and animal faeces (pigs, sheep, goats), in an early Holocene sample. This study illustrates the potential of lipid biomarkers for future environmental reconstructions using one of Europe’s oldest continental climate archives, Lake Ohrid.
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A depiction of the ancient Hebrew understanding of the human being must take into account the fact that the Bible does not contain a systematic anthropology, but unfolds the multiplicity of human existence inductively, aspectively, and in narrative fashion. In comparison to Greek body/soul dualism, but also in the context of body-(de-)construction and gender debates, this circumstance makes it a treasure trove of interesting, often contrasting recollections and insights with liberating potential. This assertion will be illustrated concretely in terms of the nexus points of the human body (throat, heart, and womb), the relationship of humans to animals and angels, and the questions of the power and value of a human being.
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The Iron Age cemetery of Münsingen in Switzerland with 220 abundantly equipped burials marked a milestone for Iron Age research. The horizontal spread throughout the time of its occupancy laid the foundation for the chronology system of the Late Iron Age. Today, skulls of 77 individuals and some postcranial bones are still preserved. The aim of the study was to obtain information about diet, mobility and social stratification of the individuals. Stable isotope ratios of carbon, nitrogen and sulphur were analysed for 63 individuals. For all of them C3 plants were found to be the staple food. There are significant differences between males and females in δ13C and δ15N values. This points to a gender restriction in the access to animal protein with males probably having more access to meat and dairy products. Differences in δ15N values were also observed for different age classes. δ34S values indicate a terrestrial-based diet with no significant intake of marine or freshwater fish. Seven adults with enriched δ34S values might have immigrated to Münsingen, four of which were found in the oldest part of the cemetery. Furthermore, possible changes of the vegetation are indicated by the more positive stable carbon ratios in the later phases. The results lead to the suggestion that especially males buried with weapons might have played a special role in the Iron Age society.
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Human bone is the most direct source for reconstructing health and living conditions of ancient populations. However, many diseases remain undetected in palaeopathology. Möller-Barlow disease (scurvy) is a historically well-documented metabolic disease and must have been common in clinical and sub-clinical severity. Due to long incubation periods and the subtle nature of bone changes osteological evidence is relatively rare (Brickley & Ives 2008). Möller-Barlow disease is caused by deficiency of dietary vitamin C (ascorbic acid) and evokes symptoms like fatigue, haemorrhage, inflammations, delayed wound healing and pain. Vitamin C is a cofactor for the hydroxylation of the amino acids proline and lysine which are essential for the production of intact connective tissue by cross-linking the propeptides in collagen. In a preliminary study we tested the detectability of Möller-Barlow disease by analysis of relative quantitative variability of hydroxylated amino acids in collagen (Pendery & Koon 2013). Samples (N=9) were taken from children with (n=3, cranium, femur, tibia) and without (n=4, cranium, femur, tibia) apparent bone reactions indicative of Möller-Barlow disease, as well as from adults with lethal traumata (n=2; negative controls). The skeletal remains originated from two early medieval cemeteries from Switzerland. Gas chromatographic (GC) analysis revealed minor differences between the samples. So far children with no pathologic alterations had fairly same values as negative controls while children with bone reactions paradoxically exhibited even slightly higher values of hydroxyproline and hydroxylysine. Future research demands for larger sample size and has to discuss sampling strategies. Beside possible misdiagnosis of Möller-Barlow disease it is arguable if only the newly built bone should be analysed even though this could lead to problems related to small sample quantity. It also remains to be seen to which extent varying turnover rates of different skeletal elements, especially in children, must be taken into account.