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 0 毫秒
1.
The hypothesis that both genetic and linguistic similarities among Eurasian and North African populations are due to demic diffusion of neolithic farmers is tested against a wide database of allele frequencies. Demic diffusion of farming and languages from the Near East should have determined clines in areas defined by linguistic criteria; the alternative hypothesis of cultural transmission does not predict clines. Spatial autocorrelation analysis shows significant gradients in three of the four linguistic families supposedly affected by neolithic demic diffusion; the Afroasiatic family is the exception. Many such gradients are not observed when populations are jointly analyzed, regardless of linguistic classification. This is incompatible with the hypothesis that major cultural transformations in Eurasia (diffusion of related languages and spread of agriculture) took place without major demographic changes. The model of demic diffusion seems therefore to provide a mechanism explaining coevolution of linguistic and biological traits in much of the Old World. Archaeological, linguistic, and genetic evidence agree in suggesting a multidirectional process of gene flow from the Near East in the neolithic. However, the possibility should be envisaged that some allele frequency patterns can predate the neolithic and depend on the initial spread of Homo sapiens sapiens from Africa into Eurasia. © 1994 Wiley-Liss, Inc.  相似文献   

2.
The results of more than 100 archaeobotanical investigations from south-western Germany have been arranged into chronological groups and analyzed with a spreadsheet to obtain presence data and the numbers of taxa present in the various time periods. They show an increase in the number of plant taxa cultivated in gardens since the Roman period, a decrease in the crops that were the earliest to be cultivated, especially emmer, and an increase of spelt, rye and oats in the course of time. New crop weeds appear, including an increasing number of southern plants originating from open vegetation. This is more likely to be a result of the intensification of agriculture than from increased human mobility. The crop weeds, grouped together according to their requirements for soil nutrients, show increasing soil acidification through the course of time.  相似文献   

3.
Morphological evidence for a Multiregional (MR) model of human origins is suggested by a series of “linking traits” seen in the crania of late Javanese Homo erectus from Ngandong and anatomically modern Australian crania. A few studies that consider the genetic, structural, or functional aspects of these regional traits suggest their appearance is heavily influenced not by shared phylogeny but by a common “strong” masticatory pattern. Using dental occlusal areas, external mandibular metrics, internal biomechanical properties of the mandibular corpus measured from CT scans, and nonmetric traits associated with the attachment of masticatory muscles, we test the hypothesis that Australians exhibit evidence of a “strong” masticatory pattern. We use a mixed-sex comparative human sample (n = 415) that includes precontact Alaskans from Point Hope and the Aleutian Islands, Californians, Peruvians, an urban forensic sample, and the late Pleistocene Afalou-Taforalt sample. In comparison with recent humans known to exhibit such patterns, Australian mandibles show none of the expected changes related to producing and dissipating heavy occlusal loads. This is true regardless of whether external or internal mandibular dimensions are considered, albeit Australians show large occlusal areas and relatively large section modulus indices. Thus, a prime functional argument proposed for the origin of some Australian regional features is not supported by these data.  相似文献   

4.
The transition from hunting and gathering to agriculture in Europe is associated with demographic changes that may have shifted the human gene pool of the region as a result of an influx of Neolithic farmers from the Near East. However, the genetic composition of populations after the earliest Neolithic, when a diverse mosaic of societies that had been fully engaged in agriculture for some time appeared in central Europe, is poorly known. At this period during the Late Neolithic (ca. 2,800-2,000 BC), regionally distinctive burial patterns associated with two different cultural groups emerge, Bell Beaker and Corded Ware, and may reflect differences in how these societies were organized. Ancient DNA analyses of human remains from the Late Neolithic Bell Beaker site of Kromsdorf, Germany showed distinct mitochondrial haplotypes for six individuals, which were classified under the haplogroups I1, K1, T1, U2, U5, and W5, and two males were identified as belonging to the Y haplogroup R1b. In contrast to other Late Neolithic societies in Europe emphasizing maintenance of biological relatedness in mortuary contexts, the diversity of maternal haplotypes evident at Kromsdorf suggests that burial practices of Bell Beaker communities operated outside of social norms based on shared maternal lineages. Furthermore, our data, along with those from previous studies, indicate that modern U5-lineages may have received little, if any, contribution from the Mesolithic or Neolithic mitochondrial gene pool.  相似文献   

5.
Recent studies of the effects of hypoxia on human growth and adult size have focused mainly on the variability of single measurements. In this paper we explore changes with altitude and ethnicity (Spanish-Aymara ancestry) in body proportions of permanent residents of an altitudinal gradient (0–4000 meters) in northern Chile. Body proportion or shape is assessed by anthropometric indices and principal components of 14 bone measurements. Ethnicity independent of altitude had its major effect on proportions and a lesser effect on size. Aymara had larger relative sitting heights, broader builds and prominent facial development as compared to non-Aymara (Spanish). Altitude also affected head and chest proportions during growth. On the whole, the effects of altitude and Aymara ancestry on the measurements and indices were independent (not necessarily of similar direction or magnitude), in spite of a correlation of ethnicity and altitude in Andean populations.  相似文献   

6.
This article examines Greek-Cypriot teachers' constructions of Turkish-speaking children's identities in the Greek-Cypriot educational system. Drawing on interviews and classroom observations from a two-year ethnographic study conducted in three primary schools in the Republic of Cyprus, the author explores how Turkish-speaking children enrolled in these schools are racialized, ethnicized and classed within the dominant discourse of Greek-Cypriot teachers. The article discusses how the homogenized perceptions expressed by the majority of participating teachers in this study are illustrative of structural racism that reinforces these constructions in teaching practices. Yet, at the same time, resistance is present in the discourse and practice of a few teachers; this resistance is expressed through a counter-positioning of the ‘normal/ized’ identities of Turkish-speaking children. The author argues that without structural transformation, the fact and practice of racism/nationalism/classism will go unaltered in schools.  相似文献   

7.
This paper presents an overview of archaeobotanical finds of Linum usitatissimum from Neolithic and Bronze Age Greece, bringing together published records of this plant as well as some recently retrieved, unpublished finds. In addition, charred flax seed concentrations from five prehistoric sites from the region of Macedonia in northern Greece, are examined in detail. The Neolithic sites are Makriyalos, Mandalo, Arkadikos, Dikili Tash, dated to the Late and Final Neolithic and Archondiko, dated to the end of the Early Bronze Age. Archaeobotanical composition and contextual information are used in order to explore the cultivation and potential uses of flax at each site. By the 5th millennium b.c. a flax weed flora had probably developed in the region. The use of flax seed for oil extraction and flax stems for flax fibre preparation can only be speculated upon and these uses are discussed within the context of other archaeological finds related to plant oil production and weaving. It is also possible that flax may have been used for medicinal purposes. Despite a striking paucity in archaeobotanical remains from southern Greece, textual evidence available from the Mycenean palace archives in Linear B clearly documents the cultivation of flax and flax fibre production.  相似文献   

8.
Cook R 《Biology letters》2012,8(5):856-859
Since their discovery, mirror neurons-units in the macaque brain that discharge both during action observation and execution-have attracted considerable interest. Whether mirror neurons are an innate endowment or acquire their sensorimotor matching properties ontogenetically has been the subject of intense debate. It is widely believed that these units are an innate trait; that we are born with a set of mature mirror neurons because their matching properties conveyed upon our ancestors an evolutionary advantage. However, an alternative view is that mirror neurons acquire their matching properties during ontogeny, through correlated experience of observing and performing actions. The present article re-examines frequently overlooked neurophysiological reports of 'tool-use' and 'audiovisual' mirror neurons within the context of this debate. It is argued that these findings represent compelling evidence that mirror neurons are a product of sensorimotor experience, and not an innate endowment.  相似文献   

9.
10.
For a long time, anthropological and genetic research on the Neolithic revolution in Europe was mainly concentrated on the mechanism of agricultural dispersal over different parts of the continent. Recently, attention has shifted towards population processes that occurred after the arrival of the first farmers, transforming the genetically very distinctive early Neolithic Linear Pottery Culture (LBK) and Mesolithic forager populations into present-day Central Europeans. The latest studies indicate that significant changes in this respect took place within the post-Linear Pottery cultures of the Early and Middle Neolithic which were a bridge between the allochthonous LBK and the first indigenous Neolithic culture of north-central Europe—the Funnel Beaker culture (TRB). The paper presents data on mtDNA haplotypes of a Middle Neolithic population dated to 4700/4600–4100/4000 BC belonging to the Brześć Kujawski Group of the Lengyel culture (BKG) from the Kuyavia region in north-central Poland. BKG communities constituted the border of the “Danubian World” in this part of Europe for approx. seven centuries, neighboring foragers of the North European Plain and the southern Baltic basin. MtDNA haplogroups were determined in 11 individuals, and four mtDNA macrohaplogroups were found (H, U5, T, and HV0). The overall haplogroup pattern did not deviate from other post-Linear Pottery populations from central Europe, although a complete lack of N1a and the presence of U5a are noteworthy. Of greatest importance is the observed link between the BKG and the TRB horizon, confirmed by an independent analysis of the craniometric variation of Mesolithic and Neolithic populations inhabiting central Europe. Estimated phylogenetic pattern suggests significant contribution of the post-Linear BKG communities to the origin of the subsequent Middle Neolithic cultures, such as the TRB.  相似文献   

11.
12.
Univariate and multivariate study of 22 dimensions describing overall body proportions in 34 primate genera, has shown that these quantities effect a separation between the principal taxonomic divisions of the Primates: Prosimii, Ceboidea, Cercopithecoidea and Hominoidea. The last three do not, however, link to form a single unit, and the separation between the Ceboidea and Cercopithecoidea is imperfect. Some grouping within these major divisions appears, in certain aspects, to be of functional (locomotor), rather than of purely taxonomic, significance. For instance, within the Prosimii, the genera Microcebus, Galago and Tarsius (the two latter being saltatory forms, while leaping is a component of the locomotor pattern of the first) are associated, while within the apes, the Asiatic forms Hylobates, Symphalangus and Pongo (all brachiators) tend to be grouped, as also do the African forms Pan and Gorilla (both, to a large extent, secondarily terrestrial in habit).
The measures especially prominent in effecting this pattern of discrimination are: relative foot length, relative lower limb length and length of foot relative to lower limb length.
Similar, if less clearly defined results emerge if groups of dimensions relating to individual body regions (forelimb, hindlimb, head and trunk) are analysed separately.
The apparent failure of compounds of the measures of the limbs to give an anticipated close reflection of locomotor function stems possibly from the fact that the available dimensions are of an overall nature rather than a reflection of specific biomechanical functions. Such sub-division, according with locomotor pattern as seems to emerge from this study, appears, in fact, to be little more than that implied in current taxonomic schemata.  相似文献   

13.
14.
This paper examines the socio-economic variation in height and weight using data from the German Socio-Economic Panel. Results reinforce previous research insofar as height is associated with socio-economic differences. For example, a low maternal schooling level or a lower position in the income distribution is negatively correlated with the height of West Germans. Furthermore, there is a west-east and a north-south gradient in height in Germany. BMI is also determined by individuals' characteristics with similar underlying patterns. That is, in both West and East Germany, women with low income and low education have a higher BMI whereas the better educated women weigh less.  相似文献   

15.
D A Leon 《Twin research》2001,4(5):321-326
Twin studies have a contribution to make to the debate concerning the foetal origins of adult disease. Twins are growth retarded compared to singletons and experience post-natal catch-up growth. However, there is no evidence that twins are at increased risk of cardiovascular disease. Studying whether discordance in size at birth within monozygotic twin pairs is predictive of discordance in later life disease should help resolve whether the association between size at birth and later disease is due to common genetic factors. Results from studies of blood pressure in childhood and adult life looking at these within twin effects are far from conclusive. There are, however, methodological problems in the interpretation of these results, not least of which is the relatively small numbers of twin pairs studied. Studies exploring the effect of zygosity and chorion type on later disease provide may provide a useful extension of the research agenda. In summary, twin studies to date have raised more questions about the foetal origins hypothesis than they have resolved.  相似文献   

16.
17.
Soil samples from a late Neolithic stone cist in Hamneda, southern Sweden, were pollen analysed. The results of the analysis suggest that the local vegetation at the time of the burial was a half-open woodland with pasture and small-scale cereal growing, intermingled with stands ofTilia (lime),Quercus (oak) andCorylus (hazel). The analysis also gives unique information on the burial ritual. High pollen percentages ofHordeum type,Triticum type and undifferentiated Cerealia from among the shards of a pot deposited in the cist show that the pot originally contained cereal grains, bread, porridge, gruel or beer. Furthermore, the analysis shows that flowers ofAnemone nemorosa were deposited on or beneath the dead body in the cist.  相似文献   

18.
Starch-gel electrophoresis was used to assess the level and distribution of genetic variation in juvenile European seabass sampled from five different nursery grounds along the coast of Portugal between November 1992 and February 1994. Thirty-eight loci were examined, of which six ( AAT-3*, ADA*, GPI-1*, GPI-2*, G3PDH-2*, SOD* ) were polymorphic at the 99% level and were used in population surveys. Low but statistically significant multilocus F ST values suggest that population structuring exists along the Portuguese coast. There is some restriction in gene flow between the population at Faro and all other sites to the north.  相似文献   

19.
Body mass and structural properties of the femoral and tibial midshafts of the "Iceman," a late Neolithic (5,200 BP) mummy found in the Tyrolean Alps, are determined from computed tomographic scans of his body, and compared with those of a sample of 139 males spanning the European early Upper Paleolithic through the Bronze Age. Two methods, based on femoral head breadth and estimated stature/bi-iliac (pelvic) breath, yield identical body-mass estimates of 61 kg for the Iceman. In combination with his estimated stature of 158 cm, this indicates a short but relatively wide or stocky body compared to our total sample. His femur is about average in strength compared to our late Neolithic (Eneolithic) males, but his tibia is well above average. His femur also shows adaptations for his relatively broad body (mediolateral strengthening), while his tibia shows adaptations for high mobility over rough terrain (anteroposterior strengthening). In many respects, his tibia more closely resembles those of European Mesolithic rather than Neolithic males, which may reflect a more mobile lifestyle than was characteristic of most Neolithic males, perhaps related to a pastoral subsistence strategy. There are indications that mobility in general declined between the European Mesolithic and late Neolithic, and that body size and shape may have become more variable throughout the continent following the Upper Paleolithic.  相似文献   

20.
The origin of the unique body plan of turtles has long been one of the most intriguing mysteries in evolutionary morphology. Discoveries of several new stem-turtles, together with insights from recent studies on the development of the shell in extant turtles, have provided crucial new information concerning this subject. It is now possible to develop a comprehensive scenario for the sequence of evolutionary changes leading to the formation of the turtle body plan within a phylogenetic framework and evaluate it in light of the ontogenetic development of the shell in extant turtles. The fossil record demonstrates that the evolution of the turtle shell took place over millions of years and involved a number of steps.  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