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1.
The purpose of this study is to obtain demographic data regarding the medieval population buried at the Yuigahama-minami site in Kamakura, Japan, and to detect a secular trend in the life expectancy of Japanese population over the last several thousand years. The Yuigahama-minami skeletal sample consists of 260 individuals, including 98 subadults (under 20 years old) and 162 adults. A Yuigahama-minami abridged life-table analysis yielded a life expectancy at birth (e0) of 24.0 years for both sexes, a life expectancy at age 15 years (e15) of 15.8 years for males, and an e15 of 18.0 years for females. The reliability of the estimated e0 was confirmed by analysis of the juvenility index. Demographic profiles comparing the Yuigahama-minami series with other skeletal series indicated that both the survivorship curve and life expectancy of the Yuigahama-minami sample are similar to those of the Mesolithic-Neolithic Jomon population, but are far lower than those of the early modern Edo population. These comparisons strongly suggest that life expectancy changed little over the thousands of years between the Mesolithic-Neolithic Jomon and medieval periods, but then improved remarkably during the few hundred years between the medieval period and early modern Edo period. The short-lived tendency of the Yuigahama-minami sample does not contradict the archaeological hypothesis of unsanitary living conditions in medieval Kamakura. This is the first investigation to address the demographic features of a medieval population in Japan, and will help refine our understanding of long-term trends in the demographic profiles of inhabitants of Japan.  相似文献   

2.
Fifty-five samples of human and animal fossil skeletal remains (sheep, cattle, horse and deer) collected at six different sites in European Russia were measured for the oxygen isotopic composition of bone phosphate (δ18Op) and for the carbon (δ13C) and nitrogen (δ15N) isotopic composition of bone collagen. The age of these samples ranges from 10 500 to 200 BP covering a time period of about 10 000 years. The samples come from the steppe area of southern European Russia, from the northern Black Sea coast and from an area near Moscow. From the results obtained it can be suggested that the steppe tribes were nomads, at least after 4000 BP, and that they probably moved from east to west and vice-versa (i.e. from the Volga area to the Black Sea coast). C4 plants were present in the steppe area since 5000 BP. On the contrary, in the area near Moscow and on the Black Sea coast no C4 species are documented at least until 5000 and 6000 BP respectively. Arid environmental conditions dominate the steppe area even though the N isotope values suggest a climatic improvement-taking place from 5000 BP towards present in terms of more humid conditions. As regards diet, it seems that the subsistence of the steppe populations was based mainly on terrestrial food and in particular on sheep with a minor contribution of fish. The populations from the Moscow area probably had a permanent economy mainly based on fishing.  相似文献   

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We quantitatively examined the differences in the size and proportion of the Japanese macaque (Macaca fuscata) by comparing the Early Jomon specimens from Torihama shell-midden, Fukui Prefecture and modern specimens from Fukui Prefecture. The purpose of this study was to explore the temporal change in the proportion and size of teeth of the Japanese macaques based on the quantified data. The result of measurements of lower premolars and molars demonstrated that sexual dimorphism was evident only among the modern specimens where the females were significantly smaller than males. The size of male Torihama specimens was within the range of the modern population, whereas the size of the female Torihama specimens was significantly larger than the modern female population. The proportional pattern of premolars and molars for male and female Torihama specimens also differed. The results may suggest a possible difference in the degree of size reduction between males and females since the last glacial period.Morphometric analysis of mandibular cheek teeth from Torihama Shell-midden  相似文献   

5.
Local and regional vegetation since the last glacial period was reconstructed on the basis of a palynological study of sediment at Iwaya, in the Sea of Japan area, western Japan. During the interstade (before about 30 000 years BP), forests were composed predominantly ofCryptomeria japonica withTsuga sieboldii and cool-temperate deciduous broad-leaved trees. In the pre-full-glacial, the full-glacial and the early late-glacial (30 000-12 000 years BP), forests were dominated by temperate (montane) and boreal (subalpine) Pinaceae andBetula. During the early full-glacial, the pinaceous forests were mixed with cool-temperate trees such asFagus crenata. In the late full-glacial (18 000-16 000 years BP), the maximum development of pinaceous conifer forests was recognized. Cool-temperate broad-leaved forests composed mainly ofF. crenata andQuercus (Lepidobalanus) replaced the pinaceous forests at about 12 000 years BP and were maintained to the early postglacial.Cryptomeria japonica was distributed around the Mikata lowland during the last glacial.Cryptomeria japonica, which began to increase at 16 000 years BP, increased abruptly in the early postglacial and spread throughout the postglacial in the lowlands. After 6300 years BP, lucidophyllous forests composed mainly ofQuercus (Cyclobalanopsis) andCastanopsis were established in the Mikata district; this was later than in the inland and the Pacific Ocean areas in the Kinki region, western Japan. In historic times (afterca 2000 years BP), secondary forest ofPinus densiflora, which can grow as a pioneer in disturbed habitats, spread.  相似文献   

6.
For sustainable use and suitable management of larch plantations, we must clarify the ecophysiological responses of larch species to environmental changes. The physical environment has been changing dramatically, e.g., increase in atmospheric CO2 concentration ([CO2]), nitrogen (N) deposition, and atmospheric ozone concentration ([O3]), and these changes may negatively affect growth of larch species. This review summarizes the previous experimental studies on the ecophysiological responses of larch species to elevated [CO2], soil acidification, elevated [O3], and N load. Based on the advanced studies, although elevated [CO2] will stimulate the productivity of larch, increase of [O3] and severe soil acidification will reduce it. Increase of N deposition, at least, will not negatively affect larch productivity. Finally, we propose the future direction for investigation to understand the mechanism of the responses of larch species and to predict the associated risk.  相似文献   

7.
Animal remains are well preserved in archaeological sites, especially the terp sites, of the Wadden Sea area of Denmark, Germany and The Netherlands. Here, we provide an overview on the wild mammals, birds, fishes, amphibians and molluscs found in coastal sites dating from 2700 to 2600 B.C. and 700 B.C. to A.D. 1600. Coastal people used a variety of animal species for food and other purposes. Hunting, fowling, fishing and agriculture did not have much influence on wild stocks in the period from the late Bronze Age/early Iron Age until the late Middle Ages. However, large changes to the landscape were made in the late Middle Ages by diking and damming. As a result, some species such as the northern vole (Microtus oeconomus) and the natterjack toad (Bufo calamita) disappeared from the area except for some dune districts on the islands, and others became rare, such as the grey seal (Halichoerus grypus) and the lagoon cockle (Cerastoderma lamarcki). New habitats arose for birds of dry meadows and fields, like lapwing (Vanellus vanellus) and black-tailed godwit (Limosa limosa). Sturgeon (Acipenser sturio) disappeared from the Wadden Sea within a few decades since A.D. 1890 due to the destruction of spawning grounds by damming and high exploitation pressure. Our findings are important for the ecological history of the region.  相似文献   

8.
The Neolithic and Bronze Age (4400-1570 B.C.) pile dwellings of Concise-sous-Colachoz on the shore of Lake Neuchatel (Canton of Vaud, western Switzerland), known as an archaeological site for more than 140 years, were recently re-investigated due to rescue excavations. Plant macrofossil analyses were done for several Neolithic occupation phases (3868-2440 B.C. the Cortaillod classique, Cortaillod moyen, Cortaillod tardif and Auvernier periods) with a focus on cereal remains, and additionally, archaeological deposits dating to the Cortaillod moyen culture (3710-3677 B.C.) were studied in detail. The preliminary study of cereal macrofossil remains from all the mentioned Neolithic phases show that the most important cereals were Triticum aestivum/durum/turgidum (naked wheat), T. monococcum (einkorn) and Hordeum vulgare (barley). The preferences for specific crops did obviously not alter significantly through time, but, extraordinarily, significant amounts of einkorn continued to be grown for at least 1400 years during the Neolithic period. Other cultivated plants were Pisum sativum (pea), Linum usitatissimum (flax), and Papaver somniferum (opium poppy). Additionally to the seeds, capsule fragments of opium poppy were found in the Cortaillod moyen deposits. These represent the first finds of uncharred capsule fragments in Europe. Compared with other central European sites, opium poppy was very common during the 38th and 37th cent. B.C. and obviously less appreciated towards the end of the Neolithic in the western part of Switzerland. In central Switzerland the trends seem different: there opium poppy was mainly used during the Late Neolithic period. This may be due to cultural differences within contemporaneous human societies. Wild fruits which were collected as plant resources during the Cortaillod moyen period included Prunus spinosa (sloe), Cornus sanguinea (dogwood), Malus sylvestris (apple), Rubus idaeus/caesius/fruticosus (raspberry/dewberry/blackberry), Fragaria vesca (wild strawberry), Rosa sp. (hip), Quercus sp. (acorn), Corylus avellana (hazelnut), and Fagus sylvatica (beechnut), among others. Compared with other Neolithic sites in westem and central Switzerland the local population of Concise-sous-Colachoz used few sloes, while dogwood fruits were in use throughout the Neolithic period at Lake Neuchatel. Received September 4, 2001 / Accepted May 13, 2002  相似文献   

9.
North Korea has survived the breakdown of the communist bloc and has been immune to the democratization process of the 1990s. In spite of national famines and economic collapse, the totalitarian regime in Pyongyang maintains a firm grip on its power. Reliable information on the population's biosocial welfare is scarce. Using height and weight data of 5991 North Korean pre-school children measured in 2002, we investigate determinants of height-for-age z-score (HAZ), weight-for-age z-score (WAZ) and weight-for-height z-score (WHZ) as an indicator for child health. We find a statistically significant impact of the age of the child and of the mother, as well as the sex of the child on HAZ and WAZ. In contrast, social status and wealth proxies at the individual and household level are not statistically significant possibly because of errors in these variables. We do not find a consistent effect for geographic regions or for rural-urban residents either. Yet, urban provinces seem to be better-off. Most importantly, we find that children living in families who benefit from food aid of the United Nations are healthier in terms of HAZ, WAZ and WHZ than those depending on the government. Hence, further delivery of United Nations food aid is likely to mitigate the effects of the ongoing food crisis in North Korea.  相似文献   

10.
Cell surface carbohydrates present on BG01 human embryonic stem cells after 28 days of differentiation were examined using two classes of carbohydrate binding proteins: lectins and antibodies specific for carbohydrate epitopes. Specificity of lectin staining was verified using carbohydrate ligands to block lectin interaction, glycohydrolases to cleave specific sugar residues that are receptors for these proteins, and periodate oxidation to destroy susceptible sugar residues. Specific antibodies were used to identify various tissue types and germ layers present in the 12- and 28-day differentiating embryoid bodies. Results from 12 and 28-day differentiated embryoid bodies were compared to determine changes over time. A slight increase in the sialylation of α-GalNAc was seen between 12 and 28 days of differentiation due to the presence of sialyl Tn and/or other sialylated α-GalNAc residues. Increases were also observed in GalNAc, the T antigen (Gal β1,3 GalNAc), and difucosylated LacNAc residues during this time interval. Additionally, some distinct differences in the pattern of lectin staining between 12 and 28 days were observed. Not unexpectedly, the presence of most differentiated cell-types increased during this time period with the exception of neural progenitors, which decreased. Undifferentiated cells, which were prevalent in the 12-day EBs, were undetectable after 28 days. We conclude that several changes in glycosylation occurred during the differentiation of embryonic stem cells, and that these changes may play a role in embryonic development. Lectin abbreviations can be found in Table 1.  相似文献   

11.
The Palauan archipelago contains one of the most ecologically diverse coral reef systems in the Indo-Pacific that was as attractive for humans prehistorically as it is today. New evidence is emerging that during the past few thousand years there has been increasing exploitation of coral reef resources, particularly finfish and mollusks, leading to a decline in taxa numbers, richness, and diversity in various locales. This paper examines the historical interactions between human populations and coral reef ecologies in Palau by combining known archaeological data and results from modern biological data of different reef fauna. The integration of these data sources provides a framework for attempting to explain variations in taxa composition between islands in the archipelago and how this may relate to human exploitation or other phenomena through time. By using this perspective to link past events with present-day conditions, we can gain a better sense of the extent to which anthropogenic changes may have affected island environments in western Micronesia during the Late Holocene. The study also illustrates the many difficulties researchers face in attempting to synthesize and explain past and present human predation behavior when using disparate sources of data.
S. M. FitzpatrickEmail:
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14.
The deep dichotomy of archaea and bacteria is evident in many basic traits including ribosomal protein composition, membrane lipid synthesis, cell wall constituents, and flagellar composition. Here we explore that deep dichotomy further by examining the distribution of genes for the synthesis of the central carriers of one carbon units, tetrahydrofolate (H4F) and tetrahydromethanopterin (H4MPT), in bacteria and archaea. The enzymes underlying those distinct biosynthetic routes are broadly unrelated across the bacterial–archaeal divide, indicating that the corresponding pathways arose independently. That deep divergence in one carbon metabolism is mirrored in the structurally unrelated enzymes and different organic cofactors that methanogens (archaea) and acetogens (bacteria) use to perform methyl synthesis in their H4F- and H4MPT-dependent versions, respectively, of the acetyl-CoA pathway. By contrast, acetyl synthesis in the acetyl-CoA pathway — from a methyl group, CO2 and reduced ferredoxin — is simpler, uniform and conserved across acetogens and methanogens, and involves only transition metals as catalysts. The data suggest that the acetyl-CoA pathway, while being the most ancient of known CO2 assimilation pathways, reflects two phases in early evolution: an ancient phase in a geochemically confined and non-free-living universal common ancestor, in which acetyl thioester synthesis proceeded spontaneously with the help of geochemically supplied methyl groups, and a later phase that reflects the primordial divergence of the bacterial and archaeal stem groups, which independently invented genetically-encoded means to synthesize methyl groups via enzymatic reactions. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.  相似文献   

15.
Tree-ring (TR) observations provide important data on long-term forest dynamics and their underlying ecophysiological mechanisms. To elucidate the seasonal link between photosynthetic carbon acquisition and TR growth, we analyzed the correlation between observed TR data (carbon sink) and model-estimated net primary production (NPP; carbon source). Temporal trends of the TR–NPP correlation over the last century were also analyzed to identify influences of past climate changes. We used TR data from Picea glehnii at seven sites on Hokkaido Island, Japan, which were obtained from the International Tree-Ring Data Bank. At each site, NPP was estimated using the Vegetation Integrative Simulator for Trace gases model, which was driven by long-term (1900–2010) meteorological data. Site-mean tree-ring width index (TRWI) chronologies were analyzed to reveal any relationship with the current or previous year’s annual or monthly NPP. We found moderate to strong correlations between TRWIs and model-estimated monthly NPP from April to June, especially in June of the current year, but no clear spatial trend was observed. During the twentieth century, the TRWI–NPP correlation increased for February, March, April, and July NPP of the current year and for October NPP of the previous year. Ecophysiologically, the period from April to June corresponds to the season when tree cambial cells are formed in the study area. Our findings suggest that photosynthate produced during this cambial growth season is allocated to stem growth and that this source allocation season has become longer due to past environmental changes.  相似文献   

16.
Taking advantage of a marked yearly fluctuation in the number of estrous females, I studied the differences in mating success between troop males and non-troop males in an unprovisioned group of Japanese macaques. Fluctuation in the defendability of estrous females by troop males, as predicted by the operational sex ratio (the number of estrous females per troop male), strongly affected the mating with ejaculation (successful mating) per observation day of both troop and non-troop males. When operational sex ratio was low, troop males monopolized successful mating inside the troop. No successful mating of non-troop males was observed inside the troop. In contrast, both troop and non-troop males were able to mate often inside the troop when operational sex ratio was high. These findings suggest that troop males obtained the benefit of secured successful mating in the troop because troop males could mate successfully even in mating seasons with a low operational sex ratio, and the chance of successful mating for non-troop males will increase as the ability of troop males to monopolize estrous females decreases.  相似文献   

17.
In the coastal area of Mikawa Bay, central Japan, specimens of the female Japanese eel Anguilla japonica could be divided into two groups according to the degree of swim bladder development. In one case, they were undeveloped, and in the other, they were highly developed with large rete mirabile, thick submucosa, and a well-developed gas gland. The morphology of the swim bladder in the latter group was comparable with that in the artificially fully maturated eel. The specimens with an undeveloped swim bladder were caught during all months, although their number was small. The specimens with a highly developed swim bladder were most abundant in November and December. During these months, catch of the specimens also increased sharply, by more than 10 fold compared to that in other months. These observations indicate that most of the eel appearing in coastal Mikawa Bay from October to January have a highly developed swim bladder adapted for a deep-sea environment. It was also conjectured that these specimens most likely migrated from rivers feeding into Mikawa Bay, toward spawning grounds in the open sea, and that this occurred after development of their swim bladders was completed. Actually, the specimens caught in the upstream of the Toyo River feeding into Mikawa Bay from late August to early October already had highly developed swim bladders.  相似文献   

18.
Pollen analytical results from a littoral profile taken in Lake Constance compared with pollen profiles from small kettle holes nearby form the basis for conclusions concerning human population density, the economy and environment from the Neolithic period to the Middle Ages. Early Neolithic human impact is implicated in a lime decline and also the expansion of beech. The late Neolithic lakeshore settlements caused a decline of elm, beech and lime and, by shifting cultivation, considerably changed the forest cover. The settlements were abandoned after less than 100 years. There were long periods without distinct human impact in the middle and towards the end of the late Neolithic period. Since at least the Late Bronze Age there has been permanent habitation in the region. Human impact was greatest in the High Medieval period and later, and was also substantial in the late La Tène and Roman periods. Distinct declines in human impact can be observed between the La Tène and Roman periods and in the Migration and Merovingian periods. In these intervals, open land and grazed oak forest were replaced by birch and later on by beech forests. The decreases in human impact are not of the same intensity in all diagrams.  相似文献   

19.
Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. Large forest wildfires and areas burned in them have continued to increase over recent decades, with most of the increase in lightning-ignited fires. Northern US Rockies forests dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern US forests has rapidly increased over the last two decades. Wildfire numbers and burned area are also increasing in non-forest vegetation types. Wildfire activity appears strongly associated with warming and earlier spring snowmelt. Analysis of the drivers of forest wildfire sensitivity to changes in the timing of spring demonstrates that forests at elevations where the historical mean snow-free season ranged between two and four months, with relatively high cumulative warm-season actual evapotranspiration, have been most affected. Increases in large wildfires associated with earlier spring snowmelt scale exponentially with changes in moisture deficit, and moisture deficit changes can explain most of the spatial variability in forest wildfire regime response to the timing of spring.This article is part of the themed issue ‘The interaction of fire and mankind’.  相似文献   

20.
The age‐markers described at the adult acetabulum by Rissech et al. (J Forensic Sci 51 (2006) 213–229) were scored in the Spitalfields collection of skeletons of documented age and sex (N = 161). The purpose of the work was as a contribution to the evaluation of the general utility of these markers for estimating age at death. To this end, their relationship both with age, and with some other factors, was investigated. The latter comprised sex, general tendency toward bone formation in periarticular soft tissue (as measured by the occurrence of diffuse idiopathic skeletal hyperostosis), and occupation (as documented for some of the males). Of the seven Rissech et al. variables, only four were found to show a statistically significant relationship with age. The correlation between a composite score derived from a linear combination of these four variables, and age was similar to or greater than correlations between age and composite scores based on other age indicators reported in the literature for Spitalfields. Male acetabula aged at a greater rate than those of females. There was no relationship with the occurrence of DISH, but for occupation, those in nonmanual professions showed greater acetabular scores‐for‐age than those in manual trades. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

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