Concordance of cranial and dental morphological traits and evidence for endogamy in ancient Egypt

A biological affinities study based on frequencies of cranial nonmetric traits in skeletal samples from three cemeteries at predynastic Naqada, Egypt, confirms the results of a recent nonmetric dental morphological analysis. Both cranial and dental traits analyses indicate that the individuals buried in a cemetery characterized archaeologically as high status are significantly different from individuals buried in two other, apparently nonelite cemeteries and that the nonelite samples are not significantly different from each other. A comparison with neighbouring Nile Valley skeletal samples suggests that the high status cemetery represents an endogamous ruling or elite segment of the local population at Naqada, which is more closely related to populations in northern Nubia than to neighbouring populations in southern Egypt. © 1996 Wiley-Liss, Inc.     

Who were the ancient Egyptians? Dental affinities among Neolithic through postdynastic peoples

Qualitative and quantitative methods are employed to describe and compare up to 36 dental morphological variants in 15 Neolithic through Roman-period Egyptian samples. Trait frequencies are determined, and phenetic affinities are calculated using the mean measure of divergence and Mahalanobis D2 statistics for discrete traits; the most important traits in generating this intersample variation are identified with correspondence analysis. Assuming that the samples are representative of the populations from which they derive, and that phenetic similarity provides an estimate of genetic relatedness, these affinities are suggestive of overall population continuity. That is, other than a few outliers exhibiting extreme frequencies of nine influential traits, the dental samples appear to be largely homogenous and can be characterized as having morphologically simple, mass-reduced teeth. These findings are contrasted with those resulting from previous skeletal and other studies, and are used to appraise the viability of five Egyptian peopling scenarios. Specifically, affinities among the 15 time-successive samples suggest that: 1) there may be a connection between Neolithic and subsequent predynastic Egyptians, 2) predynastic Badarian and Naqada peoples may be closely related, 3) the dynastic period is likely an indigenous continuation of the Naqada culture, 4) there is support for overall biological uniformity through the dynastic period, and 5) this uniformity may continue into postdynastic times.     

The Bronze-Age Harappans: A re-examination of the skulls in the context of the population concept

The biometric data on 72 usable adult skulls excavated at Harappa and dated ca. 2500-1700 bc have been re-examined in the light of the genetic concept of “population.” The original study of the material considered separately and independently the various samples from locally differentiated cultural deposits, Cemetery R37, Area G, Cemetery H, etc., and used the typologic concept of racial analysis, a traditional method now sterile. One of the major findings of the study, postulating hypothetical original races, was that a varying proportions of different racial “types” constituted each sample. The present analysis is designed, first, to identify the particular population responsible for the growth of the true Harappan culture and, secondly, to define some selected physical characters of the population. Fifteen variables provided statistical evidence that the pooled remains of Cemetery R37 and Area G can be considered as a sufficiently homogeneous Harappan population. Further, in the absence of statistically significant differences in separate measurements, the entire material may be regarded as representing the Bronze-Age Harappans. Accordingly, some selected cranio-facial features of the population have been described.     

Infectious disease among enslaved African Americans at Eaton's Estate, Warren County, North Carolina, ca. 1830-1850

The skeletal remains of 17 people buried in the Eaton Ferry Cemetery in northern North Carolina provide a means of examining health and infectious disease experience in the XIX century South. The cemetery appears to contain the remains of African Americans enslaved on the Eaton family estate from approximately 1830-1850, and thus offers a window into the biological impacts of North American slavery in the years preceding the Civil War. The sample includes the remains of six infants, one child, and one young and nine mature adults (five men, four women, and one unknown). Skeletal indices used to characterize health and disease in the Eaton Ferry sample include dental caries, antemortem tooth loss, enamel hypoplasia, porotic hyperostosis, periosteal lesions, lytic lesions, and stature. These indicators reveal a cumulative picture of compromised health, including high rates of dental disease, childhood growth disruption, and infectious disease. Specific diseases identified in the sample include tuberculosis and congenital syphilis. Findings support previous research on the health impacts of slavery, which has shown that infants and children were the most negatively impacted segment of the enslaved African American population.     

Dental caries and antemortem tooth loss in the Northern Peten area,Mexico: a biocultural perspective on social status differences among the Classic Maya

Dental caries and antemortem tooth loss (AMTL) are investigated in a Classic Maya sample obtained from the sites of Calakmul, Dzibanché, and Kohunlich (Mexico). This study aims at assessing the effect that sex and social status had on the prevalence of oral pathologies. The lack of a direct relationship between caries, AMTL, and age-at-death led us to interpret the results in terms of the biological, socioeconomic, and behavioral conditions prevailing in these ancient Maya settlements. Benefits related to sex and social status are evident in the frequency of carious lesions, which appear less frequently in elite males than in low-status individuals of both sexes and in elite females. Individuals from problematic mortuary contexts and isolated bone assemblages, who could not be ascribed to any status group, showed the highest rates of caries. Sex discrimination in dietary preferences appears in the elite sample, while the homogeneity encountered between sexes in the low-status segment suggests a more uniform access to resources. Tooth loss clearly distinguishes elite individuals from commoners, regardless of sex, with the former bearing a much higher rate of loss. In individuals from the undefined mortuary assemblages and sacrificial contexts, it was even more pronounced than in the other groups, although its interpretation is problematic due to a lack of associated funerary data. The overall evidence from oral pathologies is interpreted to be the result of deficient oral hygiene coupled with a softer and more refined diet in the high-status population, particularly males. Whereas elite males' subsistence was apparently based more on animal proteins and relatively soft and refined foods, a diet relying on carbohydrates may account for the observed rate of oral pathologies in elite females and commoners.     

THE IMAGINED 'CONSUMER DEMOCRACY' AND ELITE (RE)PRODUCTION IN YEMEN

In the republican state which emerged in North Yemen after the 1962 revolution the new ruling elite, which forms the core of the nouveaux riches , buttresses its claim to high status by wealth display and conspicuous consumption. Depending on regional variation, the old elite's acquiescence in or rejection of new consumption practices expresses respectively either the maintenance of an elevated social position or a protest against what is considered a corrupt social order. Whereas consumption has led to a degree of homogeneity among the affluent old and the new elite of San'a, the old elite as a whole has become more fragmented. In light of Bourdieu's Distinction , this article argues that 'taste', generated by class-related incorporated dispositions, may manifest itself in practices ranging from lavish consumption to renunciation. Consumer choice must be explored in relation both to moral schemes and to the pursuit of social pre-eminence.     

What makes an endurance athlete world-class? Not simply a physiological conundrum

Inter-individual variation in endurance performance capacity is a characteristic, not only of the general population, but also in trained athletes. The ability of sport scientists to predict which athletes amongst an elite group will become world-class is limited. We do not fully understand the interactions between biological factors, training, recovery and competitive performance. Assessment methods and interpretation of results do not take into account the facts that most research is not done on elite athletes and performances of world-class endurance athletes cannot be attributed to aerobic capacity alone. Many lines of evidence suggest that there is a limit to adaptation in aerobic capacity. Recent advances in molecular biology and genetics should be harnessed by exercise biologists in conjunction with previously used physiological, histological and biochemical techniques to study elite athletes and their responses to different training and recovery regimens. Technological advances should be harnessed to study world-class athletes to determine optimal training and competition strategies. In summary, it is likely that multiple factors are essential contributors to world-class endurance performance and that it is only by using a multidisciplinary approach that we will come closer to solving the conundrum: 'What makes an endurance athlete world class?'     

Elite controllers with low to absent effector CD8+ T cell responses maintain highly functional, broadly directed central memory responses

Analyses of the breadth and specificity of virus-specific CD8(+) T cell responses associated with control of HIV have largely relied on measurement of cytokine secretion by effector T cells. These have resulted in the identification of HIV elite controllers with low or absent responses in which non-T-cell mechanisms of control have been suggested. However, successful control of HIV infection may be associated with central memory T cells, which have not been consistently examined in these individuals. Gag-specific T cells were characterized using a peptide-based cultured enzyme-linked immunosorbent spot assay (ELISpot). Peripheral blood mononuclear cells from HIV elite controllers (n = 10), progressors (n = 12), and antiretroviral-treated individuals (n = 9) were cultured with overlapping peptides for 12 days. Specificity was assessed by tetramer staining, functional features of expanded cells were assessed by cytokine secretion, and virus inhibition and phenotypic characteristics were assessed by cell sorting and coculture assays. After peptide stimulation, elite controllers showed a greater number of previously undetectable (new) responses compared to progressors (P = 0.0008). These responses were highly polyfunctional, with 64.5% of responses having 3 to 5 functions. Expandable epitope-specific CD8(+) T cells from elite controllers had strong virus inhibitory capacity and predominantly displayed a central memory phenotype. These data indicate that elite controllers with minimal T cell responses harbor a highly functional, broadly directed central memory T cell population that is capable of suppressing HIV in vitro. Comprehensive examination of this cell population could provide insight into the immune responses associated with successful containment of viremia.     

Interpretation of thermal perturbation spectra of proteins.

The thermal perturbation difference spectrum of reduced lysozyme has a long wave length extremum at 304 nm at pH 6.15 and a very small extremum at 306 nm at pH 1.5. These results differ from those of Leach & Smith (1972), which showed an extremum at 293 nm, the same as for model tryptophyl compounds. Our result may arise from a conformational difference between the two sample temperatures. The interpretation of thermal perturbation spectra of proteins is discussed. Contributions from thermally induced concentration differences, buried chromophores, and chromophores in crevices are considered in the interpretation of the thermal perturbation spectrum of bovine serum albumin. It is suggested that chromophores in pauci-aqueous crevices may appear buried toward thermal perturbation spectroscopy but accessible toward solvent perturbation and chemical reagents.     

沣西新城曹家寨清代墓地古人口学初步研究

曹家寨墓地是一处位于陕西西咸新区沣西新城的清代平民墓地,文章通过体质人类学和古人口学研究方法,结合历史文献,对曹家寨墓地的人口结构进行了初步分析。结果表明,沣西新城曹家寨清代居民的性别比为117.5,男性远多于女性,可能与清代盛行的“溺女婴”风俗有关。两性的死亡高峰皆在中年期,但生育行为使得女性壮年期的死亡率是男性的2倍多,有更多的男性居民活到了老年期,表明男性个体有相对更长的寿命。墓地人骨的埋葬方式和迁葬行为,反映了清代一夫一妻多妾的婚姻形式以及平民阶层个体家庭为主的家庭结构。     

Mitochondrial haplogroup T is negatively associated with the status of elite endurance athlete

Mitochondrial function is absolutely necessary to supply the energy required for muscles, and germ line mutations in mitochondrial genes have been related with impaired cardiac function and exercise intolerance. In addition, alleles at several polymorphic sites in mtDNA define nine common haplogroups, and some of these haplogroups have been implicated in the risk of developing several diseases. In this study, we analysed the association between mtHaplogroups and the capacity to reach the status of elite endurance athlete. DNA was obtained from blood leukocytes of 95 Spanish elite endurance athletes and 250 healthy male population controls. We analysed eight mitochondrial polymorphisms and the frequencies were statistically compared between elite athletes and controls. Haplogroup T, specifically defined by 13368A, was significantly less frequent among elite endurance athletes (p =0.012, Fisher's exact test). Our study suggests that allele 13368A and mitochondrial haplogroup T might be a marker negatively associated with the status of elite endurance athlete. This mitochondrial variant could be related with a lower capacity to respond to endurance training, through unknown mechanisms involving a less efficient mitochondrial workload.     

Estimating the age structure of a buried adult population: A new statistical approach applied to archaeological digs in France

Paleodemographers have developed several methods for estimating the age structure of historical populations in absence of civil registration data. Starting from biological indicators alone, they use a reference population of known sex and age to assess the conditional distribution of the biological indicator given age. However, the small amount of data available and the unstable nature of the related statistical problem mean that most methods are disappointing. Using the most reliable reference data possible, we propose a simple statistical method, integrating the maximum amount of information included in the actual data, which quite significantly improves age estimates for a buried population. Here the method is applied to a French cemetery used from Late Antiquity to the end of the Early Middle Ages. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.     

Reduction of CD4+ T cells in vivo does not affect virus load in macaque elite controllers

A small percentage of human immunodeficiency virus (HIV)- and simian immunodeficiency virus (SIV)-infected individuals spontaneously control virus replication. The majority of these elite controllers mount high-frequency virus-specific CD4(+) T cell responses. To evaluate the role these responses might play in viral control, we depleted two elite controller macaques of CD4(+) cells. SIV-specific CD4(+) T cell responses did not return to baseline levels until 8 weeks postdepletion. Viral loads remained stable throughout the experiment, suggesting that SIV-specific CD4(+) T cell responses may not play a direct role in controlling chronic viral replication in these elite controllers.     

Cortical bone maintenance in an historic Afro-American cemetery sample from Cedar Grove, Arkansas

The relocation and analysis of 80 skeletons from the Cedar Grove Cemetery, located in southwest Arkansas, provides an opportunity to examine the level of health and nutrition experienced by Afro-Americans in the post-Reconstruction South (1878-1930). The demographic profile lends support to the interpretation that Cedar Grove participated in the nationwide decline in Afro-American health. The high frequencies of skeletal lesions indicative of dietary deficiencies and infectious disease demonstrate that this was a highly stressed population. For this analysis, adult femoral thin sections (15 females and 14 males) are examined histologically. These data provide support to the assertion that the Cedar Grove population experienced poor health. Measures taken from the sections include cortical thickness, percent cortical area, and mean number of resorption spaces and forming osteons per square millimeter of bone. As a group, they demonstrate low percent cortical area compared with well-nourished normals. They also show high rates of resorption to formation, thereby disrupting the balance necessary for normal cortical bone maintenance. The pattern established for bone porosity in this group is not a function of age but rather is due to other factors, most likely nutrition and disease stress. What may be unique about this group is that males, as well as females, experienced problems with calcium homeostasis and normal maintenance and repair of bone. Taken together, these data support the interpretation that diet and health were substandard in the post-Reconstruction South.     

云南兰坪云南红豆杉种群年龄结构与空间分布格局分析

利用点格局分析法对滇西北兰坪县4个云南红豆杉(Taxus yunnanensis)种群的年龄结构、不同生长阶段空间分布格局及其关联性进行分析。结果表明:(1)林窗与人为干扰影响4个云南红豆杉种群的龄级结构,小林窗的种群呈稳定型;较大林窗的种群呈进展型;群落结构完整未出现林窗和有较大人为干扰的种群年龄结构均呈衰退型,幼苗、幼树与小树个体缺乏,种群存在一定程度的更新困难,林窗的大小是种群更新的重要因素。(2)人为干扰、自然生境与本身生物学特性影响4个种群空间分布格局,种群1整体及其不同生长阶段个体均呈聚集分布;种群2和种群4在小尺度呈聚集分布,而在大尺度上呈随机分布;种群3随着空间尺度增大分布格局表现为聚集→随机→聚集趋势。(3)种群2中幼苗、小树和中树在小尺度下表现为聚集分布,其他尺度下表现为随机分布;种群3的小树阶段聚集分布和随机分布皆有出现,中树与大树在不同尺度上表现为聚集分布;种群4聚集分布的强度随生长阶段的增加在减弱。(4)4个种群各发育阶段间皆呈或接近显著正相关,种内竞争弱,有利于种群维持。     

Iwao’s patchiness regression through the origin: biological importance and efficiency of sampling applications

Iwao’s mean crowding-mean density relation can be treated both as a linear function describing the biological characteristics of a species at a population level, or a regression model fitted to empirical data (Iwao’s patchiness regression). In this latter form its parameters are commonly used to construct sampling plans for insect pests, which are characteristically patchily distributed or overdispersed. It is shown in this paper that modifying both the linear function and statistical model to force the intercept or lower functional limit through the origin results in more intuitive biological interpretation of parameters and better sampling economy. Firstly, forcing the function through the origin has the effect of ensuring that zero crowding occurs when zero individuals occupy a patch. Secondly, it ensures that negative values of the intercept, which do not yield an intuitive biological interpretation, will not arise. It is shown analytically that sequential sampling plans based on regression through the origin should be more efficient compared to plans based on conventional regression. For two overdispersed data sets, through-origin based plans collected a significantly lower sample size during validation than plans based on conventional regression, but the improvement in sampling efficiency was not large enough to be of practical benefit. No difference in sample size was observed when through-origin and conventional regression based plans were validated using underdispersed data. A field researcher wishing to adopt a through-origin form of Iwao’s regression for the biological reasons outlined above can therefore be confident that their sampling strategies will not be affected by doing so.     

Phenotypic plasticity and population differentiation in seeds and seedlings of the grass Anthoxanthum odoratum

Summary Seeds of Anthoxanthum odoratum were transplanted reciprocally between a xeric and a mesic field population that were genetically differentiated in adult traits. In one experiment seeds were reciprocally buried in bags in the soil, in a second experiment seeds were reciprocally sown in small plots. For most traits, site effects were much larger than seed-source effects. Germination, emergence, mortality of buried seed and recruitment were significantly higher at the xeric site than at the mesic site, irrespective of population of origin. Seed dormancy, was significantly higher for seed originating from the mesic than from the xeric population. Seedling recruits originating from the xeric population tended to be larger at both sites. Fecundity of seedling recruits depended on the environment; fecundities of plants growing in the xeric site had more than double the fecundity of plants growing in the mesic site. Phenotypic plasticity rather than population differences determined variation in performance in the seed and seedling stages.     

‘Big data’ from shrinking pathogen populations

Falling costs for genome sequencing and genotyping mean that population genomic data sets are becoming commonplace for a wide variety of species. Once these data are used for the initial tasks of investigating population structure and demographic history, however, is there reason to go back for more? In this issue of Molecular Ecology, Nkhoma et al. (2013) explore the applications of longitudinal genomic diversity data for detecting changes in the prevalence and transmission of the Plasmodium falciparum malaria parasite in South‐East Asia. While this study finds several genetic signatures indicative of reduced disease transmission, other measures, such as short‐term effective population size, geographical population structure and heterozygosity, were not informative. These results indicate the potential contribution of genomic data to the surveillance of small, dynamic populations, whether they are at risk of extinction or targeted for elimination. The interpretation of such data will require close consideration of biological context, however, at both the species and the population level.     

贮藏点深度、大小及基质含水量对花鼠找寻红松种子的影响

2012年8-10月,在黑龙江省伊春市带岭林业局东方红林场,通过人工围栏控制实验,研究了贮藏点深度、大小及基质含水量对花鼠找寻红松种子的影响。发现：(1) 埋藏深度显著影响花鼠对贮藏点的找寻率,埋藏深度为 1 cm 和 2 cm 的找寻率显著高于 4 cm 和 6 cm。(2) 埋藏点大小对花鼠发现种子也有显著影响,埋藏点越大,花鼠发现贮藏点的比例越高。(3) 高的基质含水量利于花鼠找寻贮藏点。结果表明,围栏条件下食物贮藏点深度、大小及基质含水量的改变能显著影响花鼠对贮藏点的找寻。