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1.
Stature and the pattern of body proportions were investigated in a series of six time-successive Egyptian populations in order to investigate the biological effects on human growth of the development and intensification of agriculture, and the formation of state-level social organization. Univariate analyses of variance were performed to assess differences between the sexes and among various time periods. Significant differences were found both in stature and in raw long bone length measurements between the early semipastoral population and the later intensive agricultural population. The size differences were greater in males than in females. This disparity is suggested to be due to greater male response to poor nutrition in the earlier populations, and with the increasing development of social hierarchy, males were being provisioned preferentially over females. Little change in body shape was found through time, suggesting that all body segments were varying in size in response to environmental and social conditions. The change found in body plan is suggested to be the result of the later groups having a more tropical (Nilotic) form than the preceding populations.  相似文献   

2.
Obstetric selection acts on the female pelvic canal to accommodate the human neonate and contributes to pelvic sexual dimorphism. There is a complex relationship between selection for obstetric sufficiency and for overall body size in humans. The relationship between selective pressures may differ among populations of different body sizes and proportions, as pelvic canal dimensions vary among populations. Size and shape of the pelvic canal in relation to body size and shape were examined using nine skeletal samples (total female n = 57; male n = 84) from diverse geographical regions. Pelvic, vertebral, and lower limb bone measurements were collected. Principal component analyses demonstrate pelvic canal size and shape differences among the samples. Male multivariate variance in pelvic shape is greater than female variance for North and South Africans. High‐latitude samples have larger and broader bodies, and pelvic canals of larger size and, among females, relatively broader medio‐lateral dimensions relative to low‐latitude samples, which tend to display relatively expanded inlet antero‐posterior (A‐P) and posterior canal dimensions. Differences in canal shape exist among samples that are not associated with latitude or body size, suggesting independence of some canal shape characteristics from body size and shape. The South Africans are distinctive with very narrow bodies and small pelvic inlets relative to an elongated lower canal in A‐P and posterior lengths. Variation in pelvic canal geometry among populations is consistent with a high degree of evolvability in the human pelvis. Am J Phys Anthropol 151:88–101, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

3.
4.
Pollen grains characteristic of the local pre-tricolpate, pre-Aptian phase of angiosperm evolution have been recovered from the upper part of the Six Hills Formation in the Dakhla Oasis area, Egypt. Highest abundance (up to 16.5 per cent) and diversity of angiosperm pollen is attained in samples from the Tineida 2 borehole, which also display a remarkable variety of different aperture types for a palynoflora of late Barremian age. Monosulcate, columellate tectates such as Retimonocolpites are most important, but a single trichotomosulcate grain as well as monoporate and inaperturate types that have not been reported from many coeval palynofloras, are also present. The following new taxa are described using same-grain SEM/LM techniques: Tucanopollis annulatus Schrank, sp. nov., Retimonocolpites pennyi Schrank and Mahmoud, sp. nov. and Retiacolpites columellatus Schrank, gen. et sp. nov. Phytogeographic links are closest with palynofloras previously described from the late Barremian of West Africa (Gabon, Congo), that is within the Northern Gondwana or Dicheiropollis etruscus/Afropollis Province.  相似文献   

5.
A histomorphometric study of thin femoral head sections of a skeletal sample from the Dakhleh Oasis, Egypt, dated from circa 36 B.C. to 400 A.D., identified an adult female (Dk31-A1) in her mid-50s with a high percentage resorption surface with tunneling resorption as is typically found in hyperparathyroidism. Five static histomorphometric bone parameters were measured with the following results for this individual: 1) mean wall thickness, 41.94 micron, 2) trabecular bone volume, 18.54%, 3) surface volume, 4,070 mm2/cm3, 4) mean trabecular diameter, 132 microns, and 5) total resorption surface, 12.31%. The overall histomorphometric features and differential diagnosis support the diagnosis of hyperparathyroidism. We conclude that histomorphometry of dried bone, particularly in this case where preservation is ideal, is a valuable investigative technique for paleopathology.  相似文献   

6.
The European cave bear evolved during the Middle Pleistocene and adapted to mountain environments. Earlier workers have described the cave bear as a robust bear. In this study the cave bears limb bone morphology is compared to the limb bone morphology of extant bears. Body mass estimates for the cave bear are made both based on different limb bone characters and based on dental and cranial characters. The shafts are wider in the cave bear limb bones than in the extant bear limb bones, and consequently the shaft widths give higher weight estimates to the cave bear than the other dimensions. The widened shafts are suggested to be a special adaptation (of presently unknown significance) rather than an indicator of an increased body mass.  相似文献   

7.
The Neolithic site at Hidden Valley, Farafra Oasis, Egypt (6028±150 – 5163±374 cal B. C.) on the shores of a playa (dry lake basin in the desert), yielded a large quantity of carbonized plant remains from post-holes, hearths, querns and a corridor. The plant remains could have become carbonised during food preparation, or when fuel included seeds. Rich and diverse floras were retrieved from 40 soil samples, in all 534 seeds, grains, spikelets, culm fragments and leaflet fragments which were attributed to 30 taxa in the flora of Egypt. Wild grasses from almost all samples represent 83% of the plant remains. Quantitative correlation between plants remains and archaeological contexts is discussed. The highest density of plant remains was recorded from pot-holes (in which pots were stood), while sediments recovered near querns show the lowest. The economy of the site was apparently based mainly on herding associated with the gathering of grasses which suggests that the climate at Farafra during the middle Holocene (6077–4511 cal B. C.) was wetter than today's, with winter and summer rainfall. A reconstruction of the vegetation around the site comprises reed plant cover, aquatic and wetland plants and desert savanna. Received March 8, 2001 / Accepted June, 2001  相似文献   

8.
Studies of infant feeding and weaning patterns in past populations that rely on a cross-sectional approach must make the assumption that no infant mortality bias exists. Previous investigations of infant weaning patterns at the Dakhleh Oasis, Egypt, relied on cross-sectional isotope data. In this study, we re-examine this weaning pattern, using a simulated longitudinal approach, which does not require any assumptions regarding potential infant mortality biases. This involves examining the dental isotopic signatures of individuals who survived the weaning process. Stable isotope signatures from juveniles and adults (102 individuals, 297 teeth) were examined to reconstruct the weaning history of those that survived the weaning process. Both deciduous and permanent teeth were sampled. Homogenized enamel and dentin samples were isolated from each tooth and analyzed for delta(13)C(ap) and delta(18)O(ap) from the enamel and delta(15)N(coll) and delta(13)C(coll) from dentin collagen. We investigate differences between in utero versus postbirth, preweaning versus postweaning, and juvenile versus adult stable isotope values as reflected in the dentition. A random permutation procedure was used to test for statistically significant differences in stable isotope values between tooth types. Statistically significant differences were observed in all stable isotopes between permanent and deciduous teeth, and between early and later forming permanent teeth in delta(13)C(ap) and delta(15)N(coll) isotopes. These results indicate dietary change between in utero and postbirth, and changes occurring during the weaning period. These results provide a more comprehensive picture of infant weaning practices at Kellis and provide further support that complete weaning occurred by 3 years of age.  相似文献   

9.
The application of indicator species analysis has proved useful in classifying stands into groupings coinciding with topographic variations. 41 indicator pseudo-species are identified in the vegetation along a phytosociological gradient: some are characteristic of specific habitats, and the others indicate transition between groups of habitats.The use of qualitative estimations (transformed density records) in multivariate analysis in the present study indicates that they may be more preferable than quantitative estimations, because of their easy and fast recording in the field, and the less comprehensive computations, while yielding precise results.The X-axis of the reciprocal averaging ordination is related to the salinity and fertility gradients, while the Y-axis reflects soil texture.The phytosociological gradients of the canonical variate axes reflect essentially contrasts between groups of species, each correlated with one or the other of the environmental gradients.Comparing the results obtained by the two ordination methods (reciprocal averaging and canonical variates) we find that the first method detects the overall phytosociological changes along strong environmental gradients which would be helpful in studying large surveys. On the other hand, the second technique, which is mainly predictive, is more sensitive to changes within both the phytosociological and environmental gradients and can detect the impact of these changes on the overall variance of each gradient.Nomenclature follows Täckholm (1964).The authors are grateful to Dr J. Jeffers and Mr and Mrs P. Howard of the Institute of Terrestrial Ecology, England, for their help with applying the multivariate techniques to the vegetation data.  相似文献   

10.
Limited data are available on the concentration of metals in sediments in the Western Harbour of Alexandria. The most comprehensive record is from a survey conducted more than a decade ago. Industrial and human activities in and around this area have increased dramatically in the last 20 years. The purpose of this study was to determine the concentrations of heavy metals in surfacial bottom sediments of the harbor, to assess their potential biological effects and to identify their possible sources. Sediment samples from 21 stations throughout the harbor were analyzed for grain size, total organic carbon content (TOC), and metals (Al, As, Ba, Be, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Se, Sn, V, and Zn) to assess the extent of contamination in the area. The results indicated that concentrations of metals in the sediments varied widely depending on the location. High levels of metals were observed in the Arsenal Basin and the outfall area of El Mahmoudiya Canal in the inner harbor. The concentrations of metals were found to be higher than those recorded in the previous study. However, with some exceptions, most of the changes in the metal concentrations could be accounted for by the variations in aluminum, which represents the variations in mineralogy and grain size, indicating that the majority of the metals were of “natural” origin. The present data were also compared with results from other areas.  相似文献   

11.
Representatives of the various Stages (1–9) in the metamorphosis and short adult life of the brook lamprey, Lampetra planeri , were used to provide quantitative data to describe the pattern of changes that take place during this period of the life cycle. During the transformation of the oral hood into an oral disc, this ventral region of the snout first declines in length before increasing markedly. The branchial region declines in length and remains relatively smaller than in the ammocoete, a feature probably correlated with the concomitant internal changes in the pharynx which permit a change from a unidirectional to a tidal respiratory flow. The eye increases in size only through the initial Stages (1–5). The main period of fin enlargement occurs rather later in metamorphosis than the above changes.
During maturation the two initially separate dorsal fins increase further in height and eventually become separated only by a notch. Differences between the two sexes are found in the relative size of the disc and fins, the larger structures of the male probably being related to their greater activity in spawning behaviour. Measurements on metamorphosed L. fluviatilis confirm that in this species the eye and disc are relatively larger than in L. planeri. Data are presented which illustrate that in collections taken during the metamorphosis of both species the males are smaller and slightly more numerous than the females and that transformation is initiated at a longer length in L. planeri than in L. fluviatilis .  相似文献   

12.
Fadl  Ezzat M. 《Mycopathologia》1997,140(2):99-103
Using the seed-plate technique, 18 different isolates of Fusarium moniliforme were isolated on pentachloronitrobenzene (PCNB) agar medium from 18 samples of a local variety of corn collected from locations in Minia Governorate. The isolates of F moniliforme were screened for their ability to produce fumonisins on polished rice grains using the solid state fermentation technique. Based on thin layer chromatographic (TLC) analyses using silica gel plates, 14 of the 18 isolates tested produced FB1 and FB2 with R f (0.17) and (0.24), respectively. Concentration of FB1 was estimated using high performance liquid chromatography (HPLC). Production of FB1 by the 14 isolates of F. moniliforme tested ranged from 69 to 4495 ppm indicating that mouldy corn may represent a health hazard to consumers. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

13.
Maastrichtian-early Paleocene foraminiferal palaeobathymetry, palaeodiversity and vertical facies changes of Gebel El Sharawna, south Luxor, Egypt have been studied to determine the depositional sequences, their relationships to global records and/or tectonic signatures. Five benthonic assemblages are recorded and replicated in the present study reflect fluctuation in palaeo-water depth from restricted marginal marine to outer shelf palaeoenvironments. Four sequence boundaries that coincide with the Campanian/Maastrichtian, intra-early Maastrichtian, Early/Late Maastrichtian, Cretaceous/Palaeogene (K/Pg) and intra-Danian were recognized based upon sharp vertical facies changes, foraminiferal assemblage changes, hiatuses, mineral hard ground and reworking. The K/Pg unconformity reveals an unexpected ca. 4.2 Myr time gap as indicated by the absence of the CF2 Zone through lower part of the P1c Zone. It is easily distinguished in the field by conglomeration and winnowing of phosphate and glauconite in the lower Paleocene. These sequence boundaries defined five third-order depositional sequences mainly developed as the result of the eustatic sea-level changes, coupled with the Arabian–Nubian shield tectonic uplift at the southern edge of the Tethys Ocean.  相似文献   

14.
The phenotypic expression of adult body size and shape results from synergistic interactions between hereditary factors and environmental conditions experienced during growth. Variation in body size and shape occurs even in genetically relatively homogeneous groups, due to different occurrence, duration, and timing of growth insults. Understanding the causes and patterns of intrapopulation variation can foster meaningful information on early life conditions in living and past populations. This study assesses the pattern of biological variation in body size and shape attributable to sex and social status in a medieval Italian population. The sample includes 52 (20 female, 32 male) adult individuals from the medieval population of Trino Vercellese, Italy. Differences in element size and overall body size (skeletal height and body mass) were assessed through Monte Carlo methods, while univariate non-parametric tests and Principal Component Analysis (PCA) were employed to examine segmental and overall body proportions. Discriminant Analysis was employed to determine the predictive value of individual skeletal elements for social status in the population. Our results highlight a distinct pattern in body size and shape variation in relation to status and sex. Male subsamples exhibit significant postcranial variation in body size, while female subsamples express smaller, nonsignificant differences. The analysis of segmental proportions highlighted differences in trunk/lower limb proportions between different status samples, and PCA indicated that in terms of purely morphological variation high status males were distinct from all other groups. The pattern observed likely resulted from a combination of biological factors and cultural practices.  相似文献   

15.
Summary A sequence of late Pliocene sediments (Qaret El-Muluk Formation) covers large areas within Wadi El-Natrun depression; at the western periphery of the Nile Delta. The exposed sequence is composed of friable sands. mudstones, shales and minor limestones with combined total thickness of approximately 50 m. The fossil content consists of fresh and brackish water elements; charophytes, ostracods, gastropods, oysters and benthonic foraminifera. Planktonic forams which suggest marine influence have been also recorded. Terrestrial and aquatic continental vertebrate fauna includes mammals, reptiles, fish and aves. Several subtypes of ichthyoliths have been discovered in this study. Both lithological and paleontological data testify to a depositional environment which belongs to a marginal region where fluvial and marine deposition meet in shallow brackish lagoons. The sediments display changes from channelled fluvial sands to deltaic interbedded sands and mudstones to lagoonal shales and limestones to lacustrine chara limestones. Vertical stacking of facies is indicative of a series of transgressive-regressive events. The transgression brought shallow lagoonal conditions to the area. The transgressions were incomplete due to high rate of fluvial input. The lagoon dried up intermittently and calcretes and red brown soils were formed. Each regression is indicated by river generated clastic influx. During periods of active fluvial input, fluvial sediments prograded lagoonward. The clastic material was probably a mixture of reworked detritus from older sediments. An admixture of first cycle material from the basement rocks of the Red Sea hills cannot be ruled out. The diversity of provenance argues for several channels of a large river which existed during the late Pliocene.  相似文献   

16.
Based on microfacies analyses and sedimentological data, 17 facies are identified within the Middle Miocene carbonates at Siwa Oasis in the northern Western Desert of Egypt. These facies are attributed to five main facies belts. Within these facies and facies belts, five foraminiferal assemblages are recognized. A depositional model relates the reported facies and biofacies to a down-dip depositional profile of an inner to middle carbonate ramp. The facies of the peritidal to restricted lagoon (facies belt 1) and the less-restricted lagoon (facies belt 2) were deposited in the inner ramp behind the barrier/beach shoal facies belt 3. Basinward, lime mudstone of facies belts 4 and 5 accumulated in a proximal to distal middle ramp, respectively. The depositional evolution involved three stages, which are strongly controlled by tectonics and eustatic sea-level changes. The first stage comprises the transgressive Lower Miocene clastic-dominated fluvial facies of the Moghra Formation. The second stage heralds the deposition of the Langhian inner-ramp carbonate and shale facies of the basal Oasis Member of the Marmarica Formation under a relatively high stand of sea level, constrained clastic influx and climate warming. The final stage is represented by Langhian to Serravallian mid-ramp carbonate-dominated facies of the Siwa Escarpment and El Diffa Plateau members under fluctuating sea level, and a westward restriction in clastic supply and water turbidity.  相似文献   

17.
Traditionally a few limb proportions or total limb lengths have been regarded as indicative of peak running velocity. This is due to physical principles (inferred in- and outvelocities around the joints, stride lengths) and also the observation that fast-moving animals tend to share a number of purported key features which are either absent or not developed to near the same extent in slower moving forms. Previous studies have shown hind limb length and metatarsus/femur ratio to be correlated significantly, albeit modestly with running speed. These studies have nearly all been bivariate analyses. Based on the physical principles, there is reason to suppose that more variables than just m/f ratio could be important as adaptations for fast locomotion, and also that bivariate analyses are too simple. In this study a sample of 76 running mammals was used, with running speeds taken from literature. A number of osteological parameters were discovered to covary significantly with peak running speed, albeit only modestly. Using the information from phylogeny reduced all correlations, often significantly so. Multivariate analyses resulted in markedly higher correlation coefficients. Animals probably do not optimize their anatomy for the purpose of running very fast, which occurs only on rare occasions, but for reducing costs of locomotion.  © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society , 2002, 136 , 685–714.  相似文献   

18.
During locomotion, mammalian limb postures are influenced by many factors including the animal's limb length and body mass. Polk (2002) compared the gait of similar-sized cercopithecine monkeys that differed limb proportions and found that longer-limbed monkeys usually adopt more extended joint postures than shorter-limbed monkeys in order to moderate their joint moments. Studies of primates as well as non-primate mammals that vary in body mass have demonstrated that larger animals use more extended limb postures than smaller animals. Such extended postures in larger animals increase the extensor muscle mechanical advantage and allow postures to be maintained with relatively less muscular effort (Polk, 2002; Biewener 1989). The results of these previous studies are used here to address two anthropological questions. The first concerns the postural effects of body mass and limb proportion differences between australopithecines and members of the genus Homo. That is, H. erectus and later hominins all have larger body mass and longer legs than australopithecines, and these anatomical differences suggest that Homo probably used more extended postures and probably required relatively less muscular force to resist gravity than the smaller and shorter-limbed australopithecines. The second question investigates how animals with similar size but different limb proportions differ in locomotor performance. The effects of limb proportions on gait are relevant to inferring postural and locomotor differences between Neanderthals and modern Homo sapiens which differ in their crural indices and relative limb length. This study demonstrates that primates with relatively long limbs achieve higher walking speeds while using lower stride frequencies and lower angular excursions than shorter-limbed monkeys, and these kinematic differences may allow longer-limbed taxa to locomote more efficiently than shorter-limbed species of similar mass. Such differences may also have characterized the gait of Homo sapiens in comparison to Neanderthals, but more experimental data on humans that vary in limb proportions are necessary in order to evaluate this question more thoroughly.  相似文献   

19.
Forty six species and two sterile fungi and yeast species were isolated from samples collected both indoors and outdoors of coastal buildings located in an Egyptian coastal city. Twenty flats from ten buildings were investigated; children living in these buildings have been reported to suffer from respiratory illnesses. Samples were taken using a New Brunswick sampler (model STA-101) operating for 3.0 min at a flow rate of 6.0 l/min. Most of the species isolated have been associated with symptoms of respiratory allergies. Indoors the total culturable fungal count was 1548 CFU/m3; outdoors, it was 1452 CFU/m3. Indoor values of culturable fungal count, total spores count and ergosterol content ranged from 52 to 124 CFU/m3, 100 to 400 spore/m3 and 5 to 27.7 mg/m3, respectively, whereas outdoor levels typically varied between 25 and 222 CFU/m3, 110 and 900 spore/m3 and 3.3 and 67.2 mg/m3, respectively. The maxima for these parameters were detected indoors in house no. 6 and outdoors, outside of house no. 7. The most abundant species were primarily mitosporic (2832 CFU/m3). The most frequent species in both the indoor and outdoor samples were Cladosporium cladosporioides followed by Alternaria alternata and Penicillium chrysogenum,with inside:outside ratios of 1.4, 1.8 and 1.9, respectively. The patterns of fungal abundance were influenced to some extent by changes in the relative humidity and temperature. Other factors, such as type of culture media, rate of sedimentation, size, survival rates of spore and species competition,also affected fungal counts and should be taken into consideration during any analysis of bioaerosol data.  相似文献   

20.
Variation in femoral and tibial diaphyseal shape is used as an indicator of adaptation to patterns of terrestrial mobility. Recent experimentation has implied that lower limb diaphyseal shape may be primarily influenced by lower limb length, and less so by mobility patterns. If valid, this would, at most, render previous interpretations of mobility patterns based on analyses of diaphyseal shape questionable, and, at least, require additional standardization that considers the influence of limb length. Although the consequences could be profound, this implication has yet to be directly tested. Additionally, the influence of body breadth on tibial shape (and to a lesser extent femoral shape) remains uncertain. Tibial and femoral cross‐sectional midshaft shape measurements, taken from nine Pleistocene and Holocene skeletal populations, were compared against lower limb length, limb segment length, and bi‐iliac breadth. Generally, limb length and limb segment length do not significantly influence femoral or tibial midshaft shape. After controlling for body mass greater bi‐iliac breadth is associated with a relative mediolateral strengthening of the femoral midshaft, while the influence of a wider body shape (BIB/length) is associated with a relative M‐L strengthening of the tibia and femur of males, and the tibia of females. We conclude that; (1) mechanical interpretations of lower limb diaphyseal shape are most parsimonious due to the lack of evidence for a consistent relationship between segment length and shape; however, (2) further work is required to investigate the influence of bi‐iliac breadth on both femoral and tibial midshaft shape. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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