bluuebunny/crossref_metadata_2025 huggingface dataset:
Histological reconstruction of crown formation times and initial root formation times in a modern human child
Authors: Dean M. C. , Beynon A. D.
Published: February 2006

Previous qualitative studies on root growth in hominoids have suggested that the early stages of root growth in modern human teeth are slower than in great apes, but no quantitative data on root extension rates exist for modern human teeth. The primary objective of this study was to use incremental markings in the crowns of teeth to provide information about crown formation times and early root formation times. This study provides a detailed description of a single unaged child from Spitalfields, London, and presents an internally consistent model of incremental growth in crowns and roots of different teeth of this individual. We describe methods for determining times of initial mineralization in different teeth in the same individual. Scanning electron micrographs of perikymata on tooth surfaces and histological sections of teeth were prepared and analyzed. Total crown formation times were 4.4 years in the lower I1, 4.9 years in the lower 12, and 3.1 years in the upper M1. Average root extension rates indicate that during the first 2 or 3 mm of root growth in the lower permanent incisors and upper first permanent molar the average root extension rate was between 2.9 and 3.8 μm per day. This rate is similar to the rate of enamel extension in the last portion of cervical enamel formed in modern human anterior teeth. These root extension rates are approximately four times slower than similar rates calculated for ape teeth (Beynon et al: Am. J. Phys. Anthropol., 1991), a highly significant difference. The implications of these findings for comparative studies of dental development in early hominids and modern humans are discussed.
Compact bone distribution and biomechanics of early hominid mandibles
Authors: Daegling D. J. , Grine F. E.
Published: February 2006

This investigation explores the effects of compact bone distribution on the biomechanical properties of the postcanine mandibular corpus of the fossil hominid taxa Australopithecus africanus and Paranthropus robustus The mandibles of extant great apes, modern humans, and the fossil hominids are examined by computed tomography (CT), and compact bone contours are used to calculate cross‐sectional biomechanical properties (cortical area, second moments of area, and Bredt's formula for torsional strength). The relative amount of compact bone is comparable in the modern and fossil mandibles, but the mechanical properties of A. africanus and P. robustus jaws are distinct in terms of the ratio of minimum to maximum second moments of area. This difference most likely represents a structural response to elevated torsional moments in the fossil hominids. Although the relative amount of compact bone in cross‐section does not differ significantly between taxa by statistical criteria, A. africanus utilizes less cortical bone than P. robustus in the same manner in which Pongo is separated from the condition in other extant large‐bodied hominoids. It has been suggested that the phenomenon of mandibular “robusticity” (expressed as an index of corpus breadth/corpus height) may be an effect of postcanine megadontia and/or reduced canine size in the australopithecines. Results presented here, however, indicate that it is unlikely that either factor adequately accounts for mandibular size and shape variation in early hominids.
Is the Narmada hominid an Indian Homo erectus?
Authors: Kennedy Kenneth A. R. , Sonakia Arun , Chiment John , Verma K. K.
Published: February 2006

In 1982 a fossil hominid calvaria was found in a middle Pleistocene deposit in the central Narmada valley of Madhya Pradesh, India, and was assigned to the new taxon Homo erectus narmadensis. Subsequently, morphometric studies of the specimen were conducted by two separate research teams from France and the United States, both in collaboration with Indian colleagues. Results of the most recent study, which includes morphometric and comparative investigations, lead to the conclusion that “Narmada Man” is appropriately identified as Homo sapiens. While the calvaria shares some anatomical features with Asian Homo erectus specimens, it exhibits a broader suite of morphological and mensural characteristics suggesting affinities with early Homo sapiens fossils from Asia, Europe, and Africa as well as demonstrating that the Narmada calvaria possesses some unique anatomical features, perhaps because the specimen reflects the incoherent classificatory condition of the genus Homo.
Percent osteonal bone versus osteon counts: The variable of choice for estimating age at death
Authors: Stout Sam D. , Stanley Sarah C.
Published: February 2006

Ahlqvist and Damsten's (1969) modification of the Kerley (1965) method for histological age estimation uses percent osteonal bone, rather than actual osteon counts, in order to eliminate the difficulty of distinguishing between intact and fragmentary osteons. Since their method has been developed for the femur only, and several more recent methods have been proposed that utilize percent osteonal bone, a study was undertaken to ascertain the relative value of percent osteonal bone compared with osteon counts to estimate age at death for the radius, tibia, and fibula.

First the question of how much of the cross‐section of a bone should be sampled was addressed by comparing the results of regression against age for percent osteonal bone derived from sampling only four fields with those derived from the entire cross‐section of the radius. A significant age association was found only when the entire cross‐section was sampled.

In order to evaluate the relative merit of using either percent osteonal bone, or osteon counts to estimate age, each variable was regressed against age predictor.

Finally, a repeated measures analysis of variance revealed that percent osteonal bone and osteon counts both differ among the three bones within an individual.

Based upon these results, osteon counts, rather than percent osteonal bone, should be the variable of choice when developing histological age predicting methods.
Allometry and prediction in Hominoids: A solution to the problem of intervening variables
Authors: Hartwig‐Scherer Sigrid , Martin Robert D.
Published: February 2006

To avoid misinterpretation of allometric exponents determined from interspecific allometric comparisons, specific conditions must be met with respect to the common reference variable. Body weight is considered to be the best general indication of overall size and is hence widely acknowledged to be the most suitable reference variable. However, because of the paucity of recorded body weights for museum specimens, various comparative studies have used other size indicators as intervening variables, although the allometric relationships to body size/weight were often unknown and possibly differed between species. Because of differences in the scaling properties of alternative intervening variables across the species investigated, conflicting conclusions may be drawn if different variables are chosen as substitutes for overall size. This is illustrated with two examples. In this study, series of skeletons with associated body weights of Gorilla, Pan, Pongo, and Homo were investigated. Both ontogenetic and static adult allometric relationships between several widely used reference variables and body weight were determined. Neither these variables nor additional estimators investigated in this study displayed allometric exponents and coefficients similar enough across species to justify direct interspecific comparison. To generate an alternative size estimator for both ontogenetic and static interspecific investigations, equations for combined sexes were derived to predict body weight from various long bone dimensions for individual hominoid species. From a total of 25 predictors, 12 prediction equations per species (six for nonadults and six for adults) were selected according to their relative suitability for reliable prediction of body weight. It is shown that the derived reference variable “predicted body weight” avoids problems of intervening variables, is valid for any interspecific ontogenetic and static allometric comparison, and displays less fluctuation in comparison to actual body weight. © 1992 Wiley‐Liss, Inc.
Three‐dimensional finite element stress analysis of the dentate human mandible
Authors: Korioth Tom W. P. , Romilly Douglas P. , Hannam Alan G.
Published: February 2006

The biomechanical events which accompany functional loading of the human mandible are not fully understood. The techniques normally used to record them are highly invasive. Computer modelling offers a promising alternative approach in this regard, with the additional ability to predict regional stresses and strains in inaccessible locations. In this study, we built two three‐dimensional finite element (FE) models of a human mandible reconstructed from tomographs of a dry dentate jaw. The first model was used for a complete mechanical characterization of physical events. It also provided comparative data for the second model, which had an increased vertical corpus depth. In both cases, boundary conditions included rigid restraints at the first right molar and endosteal cortical surfaces of the articular eminences of temporal bones. Groups of parallel multiple vectors simulated individual masticatory muscle loads. The models were solved for displacements, stresses, strains, and forces. The simulated muscle loads in the first model deformed the mandible helically upward and toward its right (working) side. The highest principal stresses occurred at the bite point, anterior aspects of the coronoid processes, symphyseal region, and right and left sides of the mandibular corpus. In general, the observed principal stresses and strains were highest on the periosteal cortical surface and alveolar bone. At the symphyseal region, maximum principal stresses and strains were highest on the lower lingual mandibular aspect, whereas minimum principal stresses and strains were highest on its upper labial side. Subcondylar principal strains and condylar forces were higher on the left (balancing or nonbiting) side than on the right mandibular side, with condylar forces more concentrated on the anteromedial aspect of the working‐side condyle and on the central and lateral aspects of the left. When compared with in vivo strain data from macaques during comparable biting events, the predictive strain values from the first model were qualitatively similar. In the second model, the reduced tensile stress on the working‐side, and decreased shear stress bilaterally, confirmed that lower stresses occurred on the lower mandibular border with increased jaw depth. Our results suggested that although the mandible behaved in a beam‐like manner, its corpus acted more like a combination of open and closed cross sections due to the presence of tooth sockets, at least for the task modelled. Although restricted by an oversimplified representation of mandibular structure, limited data which described the behaviour of its various material components, and approximation of the behaviour within and between groups of jaw muscles, our FE‐based predictions were consistent with current notions of mandibular mechanics derived from experimental recordings in man and nonhuman primates. © 1992 Wiley‐Liss, Inc.
Diet and dental caries among later stone age inhabitants of the Cape Province, South Africa
Authors: Sealy J. C. , Patrick M. K. , Morris A. G. , Alder D.
Published: February 2006

Stable carbon isotope measurements and incidences of dental caries are presented for three groups of prehistoric human skeletons from different regions of the Cape Province, South Africa. The isotopic analyses of bone collagen demonstrate the importance of marine foods in the diet and vary through time, across space, and according to sex. The incidence of dental caries ranges from 0% among heavily marine‐dependent individuals from the south‐western Cape coast, to 17.7% among skeletons from an archaeological site on the south coast. The extremely high incidence of caries in a hunter‐gatherer population may be related to lack of fluoride in the water. © 1992 Wiley‐Liss, Inc.
Homology and evolution of the orbitotemporal venous sinuses of humans
Authors: Diamond Michael K.
Published: February 2006

The orbitotemporal venous sinuses accompany the intracranial branches of the stapedial artery. These sinuses are large in primitive primates and drain the extensive territories supplied by the stapedial artery as well as the brain. The orbit is drained by a wide cranio‐orbital sinus which empties into the postglenoid emissary vein. Also emptying into the postglenoid vein is the petrosquamous sinus. The latter diverts cerebral blood from the transverse sinus and also drains the temporalis muscle. Emptying into both the cranio‐orbital and petrosquamous sinuses are meningeal tributaries, which drain the cranial side wall and the dura mater. The relatively small sinus communicans runs in the angle between the petrosal bone and the cranial side wall. It commences at the postglenoid vein and connects the distal end of the petrosquamous sinus to the pterygoid venous plexus. In humans, the orbitotemporal sinus system is greatly modified. Its remnants persist for the most part as “middle meningeal veins.” The system no longer drains the orbit, the temporal fossa, or the brain. The petrosquamous sinus becomes attenuated or obliterated along part or all of its length. The postglenoid vein vanishes. The cranio‐orbital sinus is reduced in diameter and its connection to the orbit is feeble or absent. During development, the posterior end of the cranio‐orbital sinus migrates inferiorly along the sinus communicans. In most individuals, this migration ceases at the foramen spinosum, site of the emissary vein of the sinus communicans. Meningeal tributaries are relatively large in humans, and drain principally into the cranio‐orbital sinus or sphenoparietal sinus. The sphenoparietal sinus is an evolutionary novelty restricted to hominoids and is frequently developed in onlyHomoandPongo. © Wiley‐Liss, Inc.
Molecular and classical cytogenetic analyses demonstrate an apomorphic reciprocal chromosomal translocation in Gorilla gorilla
Authors: Stanyon R. , Wienberg J. , Romagno D. , Bigoni F. , Jauch A. , Cremer T.
Published: February 2006

The existence of an apomorphic reciprocal chromosomal translocation in the gorilla lineage has been asserted or denied by various cytogeneticists. We employed a new molecular cytogenetic strategy (chromosomal in situ suppression hybridization) combined with high‐resolution banding, replication sequence analysis, and fluorochrome staining to demonstrate that a reciprocal translocation between ancestral chromosomes homologous to human chromosome 5 and 17 has indeed occurred. © 1992 Wiley‐Liss, Inc.
Nutritional status of adults in rural Mali
Authors: Dettwyler Katherine A.
Published: February 2006

An anthropometric assessment was conducted of 441 adults from six rural villages in southern Mali. As is typical for human populations, females are shorter and lighter than males. Both females (N = 320) and males (N = 121) are shorter and lighter than their U.S. counterparts. Mean weight in the sample is 53.4 ± 8.5 kilos for females and 58.8 ± 6.5 kilos for males. Mean height is 160.4 ± 5.7 cm for females and 171.3 ± 6.6 cm for males. The data for height in males are very similar to those reported from other surveys in Mali, and show no evidence for a positive secular trend in height. Mean body mass index (BMI) is 20.8 for females and 20.0 for males. These are lower than U.S. averages, but well above suggested cutoff points for malnutrition in adults. Average arm circumference is 26.5 cm for females and 26.4 cm for males. Females have relatively large arm circumferences due, in part, to the heavy manual labor they perform. Average head circumference is 53.0 cm for females and 54.8 cm for males. For both sexes, these values are more than 1 standard deviation (SD) below the U.S. means. Adult values for anthropometric measurements reflect childhood stresses of malnutrition and disease, and a lifetime of accommodation to a high‐carbohydrate, low‐protein diet, and hard physical labor. Females are significantly closer to the U.S. standards than males for weight, height, BMI, and arm circumference; these findings support the idea that females are buffered from environmental stresses relative to males. In addition, females exhibit significantly more variability than males for weight, arm circumference, and head circumference, but not for height, suggesting that variability in adult height does not reflect the presence or absence of female buffering or the level of environmental adversity. © 1992 Wiley‐Liss, Inc.
Erosive arthritis and spondyloarthropathy in old world primates
Authors: Rothschild Bruce M. , Woods Robert J.
Published: February 2006

Presence of spine and sacroiliac involvement and the nature and distribution of the erosive lesions allow definitive diagnosis of Spondyloarthropathy. Thus, Spondyloarthropathy was identified in Theropithecus, Papio, Cercopithecus, Macaca, Colobus, Presbytis, and Hylobates. Only monarticular erosive disease was present in prosimians, precluding a diagnosis of Spondyloarthropathy for that group. The distribution of erosive disease and axial joint involvement in 1,349 non‐prosimian Old World primates is quite characteristic of that noted in human psoriatic arthritis. While Reiter's syndrome must also be considered, the histologic appearance of skin lesions in Macaca is characteristic of psoriasis.

Evidence of Spondyloarthropathy abounds in the literature of primate skeletal disease. Environmentally based contagions may be important in the pathophysiology of spondyloarthropathy. The wide geographic distribution of the phenomena in monkeys suggests a “panendemic,” with limited individual susceptibility (compared to that noted in gorillas and chimpanzees). Identical occurrence of erosive arthritis/spondyloarthropathy in free‐ranging and artificially restrained animals suggests that spondyloarthropathy can validly be studied in artificially restrained populations. This perspective should allow application of human therapeutic approaches to and perhaps improve the quality of life for artificially restrained, afflicted individuals. © 1992 Wiley‐Liss, Inc.
Dietary and dental adaptations in the Pitheciinae
Authors: Kinzey Warren G.
Published: February 2006

Since Mivart (1865), Cacajao, Chiropotes, and Pithecia have been grouped into a single taxon, which he called the subfamily Pitheciinae but which I, following Rosenberger (this issue), refer to as the living members of the tribe Pitheciini. While few today doubt the association of these three living genera, not all would place them together with Aotus and Callicebus in the subfamily Pitheciinae. This is an attempt to sort out the behavioral and morphological features of feeding and dental morphology in these taxa. Extant members of the tribe Pitheciini are adapted for sclerocarpic foraging, morphological evidence for which is found in the fossils of Soriacebus and Cebupithecia. Sclerocarpic foraging in living pitheciins is a two‐stage process of seed predation involving 1) specialized features of the anterior dentition that allow removal of a hard pericarp that protects a seed or seeds, followed by 2) mastication by the posterior dentition having low cusp relief to triturate nutritious seeds of a relatively soft and uniformly pliable consistency. The dentitons of fossil pitheciins, Soriacebus and Cebupithecia, demonstrate that the hypertrophy of lower incisors plus the robustness and flaring of the canine precede development of low cusp relief on molars and premolars in the evolution of morphological features associated with sclerocarpic foraging. Features of sclerocarpic foraging are found less uniformly in the other two pitheciines, Callicebus and Aotus. © 1992 Wiley‐Less, Inc.
Atelinae adaptations: Behavioral strategies and ecological constraints
Authors: Strier Karen B.
Published: February 2006

Comparisons between the four genera that make up the Atelinae reveal two distinct behavioral patterns, one in which energy expenditure is minimized (Alouatta) and one in which energy intake is maximized (Lagothrix, Ateles, and Brachyteles). Among the atelins, Lagothrix and Ateles devote over 75% of their annual feeding time to fruit, while Brachyteles devotes between 50% and 67% of their feeding time to leaves. Pronounced seasonality in the Atlantic coastal forest inhabited by Brachyteles may be responsible for its more folivorous diet. Alouatta falls in the body size range of Lagothrix and is much smaller than Ateles and Brachyteles. Nonetheless, Alouatta is more folivorous than sympatric atelins. The atelins also share a rapid, suspensory mode of locomotion that appears to enable them to minimize travel time between widely dispersed fruit sources. Alouatta, by contrast, employs a slower, but more energetically efficient, quadrupedal locomotion. Ranging patterns among the Atelinae are consistent with both diet and locomotor abilities: Atelins travel daily distances up to 5,000 m; Alouatta ranges are much shorter. Further distinctions are evident in Atelinae grouping patterns. Alouatta remains in small cohesive groups that occupy home ranges less than 60 ha in size. Both Lagothrix and Ateles have large groups that fission to reduce the costs of intragroup feeding competition when preferred fruits occur in small patches within much larger community ranges. While greater reliance on low‐energy foods such as leaves may release Brachyteles from similar competitive constraints, their tendency toward fluid grouping associations is consistent with the pursuit of a frugivorous diet. © 1992 Wiley‐Liss, Inc.
Evolution of feeding niches in new world monkeys
Authors: Rosenberger Alfred L.
Published: February 2006

The adaptive radiation of modern New World monkeys unfolded as the major lineages diversified within different dietary‐adaptive zones predicated upon a fundamentally frugivorous habit. The broad outlines of this pattern can be seen in the fossil record, beginning in the early Miocene. Cebids are obligate frugivorous predators. The smallest forms (Cebuella,Callithrix) are specialized exudativores, and the largest (cebines) are seasonally flexible omnivores, feeding particularly on insects (Saimiri) or “hard” foods, such as pith and palm nuts (Cebus), when resources are scarce. The smaller‐bodied atelids (Callicebus,Aotus) may use insects or leaves opportunistically, but pitheciins (saki‐uakaris) specialize on seeds as their major protein source.The larger atelines (Alouatta,Brachyteles) depend on leaves or on ripe fruit (Ateles). Locomotion, body size, and dietary adaptations are linked: claws and small body size opened the canopy‐subcanopy niche to callitrichines; climbing and hanging, the fine‐branch setting to the atelines; large size and strength, semiprehensile tails, and grasping thumbs, the extractive insectivory ofCebus; deliberate quadrupedalism, the energy‐saving transport of folivorousAlouatta. Body size increases and decreases occurred often and in parallel within guilds and lineages. Conventional dietary categories, particularly frugivory, are inadequate for organizing the behavioral and anatomical evidence pertinent to evolutionary adaptation. Related models of morphological evolution based on feeding frequencies tend to obfuscate the selective importance of “critical functions,” responses to the biomechanically challenging components of diet that may be determined by a numerically small, or seasonal, dietary fraction. For fossils, body size is an unreliable indicator of diet in the absence of detailed morphological information. More attention needs to be given to developing techniques for identifying and quantifying mechanically significant aspects of dental form, the physical properties of primate foods, their mode of access, and the cycles of availability and nutritional value. © 1992 Wiley‐Liss, Inc.
Smoking and pulmonary function in five Solomon Island populations
Authors: Byerley David M. , Weitz Charles A , Richards Frank
Published: February 2006

The relationship between smoking and lung function was examined in a large sample of healthy Solomon Island Melanesians and Polynesians as part of a multidisciplinary study carried out in 1985 and 1986. Comparisons are made between samples of smokers and non‐smokers to determine if smoking is associated with a reduction in pulmonary function among males and females between 25 and 75 years of age.

The results of this study indicate that cigarette smoking causes singnificant reductions in the pulmonary function of these populations. In addition, a clear difference in pulmonary function between males and females, as well as a general reduction in female FEV1 values, suggests that cooking smoke inhalation may be operating as a possible risk factor to the pulmonary health of women. Further research is needed to quantify exposure to smoke of both males and females and relate this measure to declines in pulmonary function. © 1992 Wiley‐Liss, Inc.
Plantigrady and foot adaptation in African apes: Implications for hominid origins
Authors: Gebo Daniel L.
Published: February 2006

In living primates, except the great apes and humans, the foot is placed in a heel‐elevated or semi‐plantigrade position when these animals move upon arboreal or terrestrial substrates. Heel placement and bone positions in the non‐great ape primate foot are designed to increase mobility and flexibility in the arboreal environment. Orangutans have further enhanced foot mobility by adapting their feet for suspension and thus similarly utilize foot positions where the heel does not touch the substrate. Chimpanzees and gorillas represent an alternative pattern (plantigrady), in which the heel contacts the surface of the support at the end of swing phase, especially during terrestrial locomotion. Thus, chimpanzees and gorillas possess feet adapted for both arboreal and terrestrial substrates. African apes also share several osteological features related to plantigrady and terrestrial locomotion with early hominids. From this analysis, it is apparent that hominid locomotor evolution passed through a quadrupedal terrestrial phase. © 1992 Wiley‐Liss, Inc.
Genital swelling in females of the monogamous gibbon, Hylobates (H.) lar
Authors: Dahl Jeremy F. , Nadler Ronald D.
Published: February 2006

Cyclical changes in the vulvae of five adult lar gibbons (Hylobates [H.] lar) were studied and compared with those of eight lowlandgorillas. The results reveal that the gibbons have relatively conspicuous and specialized sexual swellings that alter shape and appearance during the ovarian cycle. At maximum extent, the genital swellings of gorillas are relatively and absolutely smaller than those of gibbons, and lack the distinctive coloration seen in the genital swellings of the smaller apes. We conclude that the female gibbon's sexual swelling is a far more conspicuous and effective signal of estrus status than that of the gorilla, and that this is not explicable in terms of allometry. Previous investigators have pointed to one‐male mating systems, monogamous pair‐bonding, or an arboreal habitat as reasons that some primates should have less conspicuous signals of estrus than others. Our findings for the gibbon are the reverse of these predictions, and indicate that sexual selection other than by intermale competition for estrous females is implicated in the ultimate causation of the gibbon's swelling. The adaptive value and significance of the female gibbon's sexual signals remain unclear, However. © 1992 Wiley‐Liss, Inc.
Age‐ and gender‐related changes in body size, adiposity, and endocrine and metabolic parameters in free‐ranging rhesus macaques
Authors: Schwartz Susan M. , Kemnitz Joseph W.
Published: February 2006

Normative age‐ and gender‐related changes in body composition, serum lipids, testosterone, and insulin‐like growth factor (IGF‐1) were examined in the Cayo Santiago free‐ranging rhesus macaques. In both adult males and females, body weights, crown‐rump lengths, and circumference of the limbs were lowest in the oldest group (20+ years of age) as compared with other adult age classes. Body fat, as reflected in subcutaneous fatfold thickness and waist/thigh ratios, were higher in adult females than adult males. This gender dimorphism was first detectable among the 6–9 year old age group. Greatest body fat among females was observed in the 10–14 age group, whereas in males the highest values were observed in the 15–19 age group. Differences in body composition were also observed with respect to reproductive status. Although there were no gender differences in overall cholesterol levels, there were age‐related differences between males and females, and only in males were cholesterol values positively related to adiposity. There were no age‐ or gender‐related differences in triglyceride values, but levels were significantly higher in pregnant females in comparison with other reproductive states. Levels of testosterone were not significantly related to any morphometric parameter and values did not decrease significantly with age. Levels of IGF‐1 exhibited a significant age‐related decrease among adult males, and females had higher levels independent of age. The similarities between the present findings and human studies suggest that further studies in the free‐ranging rhesus macaques would provide a bridge between studies of laboratory‐housed primates and studies of human beings with respect to the etiology of obesity and life‐history changes in body composition and endocrine and metabolic parameters. © 1992 Wiley‐Liss, Inc.
Computed tomography and enamel thickness of maxillary molars of Plio‐Pleistocene hominids from Sterkfontein, Swartkrans, and Kromdraai (South Africa): An exploratory study
Authors: Macho Gabriele A. , Thackeray J. Francis
Published: February 2006

This paper is one in a series which explores the possibility of using the non‐destructive CT technique to identify patterns in tooth enamel distribution and structure of hominid molars from Plio‐Pleistocene sites in South Africa, notably Swartkrans, Sterkfontein, and Kromdraai. Whereas previous investigators have emphasised gross differences in absolute and relative or average enamel thickness between hominid taxa, the present study highlights differences in enamel thickness over functionally significant regions of the crown. Differences in the distribution of enamel in A. robustus, A. africanus, and Homo sp. are identified through the use of bivariate and multivariate analyses, and are interpreted in terms of dietary regimes. © 1992 Wiley‐Liss, Inc.
Congenital syphilis in the past: Slaves at Newton Plantation, Barbados, West Indies
Authors: Jacobi Keith P. , Cook Della Collins , Corruccini Robert S. , Handler Jerome S.
Published: February 2006

Hutchinson's incisors and Moon's molars are specific lesions of congenital syphilis. The extensive but fragmentary clinical literature on these conditions describes reduced dimensions and thin enamel in the permanent incisors and first molars, crowding and infolding of the first molar cusps, notching of the upper incisors, and apical hypoplasias of the permanent canines. A Barbados slave cemetery (ca. 1660–1820 AD) includes three individuals with these features, suggesting a frequency at birth of congenital syphilis in the population approaching 10%. These three cases show triple the frequency of all hypoplasias and more than seven times the frequency of pitting hypoplasia present in the remainder of the series. The recognizable congenital syphilis cases account for much of the remarkably high frequency of hypoplasias in the series as a whole. We infer that syphilis contributed substantially to morbidity, infant mortality, and infertility in this population. Presence or absence of congenital syphilis may account for much of the variability in health and mortality seen among nineteenth century African‐American populations. © 1992 Wiley‐Liss, Inc.
Relationship of squamosal suture to asterion in pongids (Pan): Relevance to early hominid brain evolution
Authors: Holloway Ralph L. , Shapiro Jill S.
Published: February 2006

Based on 244 measurements of the relationship of the squamosal suture to the landmark asterion in 49 chimpanzee skulls, it is shown that in the normal lateral view the squamosal suture is very rarely inferior to asterion. In hominid crania, the squamosal suture is always well superior to asterion. Even in Pan, that part of the squamosal suture most homologous with the remnant found on the Hadar AL 162–28 Australopithecus afarensis hominid cranial fragment is very rarely inferior to asterion. Such variability suggests that Falk's (Nature 313:45–47, 1985) orientation of the Hadar specimen is incorrect; she places asterion superior to the position of the squamosal suture if projected endocranially. The implication for the brain endocast is that, however the fragment is oriented, the posterior aspect of the intraparietal (IP) sulcus is in a very posterior position relative to any chimpanzee brain. The distance from the posterior aspect of IP to occipital pole is twice as great in chimpanzee brain casts than on the Hadar AL 162–28 endocast, even though the chimpanzee brain casts are smaller in overall size. This suggests that brain reorganization, at least as exemplified as a reduction in primary visual striate cortex (area 17 of Brodmann), occurred early in hominid evolution, prior to any major brain expansion. © 1992 Wiley‐Liss, Inc.
Evolution of the power (“squeeze”) grip and its morphological correlates in hominids
Authors: Marzke M. W. , Wullstein K. L. , Viegas S. F.
Published: February 2006

The “squeeze” form of power grip is investigated for the purposes of clarifying the hand posture and activities associated with the grip, assessing the potential in chimpanzees for using the grip, and identifying morphological correlates of an effective power grip that may be recognized in fossil hominid species. Our approaches include: (1) the analysis of the human grip, focusing on both the hand posture involved and hand movements associated with use of the grip in hammering; (2) the analysis of similar chimpanzee grips and associated movements; (3) comparative functional analysis of regions in the hand exploited and stressed by the grip and its associated movements in humans; and (4) a review of the literature on the power grip and its morphological correlates. Results of the study indicate that humans use a squeeze form of power grip effectively to wield cylindrical tools forcefully as extensions of the forearm. Several morphological features occur in high frequency among humans which facilitate the grip and are consistent with the large internal and external forces associated with it in hammering and in other tool‐using activities. Chimpanzee hand postures resembling this form of human power grip are not fully comparable and lack some of these morphological correlates that facilitate its use. The hand of Australopithecus afarensis does not appear to have been stressed by use of the grip, but there is some evidence for this type of stress in the metacarpals from Sterkfontein Member 4. Hands from Olduvai and Swartkrans do not provide sufficient evidence for assessment of power grip capabilities. © 1992 Wiley‐Liss, Inc.
Estimating femur and tibia length from fragmentary bones: An evaluation of Steele's (1970) method using a prehistoric European sample
Authors: Jacobs Kenneth
Published: February 2006

Steele's (1970) regression method for estimating femur and tibia length from fragmentary bones is tested on a sample of complete femora (female N = 26; male N = 33) and tibiae (female N = 16; male N = 22) from a number of European Mesolithic and Neolithic sites. Over half of the regression equations given by Steele for predicting maximum length of the bone from the length(s) of one or more of its constituent segments are shown to produce inaccurate predictions in this test sample. However, a closer evaluation of these results, including calculation of regression equations for the test sample itself, reveals that this inaccuracy does not derive from any inherent flaw in Steele's method. Rather, it is shown that differential distribution of maximum bone length among the various bone segments as defined by Steele may occur due to variation in muscular activity pattern and intensity. This argues for the retention of Steele's basic method, with care being taken to match closely the activity pattern typical of the sample from which regression equations are derived with that of the population to which the equations are to be applied. The equations calculated in this study thus are provided for use where deemed appropriate. © 1992 Wiley‐Liss, Inc.
Measurement of subcutaneous adipose tissue using ultrasound images
Authors: Ramirez Maria E.
Published: February 2006

The objectives of this paper are to explore the potential of the ultrasound technique to quantify subcutaneous adipose tissue, and to explain the differences between skinfolds and ultrasound measurements across a large range of ages and levels of adiposity. The sample consisted of 115 men and 117 women aged 35 to 51 years, 132 girls and 145 boys aged 12 to 20 years.

Subcutaneous fat thickness was measured at four sites using skinfolds calipers, and at seven sites using a real‐time B‐mode ultrasound scanner. Anthropometric measurements were obtained, and percent body fat was estimated using electric impedance.

The agreement between skinfolds and ultrasound measurements was calculated for each age and sex group. The agreement between techniques, and the levels of correlation between body composition and fatness measurements were high in the sample of young men. However, the results were less consistent in the other groups. Site specific differences were also noted. © 1992 Wiley‐Liss, Inc.
Probit and survival analysis of tooth emergence ages in a mixed‐longitudinal sample of chimpanzees (Pan troglodytes)
Authors: Kuykendall Kevin L. , Mahoney C. James , Conroy Glenn C.
Published: February 2006

Tooth emergence data from a mixed‐longitudinal sample of 58 chimpanzees of known age were analyzed using probit and survival techniques to produce median emergence ages, ranges of variability, and emergence sequences for primary and permanent teeth. Between‐group comparisons were made to test for statistically significant differences in emergence ages. No such differences were found between right and left sides, or between maxilla and mandible, for any primary or permanent teeth. Male‐female comparisons did demonstrate significant emergence‐age differences for some teeth, although they were not always bilaterally symmetrical. More complete data are required to further clarify the nature of sex differences in tooth emergence in chimpanzees. Regression models for age prediction from the number of emerged teeth were generated and indicate that males achieve a given number of emerged teeth at a significantly later age than females. However, when fewer than five teeth have emerged, males are predicted to be younger than females. The sizable root mean square error values for these models suggest that this method of age prediction has limited usefulness owing to the amount of variability in timing of tooth emergence in chimpanzees. The implications of these data for studies on tooth emergence in early hominids are addressed. © 1992 Wiley‐Liss, Inc.
Gene geography of South America: Testing models of population displacement based on archeological evidence
Authors: Rothhammer Francisco , Silva Claudio
Published: February 2006

Gene frequencies for 13 marker systems are used to construct synthetic gene frequency maps of South America. The surfaces generated using the first three principal components exhibit clines which validate models of population displacement based on archeological data and a previous analysis of craniometrical variation. © 1992 Wiley‐Liss, Inc.
Human marriage systems and sexual dimorphism in stature
Authors: Gaulin Steven J. C. , Boster James S.
Published: February 2006

Contemporary populations of Homo sapiens are sexually dimorphic on a variety of traits. In terms of stature, men are reliably between 4% and 10% taller than women in well‐sampled human populations. Are cross‐cultural differences in the magnitude of sexual dimorphism consistent with expectations from sexual selection theory? Prior studies have provided conflicting answers to this question in part because they failed to agree on how the force of sexual selection should or could be operationalized. Here we offer a simple and unbiased method for operationalizing sexual selection and retest two separate predictions from earlier work (Alexander et al., 1979) about its expected impact on stature dimorphism in a sample of 155 societies. Neither prediction matches the observed cross‐cultural distribution of dimorphism. However, this is not the consequence of a random distribution of dimorphism across societies. Instead, the data exhibit a robust and unexpected pattern. © 1992 Wiley‐Liss, Inc.
Biomechanical analysis of masticatory system configuration in Neandertals and Inuits
Authors: Spencer M. A. , Demes B.
Published: February 2006

Considerable debate has surrounded the adaptive significance of Neandertal craniofacial morphology. Numerous unique morphological features of this form have been interpreted as indicating an adaptation to intense anterior tooth use. Conversely, it has been argued that certain features related to muscle position imply a reduced mechanical advantage for producing bite forces on the incisors and canines. In this study, hypotheses about morphological specializations for anterior tooth use have been derived from a biomechanical model of Greaves (1978). These hypotheses were tested by performing separate pairwise comparisons of Neandertals and early Homo sapiens, and Inuits and Native Americans from Utah. Inuits are known to have produced repeated and high magnitude forces on their anterior dentition and therefore serve as a good model for a hominid adapted to intensive anterior tooth use. Biomechanically relevant dimensions of the masticatory system were measured using a computer‐driven video analysis system and compared between the two taxa in each comparison. The results of this study reveal a number of similarities between the morphological specializations exhibited by Neandertals and Inuits that can be related to intensified anterior tooth use. The hypothesis that Neandertals were poorly designed for producing masticatory forces is rejected. Specializations that differ between the two groups are interpreted as being the result of differential functional demands placed on the postcanine dentition in Neandertals and Inuits. It is suggested that many of the unique morphological features of the Neandertal face are a response to intensified use of the anterior dentition and the need to retain a sufficiently large postcanine occlusal area necessary for a relatively high attrition diet. © 1993 Wiley‐Liss, Inc.
Genetic relationships of European populations reflect their ethnohistorical affinities
Authors: Sokal Robert R. , Jacquez Geoffrey M. , Oden Neal L. , DiGiovanni Donna , Falsetti Anthony B. , McGee Elizabeth , Thomson Barbara A.
Published: February 2006

From 420 records of ethnic locations and movements since 2000 B. C., we computed vectors describing the proportions which peoples of the various European language families contributed to the gene pools within 85 land‐based 5 × 5‐degree quadrats in Europe. Using these language family vectors, we computed ethnohistorical affinities as arc distances between all pairs of the 85 quadrats. These affinities are significantly correlated with genetic distances based on 26 genetic systems, even when geographic distances, a common causative factor, are held constant. Thus, the ethnohistorical distances explain a significant amount of the genetic variation observed in modern populations. Randomizations of the records by chronology result in loss of significance for the observed partial correlation between genetics and ethnohistory, when geography is held constant. However, a randomization of records by location only results in reduced significance. Thus, while the historical sequence of the movements does not seem to matter in Europe, their geographic locations do. We discuss the implications of these findings. © 1993 Wiley‐Liss, Inc.
Mandible of Ouranopithecus macedoniensis (Hominidae, primates) from a new late Miocene locality of Macedonia (Greece)
Authors: Koufos George D.
Published: February 2006

In 1990, a new late Miocene locality named “Nikiti 1” or NKT, was discovered near the village of Nikiti (Chalkidiki, Macedonia, Greece) about 100 km east of Thessaloniki City. The locality is situated in the Nikiti Formation, which consists of yellowish sands, gravels and pebbles and has been dated to late Vallesian–early Turolian. Among the initially collected fossils there is a mandible of a hominoid primate, which is described, compared, and attributed to Ouranopithecus macedoniensis. A short review of the species in Macedonia and its phylogenetic relationships are also given. © 1993 Wiley‐Liss, Inc.
Variables affecting dental fluctuating asymmetry in human isolates
Authors: Hershkovitz I. , Livshits G. , Moskona D. , Arensburg B. , Kobyliansky E.
Published: February 2006

The aims of the present study are to 1) determine and describe levels of dental fluctuating asymmetry (FA) in a highly endogamous human group; 2) evaluate the effects of various FA measures on perceived FA levels and their interrelationships; 3) study the connections between dental variables (tooth size, class, position, type, location and dimension) and FA levels; and 4) estimate the interrelationships between dental FA measures. The study was carried out on 242 Bedouin boys aged 5 to 14 years. The results demonstrate that the main variables influencing dental FA levels within this population are tooth class (incisors, canine, premolars, molars) and position (mesial, distal) and that the interaction between the two is significant. When sample sizes are large enough and individual measures are needed for the statistical analysis, the use of a computational method based on absolute values is legitimate. Clear relationships between some FA dental traits are discerned though principal‐components analysis. © 1993 Wiley‐Liss, Inc.
Cannibalism in Chaco Canyon: The charnel pit excavated in 1926 at Small House ruin by Frank H.H. Roberts, Jr.
Authors: Turner Christy G.
Published: February 2006

A charnel pit that contained the disarticulated and intentionally damaged remains of eight incomplete adult and subadult Anasazi skeletons was found and excavated in 1926 by F. H. H. Roberts, Jr., at an AD 900 ruin he named Small House, located in Chaco Canyon, northwestern New Mexico. Damage includes extensive perimortem cranial and postcranial bone breakage, cut marks, anvil hammerstone abrasions, burning, many missing vertebrae, and fragment end‐polishing. Together, these six types of perimortem damage are believed to be the taphonomic signature of prehistoric Anasazi cannibalism. The possible cause of the Small House episode is discussed within the framework of two explanatory models‐random social pathology and institutionalized social control by violent means. © 1993 Wiley‐Liss, Inc.