bluuebunny/crossref_metadata_2025 huggingface dataset:
Dermatoglyphics and anthropometric relationships within the Iñupiat (Eskimo) hand
Authors: Jamison Cheryl Sorenson , Jamison Paul L. , Meier Robert J.
Published: February 2006

On the basis of earlier findings with Easter Islanders suggesting a positive correlation between dermatoglyphic variables and hand anthropometric measurements, the present study was designed to determine if such a relationship could be generalized to another population, namely, Iñupiat (Eskimo). Since some dermatoglyphic and anthropometric variables were available for both sides of the body, the extension of this study to explore the question of asymmetry was also possible. The Iñupiat sample numbered 142 male and 176 female adult inhabitants of five Alaskan North Slope communities. The major findings of this study included, for males, significant negative correlations between left arm length and digital ridge counts and positive relationships between the palmar variable of axial index and hand length on both hands. For females, the hand breadth/length index was negatively related to most of the digital variables. Very little definitive information regarding the relationship of the asymmetry variables between the two types of measures was ascertained.
Size of the sella turcica and its relation to iron deficiency anemia: A prehistoric example
Authors: Fairgrieve Scott I.
Published: February 2006

This paper examines the usefulness of volume and area assessments of the sella turcica from radiographs in order to aid in the differential diagnosis of iron deficiency anemia in past populations. Lateral and posterior‐anterior radiographs were taken of each cranium in the sample. The length, depth, and width of the sella turcica were then measured directly from the appropriate view, and subsequently the volume and area were calculated for each. The 20–25 year‐old cohort was found to yield the most promising results; however, a statistical difference was not found to exist using the volume or area. The width dimension was found to be of far more use than any other in this study. In no instance was any feature of typical porotic hyperostosis, visually or radiographically, found to be statistically correlated with any difference in the dimensions of the sella turcica. A discussion of how the various dimensions of the sella turcica react to changes in size of the hypophysis cerebri is presented.
Continuous‐variable quantification of dermatoglyphic whorl patterns: A statistical study of angular measurements
Authors: Singh Chanchal , McKnight Karl B.
Published: February 2006

Core(s) and triradii of dermatoglyphic whorl patterns were joined together to form triangles. Base angles of these triangles were measured (in degrees). The tangent angle at the lower edge of a ridge crossing the core—triradius line was also measured in degrees on each side of the whorl. Significant differences and similarities of these angles were investigated for unrelated Caucasian males and females by the use of Student's t‐ and Pearson's r‐tests. Angular findings were related to the corresponding information provided by ridge counts. Similarities and differences between males and females are described.
The choice of a statistic for testing hypotheses regarding seasonality
Authors: Reijneveld Sijmen A.
Published: February 2006

This paper discusses statistical methods for testing hypotheses of seasonality in births across one year, using monthly frequencies. It argues that the Freedman test, a variant of the Kolmogorov‐Smirnov one‐sample test, and the Edwards test and its modifications are most appropriate for this purpose. These tests take into account the order of the monthly frequencies and have a higher power than the oridinary chi‐square goodness‐of‐fit test, regarding seasonality. The paper addresses some points mentioned in earlier papers by McCullough, and O'Brien and Holbert.
Social organization of the pygmy chimpanzee (Pan paniscus): Multivariate analysis of intracommunity associations
Authors: White Frances J. , Burgman Mark A.
Published: February 2006

We examined association patterns of wild, nonprovisioned pygmy chimpanzees in the central rain forest of Zaire. Associations among individuals within two communities (Hedons and Rangers) and one splinter group (Blobs) were described using two measures: the proportion of time spent together in parties, and the proportion of time spent in close proximity while feeding. Patterns were exposed using multivariate analysis and tested using nonparametric (Mantel) tests. Associations among females characterized the social interactions of both Hedons and Blobs. Associations among males, and between males and females, were common only for the Rangers. Parties of Blobs tended to be small (average size: 4), whereas parties of Hedons were of variable size (average: 7), and those of Rangers were predominantly large (average: 10). Thus, variation in association patterns corresponded loosely to differences in party size. Associations among females were most prevalent in small parties. By contrast, associations among males and between males and females were more apparent in large parties. This intracommunity correlation of social organization and party size parallels differences between the Lomako and Wamba study sites. This relationship may reflect the importance of female alliances when food is limited and the ability of single males to monopolize small, but not large, parties of associated females.
Effects of speed on forelimb joint angular displacement patterns in vervet monkeys (Cercopithecus aethiops)
Authors: Vilensky Joel A. , Gankiewicz Eva
Published: February 2006

Shoulder, elbow and wrist joint angular displacement patterns were analyzed for five vervet monkeys across increasing speed. Within symmetrical gaits, the peak positions of the pattern for each joint tended to decrease with increasing speed as did the yield angle of the elbow (more “yielding”). Across the walk(run)‐gallop transition there were no notable changes in the displacement patterns, but there was a consistent decrease in the range of elbow movements and an increase in the yield angle. Across asymmetrical gaits, there was also a tendency for some of the peak positions to decrease. These results are compared with those available for cats and dogs, and are interpreted relative to functional and neurological aspects of forelimb movements in primates.
Occlusal force and craniofacial biomechanics during growth in rhesus monkeys
Authors: Dechow Paul C. , Carlson David S.
Published: February 2006

The masticatory muscles in 132 anesthetized male and female rhesus monkeys ranging in age from juvenile to adult were unilaterally stimulated. Muscle forces and speeds were measured with a bite force transducer positioned at the incisors, premolars, and molars during twitch and tetanic contractions. Lateral cephalographs of all animals were used to estimate the orientation and mechanical advantage of the masticatory muscles. Results showed that maximal occlusal forces increased at a greater rate than body weight during growth. However, maximal occlusal forces increased isometrically relative to mandibular length. Mean forces at the incisors ranged from 70.3 newtons (n) in juveniles up to 139.9 n in adult males. Forces at the molars were 2–2.5 times greater than at the incisors. Time‐to‐peak tension decreased with increasing body size from 44.1 msec in juveniles to 37.4 msec in adult females to 31.0 msec in adult males. Regression analysis showed that adult males have faster muscles than adult females or juveniles even when corrected for body size. Temporalis and masseter orientation was found to change little throughout growth. The mechanical advantage of the masseter and temporalis muscles for producing occlusal forces on the distal molars improved between juveniles and adults, which is contrary to findings of Oyen et al. (Growth 43:174–187, 1979). Among adults, females had a greater mechanical advantage of the masseter muscles than males.
Stature estimation in prehistoric Native Americans of Ohio
Authors: Sciulli Paul W. , Schneider Kim N. , Mahaney Michael C.
Published: February 2006

In the present report we investigate stature estimation techniques in a sample of 64 (35 male, 29 female) prehistoric Native Americans from Ohio. Because living stature is unknown for these 64 individuals, we use Fully's (1956) anatomical method to provide the best estimates of living stature. In this method all osseous components of skeletal height are measured and soft tissue correction is added.

Comparisons of regression equations commonly used for stature estimation in prehistoric Eastern Woodland Native American populations, but developed for East Asian and East Asian—derived populations (using lower extremity components), show that these commonly used equations consistently yield stature estimates 2 to 8 cm in excess of the best estimates from Fully's method.

Based on the skeletal height measures of the 64 individuals in the present sample, we develop regression equations for the estimation of stature. These equations yield stature estimates virtually identical to estimates from Fully's method and may prove useful for stature reconstruction in other prehistoric Eastern Woodland Native American populations.
Opportunity for natural selection among the Indian populations
Authors: Reddy B. Mohan , Chopra Virendra P.
Published: February 2006

A critical review of data on opportunity for natural selection among the Indian populations has been made. These data on 96 populations were analysed according to regional, habitat, and socioeconomic backgrounds. The trends observed on the basis of these Indian data have been compared with worldwide data and data from industrialized nations. As in the industrialized nations, a gradual decrease in Im and It is observed with improving socioeconomic and technological status in the Indian populations. The Indian situation is similar to that of the first phase in the modern demographic transition among the industrialized nations.
Age estimation from cortical index of the human clavicle in northwest Indians
Authors: Kaur Harbir , Jit Indar
Published: February 2006

The proportion of the cortical thickness to the total diameter of the bone (cortical index) was calculated in paired clavicles obtained from 128 male and 82 female medicolegal postmortem subjects who were apparently healthy prior to their accidental death. The ages of the subjects varied from 15 to 85 years. The clavicles were cut either horizontally or parasagittally, and measurements were taken at midclavicle. From the ages of 15 to 30 years, the cortical index increased. It decreased steadily thereafter, with an initial sharp decrease in the age group 31–40 years in both sexes. After the age of 40 years, this rapid decrease in the index continued in the females, but became slow and gradual in the males. Differences between left and right sides were statistically insignificant in both sexes (P > 0.05). However, the sexual differences were significant (P < 0.01) in the age groups from 41 years onwards.
Reliability of age at death in the hamann‐todd collection: Validity of subselection procedures used in blind tests of the summary age technique
Authors: Meindl Richard S. , Russell Katherine F. , Lovejoy C. Owen
Published: February 2006

The blind test procedures used by Lovejoy et al., (Am. J. Phys. Anthropol. 68:1–14, 1985a) have been criticized because they used the Hamann‐Todd collection as their known‐age population. It has been suggested that variation within this sample was reduced by selection procedures designed to ensure accuracy of age at death. Powerful statistical tests for differences in dispersion of ages for pubic symphyseal stages were applied to comparisons between their core sample (N = 238) and those of a large autopsy‐room collection used to develop the Suchey‐Brooks System (N = 530). The variances in ages of the selected Hamann‐Todd Sample are not reduced. The careful subselection of specimens has resulted in a valid statistical core sample for use in the development of aging methodologies.
Histologic examination of age of the first African Baptist Church adults
Authors: Ericksen M. F. , Stix A. I.
Published: February 2006

This study applies a recently formulated method of histologic estimation of age at death to samples of anterior femoral cortex taken from adult skeletons from the First African Baptist Church cemetery and compares the results with macroscopic age estimates made by J. L. Angel and J. O. Kelley. Of the 65 samples taken, 44 were sufficiently well preserved to produce readable thin sections, although most were so fragile that they had to be embedded before sectioning. In most cases the histologic ages agreed with the macroscopic age estimations within the standard error of the estimate of the histologic method. Most cases of disagreement could be attributed to poor preservation. Despite differences between individual gross and microscopic age estimates, the two methods proved to be significantly correlated and produced the same overall demographic picture of a population whose female members were likely to die at earlier ages than the males.
Tooth dislocation: The relationship with tooth wear and dental abscesses
Authors: Clarke Nigel G. , Hirsch Robert S.
Published: February 2006

Tooth dislocation (tilting) was recorded in 1,200 skulls from 34 museum collections. The findings of dislocation by tooth type, tooth wear, and abscess location are presented. A model for dislocation based upon the progressive loss of tooth support provides a rational explanation for the phenomenon. Physiological continuous tooth eruption was considered to account for a component of the progressive loss of tooth attachment. The process of attrition, pulp perforation, and dental abscess cavity formation resulted in further, more severe loss of tooth support. Heavy functional forces, in association with greatly reduced bone support, tilted the crown lingually and root buccally. When the tooth had tilted to such an extent that the root apices protruded from the bone and, presumably (in life) through the gingival/mucosal tissues, the infected root canals were effectively isolated from the internal environment. The tooth continued to function. The more typical consequence of severe attrition and dental abscess formation was tooth loss; it also isolated an infected tooth from living tissue, but without the benefit of retaining function.
Pressure erosion of the femoral trochlea, patella baja, and altered patellar surfaces
Authors: Mann Robert W. , Roberts Charlotte A. , Thomas Michael D. , Davy Dwight T.
Published: February 2006

As knee flexion increases, so do tendofemoral and patellofemoral compression forces. Three cases of long‐standing uncorrected flexion contractures of the knees are presented that resulted in marked erosion of the femoral trochlea, patella baja, and remodeled patellar articular surfaces likely reflecting increased angles of flexion. It is probable that the deep femoral grooves are the result of adaptation under high‐level persistent contact loads from the quadriceps tendon. These examples expand our knowledge of bone remodeling and offer information of potential use in studying ancient skeletal samples.
Premaxillary‐maxillary suture fusion and anterior nasal tubercle morphology in the chimpanzee
Authors: Mooney Mark P. , Siegel Michael I.
Published: February 2006

The anterior nasal spine (ANS) is considered by some to be a unique characteristic of modern humans; however, it has been reported to occur in chimpanzees. Among human populations, ANS size correlates with facial prognathism and timing of premaxillary‐maxillary sutural fusion, which may have implications for models of midfacial growth. To investigate these questions, skulls from 55 chimpanzees (Pan troglodytes) (29 male, 26 female), ranging in age from infants to adults, were examined. None of the 55 specimens examined had a true ANS, but a number of specimens exhibited raised anterior nasal prominences or tubercles (ANT) on the nasal surface of the premaxilla. Female specimens had significantly (P < .05) more ANTs and more extensive fusion of both the palatal and facial components of the suture than did the male specimens. Results from the present study document the presence of an ANT in a sample of chimpanzee crania and are consonant with associations predicted by a septal‐traction model of midfacial growth.
Masticatory‐stress hypotheses and the supraorbital region of primates
Authors: Hylander William L. , Johnson Kirk R. , Picq Pascal G.
Published: February 2006

The purpose of this study is to test various masticatory‐stress hypotheses about the evolution and function of well‐developed browridges of higher primates. This was done by measuring and analyzing patterns of in vivo bone strain recorded from three‐element rosette strain gages bonded to the supraorbital region and to other portions of the bony face of Macaca fascicularis and Papio anubis during mastication and incision. The magnitude and direction of the principal strains recorded support Endo's hypothesis that the supraorbital region during mastication and incision is bent in the frontal plane (Endo, 1966). Our data do not, however, support his hypothesis that the supraorbital region is bent more during incision than during mastication. The data also demonstrate that overall levels of supraorbital strain are not larger in more prognathic subjects. Most importantly, the data indicate that the supraorbital region of nonhuman catarrhines is strained very little during mastication and incision. This indicates that there is much more supraorbital bone than is necessary both to counter masticatory loads and to provide an adequate safety factor to failure for these loads. This in turn suggests that the macaque and baboon browridges can be considerably reduced in size and still maintain these required structural characteristics.

Thus, our experiments provide no support whatsoever for those hypotheses that directly link browridge morphology to masticatory stress (cf. Endo, 1966; Russell, 1983, 1985). A recent review of Endo's original work indicates that this latter statement is also true for humans (Picq and Hylander, 1989). We conclude, therefore, that there is no good reason to believe that enlarged browridges in living and/or fossil primates are structural adaptations to counter intense masticatory forces.

The evolution of browridge morphology in primates is best explained on the basis of factors related to the position of the brain relative to the orbits (Moss and Young, 1960). When these structures are widely separated, as in gorillas, the large intervening space must be bridged with bone. In addition, enough bone must be present within the supraorbital and bridged regions to prevent structural failure due to non‐masticatory external forces associated with highly active primates (e.g., accidental traumatic forces applied to the orbits and neurocranium). This requirement results in both pronounced browridges and in much more supraorbital bone than is necessary to counter routine cyclical stress during mastication and incision. This in turn explains why bone strains recorded from the supraorbital region are extremely small relative to other portions of the primate face during mastication and incision.
Effects of age and gender on the location and orientation of the foramen magnum in rhesus macaques (Macaca mulatta)
Authors: Masters Anne V. , Falk Dean , Gage Timothy B.
Published: February 2006

Endocasts from 378 rhesus macaque skulls from the Cayo Santiago skeletal collection were measured to determine the effects of age and gender on the position and orientation of the foramen magnum. The foramen magnum migrates from a rostral to a caudal position and its angle changes during postnatal development. The angles and relative positions of the foramen magnum are similar for both genders of infants and for both genders of adults. However, analyses of linear response and plateau (LRP) functions reveal significant differences between males and females in the timing of reorientation of the angle and migration of the foramen magnum. The mean adult angle and relative position of the foramen magnum are reached by 4.7 years in females, but they do not achieve their adult values until 7.1 years in males. A similar pattern is observed for the brainstem region of the basicranium. Mean adult lengths of the brainstem region are reached at 5.2 years in females and 7.1 years in males. The relationships between cranial capacity, the growth pattern of the brainstem, and the pattern of change for the angle and the relative position of the foramen magnum are examined. Quantification of the effects of age and gender on the location of the foramen magnum in a large sample of endocasts from one species of higher primate has potential implications for research on human development, and for interpretation of juvenile specimens in the hominid fossil record.
Dental development in South African australopithecines. Part II: Dental stage assessment
Authors: Conroy Glenn C. , Vannier Michael W.
Published: February 2006

Dental development stages of six immature Australopithecus robustus individuals from Swarktrans (SK 61, SK 62, SK 63, SK 64, SK 438, SK 3978) and seven immature Australopithecus africanus individuals from Taung, Sterkfontein, and Makapans (Taung 1, Sts 2, Sts 8, Sts 18, Sts 24, Stw 327, MLD 2) are described. These stages were assessed using the system devised by Demirjian and colleagues and were based on a data set comprising over 350 computed tomographic (CT) scans taken at 1 and 2 mm slice intervals. It is concluded that patterns of dental development may have differed between A. robustus and A. africanus even though the chronology of development (i.e., the length of time for dental development to occur) may have proceeded relatively rapidly in both species. These data provide unique information regarding the timing and pattern of dental maturation in austral‐opithecines and can be used to compare and contrast developmental patterns among early hominids, modern humans, and nonhuman primates.
Perinatal dental development in the chimpanzee (Pan troglodytes)
Authors: Siebert Joseph R. , Swindler Daris R.
Published: February 2006

The synthesis of both ontogenetic and phylogenetic data should provide the ideal explanation of morphologic variation, but for the primate dentition, this has not yet occurred. Information concerning growth and development of primate teeth is lacking, in part because of the paucity of specimens. We have therefore examined the deciduous second molars (dm2) and tooth buds of the permanent first molar (M1) of 12 chimpanzees (Pan troglodytes), aged 6.5 months of gestation to 4 postnatal months. The ordering of cusp calcification was identical to that of other primates. By regression analysis, correlations of mesial and distal widths with buccal, lingual, and mesiodistal lengths were low, most probably because of decreased rates of change (slopes) and the relatively small sample size. Correlations were, however, greater for mandibular than for maxillary dentition and higher for age than for body weight; for both the dm2 and M1, distal moieties increased faster and were more highly correlated with other dental variables and age than were mesial ones. Comparison with data from humans revealed both differences and similarities in the absolute size and growth rate of dental moieties during the perinatal period. As the reasons for ontogenetic variation become understood for individuals, species, and higher taxa, the phylogenetic implications of differential growth should become clearer as well.
On thick and thin enamel in hominoids
Authors: Beynon A. D. , Dean M. C. , Reid D. J.
Published: February 2006

Martin (1983, 1985) reviewed the significance of enamel thickness in hominoid evolution. He studied cut faces of hominoid teeth using the scanning electron microscope and related enamel prism packing patterns to both enamel formation rates and enamel thickness, although he did not present primary data on formation rates, which he summarised as being either “fast” or “slow.” Martin concluded that thick enamel formed at a fast rate represented the ancestral condition in the human and great ape clade. Thin enamel in African apes reflected a secondary reduction in secretion rates, with outer enamel being formed at a slow rate. The present study on ground sections of great ape and human teeth, using polarised light microscopy, was designed to measure the spacing between incremental growth lines in enamel, including striae of Retzius and prism cross striations, to determine rates of enamel formation in hominoids. Measurements on stria spacing showed that striae generally diverged as they passed outwards through enamel in all taxa. Cross‐striation spacings also increased from inner to outer enamel. Secretion rates did not fall into two exclusive categories but varied, giving a spectrum of values generally increasing from within outwards at any one crown level and reducing in cervical enamel. There was no evidence for a reduction in enamel formation rates in outer enamel among African apes. These findings cast doubt on the proposition that the common ancestor of great apes and man had thick enamel formed at a fast rate. It is possible that thin enamel was the primitive condition, in which case thick enamel in humans and in Sivapithecus is derived, suggesting that thick enamel on low cusped teeth evolved on more than one occasion.
Characteristics of hamadryas‐like male baboons living in anubis baboon troops in the Awash hybrid zone, Ethiopia
Authors: Phillips‐Conroy Jane E. , Jolly Clifford J. , Brett Frederick L.
Published: February 2006

In the twenty‐two years since the Awash baboon hybrid zone was first described, about 25–30 hamadryas or hamadryas‐like hybrid males have taken up residence in anubis baboon groups. Most enter as mature adults, though some may immigrate as juvenile followers. Long‐term tracking of known immigrants indicates that they may reside for four years or more in their adopted troop, during which time they establish a series of comparatively short‐term harems, and probably sire hybrid offspring. “Abductions” of anubis females to hamadryas troops, as postulated by early observers, were not seen, though their occurrence cannot be ruled out. Younger, more recent immigrants tend to be “purer” hamadryas in phenotype, perhaps reflecting a more distant origin, or a change in the composition of neighboring hamadryas populations: Coexisting hamadryas and anubis show no signs of reproductive isolation by behavioral barriers, and evidently belong to a single “recognition species”.
Interspecific perspective on mechanical and nonmechanical models of primate circumorbital morphology
Authors: Ravosa Matthew J.
Published: February 2006

Linear dimensions and angular orientations of the browridge, postorbital bar, and postorbital septum were obtained from a representative series of primates and compared with variables associated with several nonmechanical and biomechanical/mechanical models put forward to explain the form and function of the circumorbital region. Analyses of the results indicate that face size is the primary determinant of variation in primate circumorbital morphology. Anteroposterior browridge thickness is correlated with neural–orbital disjunction among anthropoid primates, but not among prosimians. This difference appears related to differences in the construction of the upper face and anterior cranial fossa between prosimians and anthropoids. Little support is demonstrated for the anterior dental loading model of browridge development. Mediolateral postorbital bar width and (to a lesser degree) browridge height are correlated with neurofacial torsion during mastication and variation in masticatory muscle size. These analyses further suggest that since circumorbital structures (especially the browridges) are located the farthest away from the chewing apparatus, they are least affected by masticatory stresses.
Modern human origins in Australasia: Replacement or evolution?
Authors: Kramer Andrew
Published: February 2006

The controversies surrounding the origins of modern humans have spawned two competing hypotheses, namely Replacement and Multiregional Evolution. The first suggests that modern Homo sapiens evolved first in Africa, as late as 140 ka, and subsequently inhabited the balance of the Old World. Conversely, the second hypothesis posits that modern humans evolved principally from local populations of archaic hominids indigenous to the major regions of the Old World.

The hominid mandibular remains (ca. 1 Ma) from Sangiran, central Java, Indonesia, were studied in order to test these hypotheses. Non‐metric comparisons were performed between these fossils and aboriginal H. sapiens from Africa and Australia. The Replacement model would be supported by a unique Afro‐Australian grouping while Multiregional Evolution would be suggested by a Sangiran‐Australasian group which would exclude the modern Africans.

These data support the Multiregional Evolution hypothesis in that a plurality (eight) of the seventeen non‐metric features link Sangiran to modern Australians, while only three exclusively group the humans from Africa and Australia. These results are suggestive of morphological continuity, which implies the presence of a genetic continuum in Australasia dating back at least one million years.
Mechanical implications of chimpanzee positional behavior
Authors: Hunt Kevin D.
Published: February 2006

Mechanical hypotheses concerning the function of chimpanzee anatomical specializations are examined in light of recent positional behavior data. Arm‐hanging was the only common chimpanzee positional behavior that required full abduction of the humerus, and vertical climbing was the only distinctive chimpanzee positional behavior that required forceful retraction of the humerus and flexion of the elbow. Some elements of the chimpanzee anatomy, including an abductible humerus, a broad thorax, a cone‐shaped torso, and a long, narrow scapula, are hypothesized to be a coadapted functional complex that reduces muscle action and structural fatigue during arm‐hanging. Large muscles that retract the humerus (latissimus dorsi and probably sternocostal pectoralis major and posterior deltoid) and flex the elbow (biceps brachii, probably brachialis and brachioradialis) are argued to be adaptations to vertical climbing alone. A large ulnar excursion of the manus and long, curved metacarpals and phalanges are interpreted as adaptations to gripping vertical weight‐bearing structures during vertical climbing and arm‐hanging. A short torso, an iliac origin of the latissimus dorsi, and large muscles for arm‐raising (caudal serratus, teres minor, cranial trapezius, and probably anterior deltoid and clavicular pectoralis major) are interpreted as adaptations to both climbing and unimanual suspension.
Relations between sex hormone level and characters of hair and skin in healthy young men
Authors: Knussmann Rainer , Christiansen Kerrin , Kannmacher Joachim
Published: February 2006

Total testosterone and dihydrotestosterone in blood serum as well as free testosterone in saliva were determined by radioimmunoassay in 110 healthy young men. The results were compared with the development of terminal hair on the trunk and limbs, with the disposition to balding and with the disposition to acne. No significant correlations were found between terminal hair development and absolute androgen levels; however, some significant values were observed in the case of the metabolic rate of dihydrotestosterone/testosterone and the proportion of free to total testosterone. The disposition to balding also correlates positively with the latter ratio. Yet the absolute serum androgen concentrations in men with a disposition to balding is lower than in men with no reduction of scalp hair. The widespread assumption that androgen levels are in general elevated in bald‐trait men must therefore be rejected. In accordance with this finding, men with a disposition to balding are morphologically (with regard to anthropometric measures) no more masculine than those with good scalp hair growth. When body build and age are taken into consideration, the relations between terminal hair and androgen ratio are also problematical. No relationship could be found between acne and androgens. © 1992 Wiley‐Liss, Inc.
Dental and cranial affinities among populations of East Asia and the pacific: The basic populations in East Asia, IV
Authors: Hanihara Tsunehiko
Published: February 2006

The origins of the four major geographical groups recognized as Australomelanesians, Micronesians, Polynesians, and East and Southeast Asians are still far from obvious. The earliest arrivals in Sahulland may have migrated from Sundaland about 40,000–50,000 years B.P. and begun the Australomelanesian lineage. The aboriginal populations in Southeast Asia may have originated in the tropical rain forest of Sundaland, and their direct descendants may be the modern Dayaks of Borneo and Negritos of Luzon. These populations, the so‐called “Proto‐Malays,” are possible representatives of the lineage leading to not only modern Southeast Asians, but also the Neolithic Jomon populations in Japan. The present study suggests, moreover, that the Polynesians and western Micronesians have closer affinities with modern Southeast Asians than with Melanesians or Jomonese. © 1992 Wiley‐Liss, Inc.
Negritos, Australian Aborigines, and the “proto‐sundadont” dental pattern: The basic populations in East Asia, V
Authors: Hanihara Tsunehiko
Published: February 2006

Five evolutionarily significant dental traits were identified from a B‐square distance analysis of nine crown characters recorded for several populations of East Asia and Oceania. Intergroup variation in these traits distinguishes three major divisions of the Mongoloid dental complex: sundadonty, sinodonty, and the dental pattern of Australian Aborigines. The Australian crown features may be characterized as having high frequencies of evolutionarily conservative characters. Negritos, one of the probable representatives of indigenous inhabitants of Southeast Asia who may have shared a common ancestor with Australians, possess the more derived sundadont dental pattern. As far as the five crown traits treated here are concerned, Australian dental features may be described as conforming to a “proto‐sundadont” dental pattern, applying Turner's terminology. This pattern may represent a microevolutionary step prior to the emergence of the sundadont and sinodont patterns. © 1992 Wiley‐Liss, Inc.
Positional behavior and body size of arboreal primates: A theoretical framework for field studies and an illustration of its application
Authors: Cant John G. H.
Published: February 2006

The rationale for most field studies of the positional behavior of arboreal primates has been the need to document natural behaviors quantitatively in order to infer the functional significance of morphological configurations. This focus on interactions of morphology with behavior is justifiable, but there exists another important level of biological relationships, that of the animal with its structural habitat, which it must negotiate to find food and avoid being preyed on. Recently it has become apparent that body size is likely to affect relationships of positional behavior with habitat structure, as well as with morphology. Here I offer a framework for research on functional relationships of positional behavior, body size, and habitat structure, with the ultimate objective of elucidating the aptive significance of the great diversity exhibited by arboreal primates. This approach specifies several distinct problems that animals solve, and indicates how research might be directed at revealing the relative effectiveness with which different primates solve them. A preliminary application of the framework examines sympatric north Sumatran primates. © 1992 Wiley‐Liss, Inc.
Effects of demographic and ethnohistorical factors on average heterozygosities of South Amerindians
Authors: Aguiar Gilberto F. Souza
Published: February 2006

Recent investigations have shown that average within‐Tupi genetic distances differ from within‐Carib distances, which is possibly due to differences in effective size of the populations belonging to these two linguistic stocks of South American tribes. The aim of this paper is to verify the influence of demographic factors and of interpopulation contacts on the degree of intragroup genetic variability of 18 South American native groups (eight Carib, seven Tupi, and three Gě). The mean per locus per individual heterozygosity (Hm) was studied for seven polymorphic systems and the distance from the centroid, rii on Hm was evaluated with regression analysis according to Harpending and Ward's model. Data on intergroup contacts among the populations since the end of the eighteenth century were collected from an extensive review of the ethnohistorical literature. The level of Hm of the three linguistic stocks did not differ; which suggests a homogeneous within‐group variation for these groups. In addition, there was no association between gene diversity and population size. On the other hand, demographic size correlated with rii, which suggest that gene frequencies in groups of larger populations more closely resemble the average gene frequencies of native South Americans. Values of rii differed between the stocks, and the average distance from the centroid of the Carib was about 2.6 times greater than that of the Tupi, in accordance with previous genetic distance analysis. It should also be emphasized that there was an important correlation between mean heterozygosity and the degree of historical intertribal contacts. This constitutes a particularly significant finding, suggesting the basic role of intertribal gene flow of the past to centuries on the level of present genetic variability of south American tribes. © 1992 Wiley‐Liss, Inc.
Muscle force recruitment and biomechanical modeling: An analysis of masseter muscle function during mastication in Macaca fascicularis
Authors: Hylander William L. , Johnson Kirk R. , Crompton A. W.
Published: February 2006

The main purpose of this study is to test the hypothesis that as subjects chew with increasing levels of force, the ratio of the working‐ to balancing‐side jaw‐muscle force (W/B) decreases and begins to approach 1.0. We did this by analyzing relative masseter force in Macaca fascicularis using both strain gage and surface electromyographic (EMG) techniques. In addition, we also analyzed: 1) the relationship between jaw position using cineradiographic techniques and relative masseter force, 2) the timing differences between relative masseter force from the working and balancing sides, and 3) the loading and unloading characteristics of the masseter muscle.

Our findings indicate that when macaques increase the amount of overall masticatory force during chewing, the W/B ratio for masseter force frequently (but not always) decreases and begins to approach 1.0. Therefore, our working hypothesis is not completely supported because the W/B ratio does not decrease with increasing levels of force in all subjects. The data also demonstrate timing differences in masseter force. During apple‐skin mastication, the average peak masseter force on the working side occurs immediately at or slightly after the initial occurrence of maximum intercuspatiori, whereas the average peak masseter force on the balancing side occurs well before maximum intercuspation. On average, we found that peak force from the balancing‐side masseter precedes the working‐side masseter by about 26 msec. The greater the asynchrony between working‐ and balancing‐side masseter force, the greater the difference in the relative magnitude of these forces. For example, in the subject with the greatest asynchrony, the balancing‐side masseter had already fallen to about one‐half of peak force when the working‐side masseter reached peak force.

Our data also indicate that the loading and unloading characteristics of the masseter differ between the working and balancing sides. Loading (from 50 to 100% of peak force) and unloading (from 100 to 50% of peak force) for the balancing‐side masseter tends to be rather symmetrical. In contrast, the working‐side masseter takes much longer to load from 50 to 100% of peak force than it does to unload from 100 to 50% of peak force. Finally, it takes on average about 35 msec for the working‐side zygoma and 42 msec for the balancing‐side zygoma to unload from 100 to 50% of peak force during apple‐skin mastication, indicating that the unloading characteristics of the macaque masseter during mastication closely approximates its relaxation characteristics (as determined by muscle stimulation). © 1992 Wiley‐Liss, Inc.
Systematics and body size: Implications for feeding adaptations in new world monkeys
Authors: Ford Susan M. , Davis Lesa C.
Published: February 2006

The relationship between body size and feeding ecology is well established for primates. It is argued that the evolutionary history of modern New World monkeys and, in particular, the path to attainment of current body size is significant in understanding the similarities and differences between dietary strategies and other ecological parameters of similar‐sized monkeys. Current interpretations of New World monkey evolutionary relationships are reviewed. Based on a synthesis of available body weights and the assumption that the earliest New World monkeys weighed close to 1 kg, similar to modern Aotus and Callicebus, predicted patterns of body size change in each lineage are given. Restrictions on directions of body size change in primates are discussed, and it is shown that “Stanley's Rule” offers a good explanation for differing body size ranges in New and Old World anthropoids. Predicted ecological correlates to body size drawn from the mammalian literature are offered and tested using data on New World monkeys, which show some concurrence and several interesting departures from predicted patterns. Sexual dimorphism in body weight of New World monkey species is reviewed, based on the new summary of body weight data given. © 1992 Wiley‐Liss, Inc.
Vertical clinging, small body size, and the evolution of feeding adaptations in the Callitrichinae
Authors: Garber Paul A.
Published: February 2006

Primates of the subfamily Callitrichinae (Callimico, Callithrix, Leontopithecus, and Saguinus) are small‐bodied New World monkeys (105–700 g) possessing clawlike nails on all manual and pedal digits excluding the hallux. Specialized nails in these genera serve a critical function in feeding by enabling tamarins and marmosets to cling to trunks and other large vertical supports while exploiting food resources. Within the subfamily, there is evidence of at least four distinct large‐branch feeding patterns. These include (1) seasonal exudate feeding and occasional trunk foraging (many Saguinus spp.); (2) exploitation of bark surface insects and the use of trunks as a platform to locate terrestrial prey (Saguinus fuscicollis, S. nigricollis, and Callimico); (3) manipulative foraging and bark stripping to locate concealed insects and small vertebrates (Leontopithecus); and (4) tree gouging and year‐round exudate feeding (many Callithrix). Large‐branch feeding and the use of vertical clinging postures appear to be a primary adaptation among virtually all callitrichines, distinguishing them ecologically from other platyrrhine taxa. Given the anatomy and behavior of extant callitrichines, Saguinus appears to be the most ecologically generalized member of this subfamily, and species of this genus may provide useful models for reconstructing the feeding and foraging adaptations of early callitrichines. © 1992 Wiley‐Liss, inc.
Morphological and behavioral adaptations for foraging in generalist primates: The case of the cebines
Authors: Janson Charles H. , Boinski Sue
Published: February 2006

In addition to being frugivorous, Cebus and Saimiri stand out among the New World primates of similar body size in being heavily dependent on animal matter for protein (faunivory). A detailed description of the morphology and behavior of the two genera is presented with the object of evaluating the interaction and respective contributions of morphological and behavioral adaptations to foraging patterns. Our conclusions include the following: First, body size is extremely important in explaining the observed variation in diet. Second, the emphasis on faunivory is facilitated more by behavioral than by morphological specialization. Third, whatever morphological specializations are present, particularly in Cebus, are probably favored by diet at the most food‐depauperate time of year. Fourth, although morphology may well reveal what a primate may potentially eat, to map this potential onto actual diet requires a detailed knowledge of its natural ecosystem. Finally, we consider whether the behavioral data support the tenuous morphological evidence for grouping Cebus and Saimiri within the clade Cebinae. © 1992 Wiley‐Liss, Inc.
Dermatoglyphic variation among Finno‐Ugric speaking populations: Methodological alternatives
Authors: Jantz R. L. , Brehme H. , Eriksson A. W.
Published: February 2006

Utilization of dermatoglyphics for population studies is apparently increasing, but methods vary widely among investigators. We investigate how different types of dermatoglyphic data can affect estimates of biological distance among Finno‐Ugric speaking populations. Dermatoglyphic distances were calculated using the following categories of traits: 1) Finger ridge‐counts (radial and ulnar count for each digit), 2) finger ridge‐counts (largest count for each digit), 3) finger pattern types, 4) palm ridge‐counts, 5) palm patterns, and 6) main‐line terminations. In addition, we compare our distances with those of Heet, which rely heavily on summary characters. Distances are evaluated by comparing them to each other and to language and geographic distances.

There is considerable variation in the pattern of relationships resulting from the different variable sets. Finger variables, whether ridge‐counts or pattern classifications, agree well with each other. Palm patterns, main‐lines, and finger variables show moderate agreement with each other, while palm ridge‐counts agree poorly with all variable sets except main‐lines. Heet's distances agree poorly with all other dermatoglyphic distances. Finger patterns and main‐lines are most closely related to language distances, after controlling for geography, while correlations with geography generally disappear after controlling for language. Heet's distances have weak associations with language and geography. Finger variables and palm main‐lines yield results which agree best with historical relationships among Finno‐Ugric populations. Our results make it very clear that utilization of dermatoglyphics in population studies requires careful consideration of methods, and that summary measures of quantitative or qualitative data should be used with caution. © 1992 Wiley‐Liss, Inc.
Can we really walk straight?
Authors: Uetake Teruo
Published: February 2006

Twenty healthy men were asked to walk as straight as possible to a target 60 m away at normal speed. A series of footprints was recorded for each subject by having him wear socks soaked with red ink and walk on white paper fixed flat to the floor. Fourier analysis was applied to determine whether the subjects actually were able to walk straight, and the results revealed that all walked in a sinuous line rather than a straight line. Periodicity and amplitude of the meandering differed from subject to subject. These facts suggest that none of us can walk in a strictly straight line; rather, we meander, primarily due to a slight structural or functional imbalance of our limbs, which produces a gait asymmetry, and secondarily due to feedback from our sense of sight, which acts to correct the shifted walking course. © 1992 Wiley‐Liss, Inc.