bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural control of quadrupedal and bipedal stance: Implications for the evolution of erect posture
Authors: Dunbar Donald C. , Horak Fay B. , Macpherson Jane M. , Rushmer Donald S.
Published: August 2005

The transition among hominids from quadrupedalism to bipedalism resulted in modifications in their musculoskeletal morphology. It is unclear, however, whether changes in the circuitry of the CNS were also necessary in order to accommodate the unique balance requirements of twolimb support. This study addresses the issue of modifications in control strategies by investigating the rapid, automatic postural responses of feline and human subjects to sudden disturbances of balance in the anteroposterior (AP) direction while they stand quadrupedally and bipedally on movable platforms. Postural responses are characterized in terms of segmental adjustments, generated AP shear forces, and electromyographic activity. Feline and human subjects correct posture similarly when standing quadrupedally. Furthermore, both species correct stance primarily with their hindlimbs and use their forelimbs as supportive struts. In contrast, both species use completely different correctional strategies when standing bipedally. Morphological restrictions, however, prevent cats from adopting the pillar‐like plantigrade posture of human beings. Thus, the correctional strategies of bipedal cats are distinct from those of bipedal human subjects. It is concluded that 1) automatic postural response patterns of quadrupedal Felis and bipedal Homo reflect the different biomechanical characteristics of the initial postures rather than species differences in CNS circuitry controlling stance; 2) hindlimb‐dominated posture control is probably a common and relatively ancient pattern; and 3) reorganization of hominid CNS circuitry was probably unnecessary because hindlimb control was already a feature of the system.
Architectural and histochemical diversity within the quadriceps femoris of the brown lemur (Lemur fulvus)
Authors: Anapol Fred C. , Jungers William L.
Published: August 2005

Physiologically related features of muscle morphology are considered with regard to functional adaptation for locomotor and postural behavior in the brown lemur (Lemur fulvus). Reduced physiological cross‐sectional area, estimated maximum excursion of the tendon of insertion, length of tendon per muscle fasciculus, and areal fiber type composition were examined in the quadriceps femoris in order to assess the extent of “division of labor” among four apparent synergists.

Each of these four muscles in this prosimian primate displays a distinguishing constellation of morphological features that implies functional specialization during posture and normal locomotion (walk/run, galloping, leaping). Vastus medialis is best suited for rapid whole muscle recruitment and may be reserved for relatively vigorous activities such as galloping and leaping (e.g., small cross‐sectional area per mass, long excursion, predominance of fast‐low oxidative fibers, relatively little tendon per fasciculus). In theory, rectus femoris could be employed isometrically in order to store elastic strain energy during all phasic activities (e.g., large cross‐sectional area per mass, short excursion, predominance of fast‐high oxidative fibers, large amount of tendon per fasciculus). Vastus intermedius exhibits an overall morphology indicative of a typical postural muscle (e.g., substantial cross‐sectional area, short excursion, predominance of slow‐high oxidative fibers, large amount of tendon per fasciculus). The construction of vastus lateralis reflects an adaptation for high force, relatively high velocity, and resistance to fatigue (e.g., large cross‐sectional area, long excursion, most heterogeneous distribution of fiber types, large amount of tendon per fasciculus); this muscle is probably the primary contributor to a wide range of locomotor behaviors in lemurs.

Marked dramatic architectural disparity among the four bellies, coupled with relative overall fiber type heterogeneity, suggests the potential for exceptional flexibility in muscle recruitment within this mass. One interpretation of this relatively complex neuromuscular organization in the brown lemur is that it represents an adaptation for the exploitation of a three‐dimensional arboreal environment by rapid quadrupedalism and leaping among irregular and spatially disordered substrates.
Density‐dependent migration and human population structure in historical Massachusetts
Authors: Relethford John H.
Published: August 2005

Studies of population structure often focus on the effects of population size and migration rates on genetic variation. Few studies, however, have investigated the relationship between these two factors. The purpose of this paper is to determine the extent to which migration (and gene flow) is density‐dependent (that is, affected by population size) for populations in historical Massachusetts. Data from 4,859 marriage records were analyzed from four populations in north‐central Massachusetts during the time period 1741 to 1849. These data were placed into 29 samples defined in terms of population and time cohort. Within each cohort the overall exogamy rate was computed along with three estimates of gene flow based on marital migration: local migration (k), long‐distance migration (m), and effective migration rate (me). Three samples show unusually low rates that reflect the history of settlement. Regression analyses were used with the remaining samples, and they show nonlinear density‐dependent migration that is unrelated to temporal trends. Migration is highest in samples with small population sizes (< 800) and large population sizes (> 1,600). Migration is lowest in medium‐sized populations. Two processes are suggested to explain this curvilinear relationship of migration and population size. In small populations, the lack of suitable potential mates and/or availability of settled land leads to an increase in migration into the population. As population size, increases, this migration decreases. After populations reach a certain size, migration increases again, most likely reflecting the economic pull of larger populations. These patterns could act to enhance, or counter, genetic drift, depending on the direction of density dependence.
Possible influence of age on the expression of the heterozygous cerumen phenotype
Authors: Petrakis Nicholas L. , Wiesenfeld Stephen L. , Flander Louisa
Published: August 2005

The relationship of cerumen (earwax) phenotype and age was examined in 2,618 women. An increasing proportion of white women with dry or unclassifiable cerumen was found with advancing age, ranging from 2.0% in women under 30 years to 13.3% in women 70 years and older. No statistically significant change with age was found in other racial groups. It is suggested that the increase of dry or unclassifiable cerumen in white women represents a change in the expressivity of alleles that determine cerumen type occurring with advancing age in women who are heterozygous for the trait.
Effects of interracial crosses on cephalometric measurements
Authors: Chung C. S. , Runck D. W. , Bilben S. E. , Kau M. C. W.
Published: August 2005

The effects of race and interracial crossing were examined on six cephalometric measurements among 9, 912 schoolchildren in Hawaii. The measurements studied were face height, bizygomatic diameter, bigonial diameter, head breadth, head length, and cephalic index. Racial effects were studied in terms of general racial effect, maternal effect, and hybridity and recombination effects based on a model of diallel cross. Generally, Chinese, Japanese, Koreans, and Filipinos were characterized by longer lateral and smaller anterior‐posterior dimensions relative to Caucasians. Maternal effects appeared to be present in the measures of lateral dimension. No clear effects of hybridity and recombination were seen except for bizygomatic diameter, which appears to behave as a partial dominant trait. The racial mean of bizygomatic diameter, or the ratio of this measure to head length, were found to have a relationship with the racial incidences of cleft lip with or without cleft palate.
The phylogenetic and taxonomic status of Pan paniscus: A chromosomal perspective
Authors: Stanyon Roscoe , Chiarelli Brunetto , Gottlieb Karen , Patton William H.
Published: August 2005

The taxonomic status and phylogenetic position of the bonobo or pygmy chimpanzee continues to be debated. In this report we examined the phylogenetic position and taxonomic status of the pygmy chimpanzee by a three‐way comparison of the banded chromosomes of humans, Pan troglodytes and Pan paniscus. The evaluation pays particular attention to distinguishing ancestral versus derived chromosomes in order to determine the direction of the chromosomal differences found between these three taxa. P. paniscus and P. troglodytes are shown to share a number of derived chromosomal changes indicative of a probable extensive period of common evolution after the divergence of the humans. The karyological evidence also demonstrates that the pygmy chimpanzee is most likely a valid species, and that it is also the most chromosomally specialized of the three taxa examined. Therefore, from the chromosomal perspective, the pygmy chimpanzee is not the best model for the last common ancestor of both humans and African apes. The chromosomal data also suggest that all the African apes have evolved more from this last common ancestor than is generally considered.
Sexual dimorphism in the emergence of deciduous teeth: Its relationship with growth components in height
Authors: Tanguay Richard , Buschang P. H. , Demirjian Arto
Published: August 2005

Sexual dimorphism in the emergence of the deciduous dentition of French‐Canadian children may be explained by differences in recumbent length. Relative to the chronological age scale, boys are longer and their teeth emerge earlier than girls. Recumbent lengths attained at the exact age of emergence, as estimated by fifth‐order polynomials fitted to each subject's serial data, are comparable between the sexes. Multi‐ and univariate analyses of variance show no significant sex differences in the lengths attained at the age of emergence of the deciduous teeth. These findings suggest that clinical standards for emergence of deciduous teeth scaled relative to length rather than chronological age are more accurate and efficient.
National Science Foundation support of physical anthropology research
Authors: Yellen John E. , Zeleznik Scott
Published: August 2005

Awards by the National Science Foundation Anthropology Program are analyzed and patterns of overall NSF support, proposal submissions, and success rates discerned. An attempt is made to explain these.
Pliocene hominid partial mandible from Tabarin, Baringo, Kenya
Authors: Ward Steven , Hill Andrew
Published: August 2005

Sediments in the Tugen Hills, west of Lake Baringo, Kenya, form one of the best fossiliferous successions known in Africa spanning the period from 14 my to less than 4 my. Hominoid fossils have previously been recovered from a number of localities in the region. We describe here a new hominid mandible (KNM‐TH 13150) from the site of Tabarin, in the Chemeron Formation. Isotopic determinations on a tuff below the fossiliferous horizon gives dates of 4.96 my and 5.25 my. The associated fauna is consistent with these results and independently suggests a minimum age for the specimen of 4.15 my. Although fragmentary, the preserved morphology of the Tabarin mandible is consistent with the diagnosis of the Pliocene hominid Australopithecus afarensis. It can be distinguished from all other currently recognized hominoid taxa.
Tissue identification and histologic study of six lung specimens from Egyptian mummies
Authors: Walker Roxie , Parsche Franz , Bierbrier Morris , McKerrow James H.
Published: August 2005

Twenty‐eight specimens obtained either from organ bundles in the body cavities of intact mummies, from damaged mummies, or from isolated canopic jars were examined for tissue identification and histopathologic study. The methods of rehydration and fixation were optimized by application to 40 dehydrated modern samples before studies of mummified tissue were undertaken. The tissue of origin could be definitely identified in 24 of the 28 specimens. Even small fragments obtained from isolated canopic jars proved suitable for histologic study. Six lung specimens were selected for more detailed study. All six showed focal deposition of anthracotic pigment. Electron diffraction and electron microprobe analysis of one of the small, polarizable crystals associated with the anthracosis indicated a mineral content of silica, aluminum, and iron. Two specimens showed focal areas of calcification consistent with old mycobacterial disease. Other histopathologic findings included evidence of pulmonary edema, emphysema, and pneumonia.
Longitudinal study of dental arch relationships in Australian Aboriginals with reference to alternate intercuspation
Authors: Brown Tasman , Abbott Amanda H. , Burgess Vivian B.
Published: August 2005

The patterns of age change in dental arch breadths and depths were studied longitudinally in Australian Aboriginals, 92 males and 68 females. Three types of change in relative arch dimensions were recognized: a divergent pattern in which the differences between maxillary and mandibular dimensions increased with age, a convergent pattern in which the differences decreased, and a parallel pattern in which the arch differences remained metrically stable. The feature that best distinguished the Aboriginals from Caucasian groups was the high frequency of subjects, 71% of males and 40% of females, who showed a divergent growth pattern. The association between divergent growth in arch breadths and the development of alternate intercuspation, which is characterized by an inability to occlude the teeth on both sides of the arch at the same time, is discussed.
Jugular foramen and mylohyoid bridging in an Asian Indian population
Authors: Sawyer Danny R. , Kiely Michael L.
Published: August 2005

The incidence of jugular foramen and mylohyoid groove bridging was studied in a population of East Asian Indian skulls (125 males and 109 females). The criteria of Dodo (J. Anat. 144:153–165, 1986) was used in the identification of a jugular bridge. There was an overall incidence of 8.1% in jugular foramen bridging, with males showing a higher rate, though the difference did not reach statistical significance. The right side showed a statistically significant greater occurrence than the left, and the trait tended to be associated between sides. The overall incidence of mylohyoid bridging was found to be 2.6%, with no difference observed between the sexes. This frequency is less than the values reported for other Asian Indian studies. Studies concerned with the incidences of nonmetric traits such as bony bridging may be useful in population studies especially when utilized in combination, thereby enhancing the value of each trait as an anthropological tool.
Comparative study of mesiodistal crown diameters and arch dimensions between indigenous British and Pakistani immigrant populations
Authors: Radnzic D.
Published: August 2005

Over the last two decades, the United Kingdom has seen an increase in the number of immigrants from the Indian subcontinent, mainly Pakistan. The amount of information that is available regarding parameters such as mesiodistal crown diameters and dental arch dimensions is, however, somewhat limited for this population.

An investigation was carried out to compare corresponding mesiodistal crown diameters and arch dimensions between samples of the indigenous British population in Leeds (England) and the Pakistani immigrant population living in Rochdale (England). Measurements were taken from dental casts.

The results showed that there were no significant differences between the two ethnic groups in corresponding mesiodistal crown diameters or arch dimensions. Data are provided for the Pakistani immigrant population in Britain.
Effect of altitude on the lung function of high altitude residents of European ancestry
Authors: Greksa Lawrence P. , Spielvogel Hilde , Paz‐Zamora Mario , Caceres Esperanza , Paredes‐Fernández Luis
Published: August 2005

The forced vital capacity (FVC), forced expiratory volume in one second (FEV), and ratio of FEV to FVC (%FEV) of 161 male and 158 female youths of European ancestry who were born at high altitudes and who were residing in La Paz, Bolivia (average altitude of 3,600 m) were examined and compared with those for lowland Europeans and highland Aymara Amerindians. FVC and FEV were significantly larger (p < .001) in the La Paz Europeans than in two lowland control samples of European ancestry, with the relative differences between samples varying from small (1.5–4.1%) to moderate (7.7–11.9%). It could not be determined whether the enhanced lung volumes of the La Paz European children were acquired through an accelerated development of lung volumes relative to stature during adolescence, as is the case for Amerindian highlanders. After controlling for body and chest size, FVC and FEV were significantly smaller in the La Paz Europeans than in highland Aymara (p < .001), suggesting that the lung volumes of the Aymara are influenced by factors other than simply growth and development at high altitude. Finally, as found in Amerindians, chest size is an important determinant of intra‐individual variation in lung function among highland Europeans.
A principal components analysis of human odontometrics
Authors: Harris Edward F. , Bailit Howard L.
Published: August 2005

It has long been recognized that tooth crown diameters in hominoids are all positively intercorrelated one with another. This study reports on sex‐specific correlation matrices derived from 2,650 individuals from the Solomon Islands, Melanesia. Mesiodistal and buccolingual diameters of all permanent teeth from one side are used, excluding third molars. Analysis discloses significant sex dimorphism in the strengths of the intercorrelations, with females being better integrated. Principal components analysis (PCA) provides an objective means of data reduction (shown here to be preferable to simple size summation methods) and decorrelation of the resulting linear combinations. Four components are extracted (with results being virtually identical in the two sexes) and arguments are put forth that varimax rotation to “a simpler solution” may be counterproductive. Before rotation, the four components are 1) overall size, 2) buccolingual widths contrasted with mesiodistal lengths, 3) anterior (I,C) contrasted with posterior (P,M) teeth, and 4) premolars contrasted with molars. Most of the explained (shared) variance (63%) extracted by PCA is in overall size of the dentition. There is a strong urge to view the results of these principal components analyses as reflective of biologically and genetically meaningful entities.
Dermatoglyphic variation and weight and length at birth
Authors: Loesch Danuta Z. , Przybyla Beata
Published: August 2005

Relationships between dermatoglyphic variables, including finger ridge counts and finger, palmar, and plantar pattern intensities, and weight and length at birth, were tested in a sample of 184 boys and 202 girls from Warsaw schools. No convincing evidence for such relationships has been obtained from the results of correlations and one‐way analysis of variance, although there are indications that some palmar traits may be related to length at birth in females.

The data agree with the common belief that birth weight and birth length are mainly determined by influences operating in later stages of pregnancy, that is, after the 20th gestational week.
Diachronic patterns of change in structural properties of the femur in the prehistoric American Southwest
Authors: Brock Sharon L. , Ruff Christopher B.
Published: August 2005

Diachronic patterns of change in the femoral diaphysis are examined in archaeological skeletal samples from the American Southwest. Three cultural periods differing in subsistence‐settlement strategies are represented: Early Villages (A.D. 500–1150), Abandonments (A.D. 1150–1300), and Aggregated Villages (A.D. 1300–1540). Relevant properties of cross‐sectional geometry and bone density were obtained using computerized tomography. Temporal trends in geometry suggest that activity levels increased between Early Villages and Abandonments, then declined during Aggregated Villages. In both sexes, femoral shape became more circular, and bending stresses were reduced in the a‐p plane through time. Compared to the other periods, bone density was the lowest during Abandonments in both sexes. The reduction in bone density may reflect declining nutritional quality through time that was especially poor during the Abandonments period. Patternings in sexual dimorphism suggest that Abandonments males may have been more sensitive to nutritional stress than contemporary females.
Scaling of growth and life history traits relative to body size, brain size, and metabolic rate in Lorises and Galagos (Lorisidae, primates)
Authors: Rasmussen D. Tab , Izard M. Kay
Published: August 2005

A broad range of variation in body size, brain size, and metabolic rate occurs within the primate family Lorisidae, thus providing an opportunity to examine the relationship of these three parameters to variation in growth and life history traits. Data on adult body weight, gestation length, lactation length, age at first estrus, litter size, and growth parameters were collected from a captive colony of four lorisid species, Loris tardigradus, Nycticebus coucang, Galago crassicaudatus, and G. senegalensis. The data presented here constitute the most complete life history information available for these poorly understood prosimian species. Correlation and allometric analyses were performed to determine the relationships between variables. Among the lorisids studied, adult body weight, adult cranial capacity, and relative cranial capacity did not predict variation in life history traits. Adult basal metabolic rate predicted most of the variability in gestation length, lactation length, and growth parameters. Lorisines differ from similarly sized galagines in having lower basal metabolic rates, slower growth rates, slower developmental rates, and smaller litter sizes, resulting in reduced reproductive potential. This may be a consequence of lorisine adaptation to a diet of toxic insects. Metabolic rate and diet may be among the most important parameters to examine in any study of life history evolution.
Genetic markers in the Hindu and Muslim Gujjars of Northwestern India
Authors: Balgir R. S. , Sharma J. C.
Published: August 2005

A comparative study of serogenetic markers was carried out among the Hindu and Muslim Gujjars from Northwestern India. From each isolate of Gujjars, 200 adult couples were examined for the A1A2BO and Rhesus blood groups, ABH secretion, the serum proteins haptoglobins, transferrins, and albumins, and 200 male subjects were examined for glucose‐6‐phosphate dehydrogenase enzyme deficiency. The study showed that the Muslim Gujjars differ significantly from their counterpart, the Hindu Gujjars. The differentiation that has occurred among the Muslim Gujjars may be attributed to their geographical dispersal in diverse habitats, the inflow of genes from Islamic invaders as well as non‐Islamic surrounding populations, the inbreeding effect, and the comparative breeding isolation. The genetic affinities of the Hindu Gujjars with the Jats and Rajputs provide strong evidence for their common ethnic origin and probably their recent fissioning owing to biosocial practices and occupational patterns. The computed genetic distance matrix shows diversity of Ahirs from all the concerned population groups.
Odontometric profile of a prehistoric southeastern Florida population
Authors: Yaşar İşcan Mehmet
Published: August 2005

This study analyzes and compares the dental size variation and sexual dimorphism of the Highland Beach Mound people, a late southeastern prehistoric aboriginal Florida population (ca. 800–1200 AD) with a somewhat earlier midwestern group (ca. 200–800 AD) and an Archaic sample (ca. 4160–2558 BC). The lengths and breadths of maxillary and mandibular permanent teeth of 99 individuals were measured, and crown surface areas were calculated for the molars. Results indicated that there was little sexual dimorphism. Only the mesiodistal dimensions of the upper P2 and lower C were significantly different at the P < 0.05 level. In terms of dental size, what appears to be a chronologically based reduction in most points of comparison was seen in all three groups, with the exception of the molars, which were larger in the Highland Beach sample than in the earlier Schultz Mound.
Caries prevalences among geochemical regions of Missouri
Authors: Hildebolt C. F. , Elvin‐Lewis M. , Molnar S. , McKee J. K. , Perkins M. D. , Young K. L.
Published: August 2005

Our objectives were to determine how the prevalences of caries in elementary school children vary between geochemically defined regions of the state of Missouri and to compare this variation with that found for prehistoric Missouri inhabitants (Hildebolt et al.: Am. J. Phys. Anthropol. 75:1–14, 1988). Caries data on 6,584 school children were used in the study of second and sixth graders drinking optimally and suboptimally fluoridated water. Geochemical regions were based on maps recently published by the United States Geological Survey. Differences in mean caries scores and proportions of children with caries were tested by analysis of covariance, analysis of variance, Student t, and chi‐squared tests. We found that caries prevalences do vary between the geochemical regions of the state. In the total sample, however, there were no significant differences between those children drinking optimally fluoridated water and those drinking suboptimally fluoridated water. We conclude that there is variation in caries rates among geochemically defined regions of the state and that geochemical factors associated with young parent materials may be antagonizing the action of fluoride.
Morphological and metrical comparison of San and Central Sotho dentitions from southern Africa
Authors: Haeussler A. M. , Irish J. D. , Morris D. H. , Turner C. G.
Published: August 2005

Comparative morphological and metrical study of San and Central Sotho dentitions indicates that the teeth of the two samples are significantly different from one another. The San dental complex contains traits that add mass to the occlusal surface of microdontic dentitions: moderate low‐grade UI1 (13.5%) and UI2 shoveling (24.7), high Bushman canine (43.1%), fairly low UM2 hypocone reduction (23.3%), high UM2 cusp 5 (55.6%), high LM1 cusp 7 (35.2%), LM1 distal trigonid crest (7.1%), LM2 deflecting wrinkle (5.3%), lack of reduction of LM1 and LM2 cusp number, in the presence of very low UM1 Carabelli's trait (6.7%) and high LM2 Y‐groove (86.3%). Culturally, males occasionally exhibit filed UI1 and females are missing LI1. Conversely, mesodontic Central Sotho dentitions display a more simplified morphology, with the exception of moderately high incidence of UM1 Carabelli's trait (41.0%) and very high LM1 cusp 7 (71.3%). Discriminant analysis of mesiodistal and buccolingual diameters and tooth crown surface area data for the left maxillary teeth supports classification of San dentitions as microdont and Central Sotho dentitions as mesodont. Additionally, metrical analysis indicates that San teeth are more sexually dimorphic than are those of Central Sotho.
The calcaneus of Australopithecus afarensis and its implications for the evolution of bipedality
Authors: Latimer Bruce , Lovejoy C. Owen
Published: August 2005

Calcanei from African apes, modern humans, and Australopithecus afarensis are compared to investigate the anatomical and mechanical changes that occurred in this bone as a result of the transition to terrestrial bipedality. Features analyzed include the cross‐sectional area and volume of the calcaneal tuber, the geometry and orientation of the articular surfaces, and the surface topography of the calcaneal corpus. Calcaneal morphology is unequivocal in its partitioning of quadrupedal pongids and bipedal hominids.
Creeping patterns of human adults and infants
Authors: Sparrow W. A.
Published: August 2005

The patterns of swing and support for the hands‐and‐feet or hands‐and‐knees gaits (creeping) of human adults and infants are compared based on data from a number of studies. Human infants show considerable variability in their creeping gait patterns, whereas adult patterns are less variable and fairly consistent after a few minutes of practice. Creeping on hands‐and‐knees appears to dictate a gait pattern characteristically different from creeping on hands‐and‐feet. The highly inefficient nature of adult creeping supports the view that our early hominid ancestors were poorly adapted to quadrupedal locomotion. Data obtained from high‐speed film analysis of human creeping patterns show that the number of foot lengths per stride in creeping is about twice that for normal upright walking at the same speed. The support pattern of human creeping is different from that of nonhuman primates. These findings are discussed in the context of debate concerning the origin of the Laetoli hominid footprints and the knuckle‐walking hypothesis.
Small tooth sizes in a nineteenth century South Carolina plantation slave series
Authors: Harris Edward F. , Rathbun Ted A.
Published: August 2005

Sub‐Saharan African (and derived) populations typically exhibit larger mean tooth crown diameters than whites in spite of considerable population variability. We report on a 19th century series of American black slaves from a single cemetery near Charleston, South Carolina, that possessed notably smaller crown sizes. Analysis identifies a characteristic set of differences compared to caucasians, including retention of large maxillary lateral incisors and disproportinately large premolars and molars. Regression of principal components scores (derived from the mesiodistal diameters) on the sum of all diameters (used here as a measure of overall tooth mass) confirms a basic ethnic difference between black and white odontometrics: significantly more of the tooth mass is apportioned to the cheek teeth (premolars, molars) in blacks than whites. The difference (expressed as residuals from linear regression on tooth mass) holds for the several groups assessed here despite considerable intergroup variability in tooth sizes. Potential explanations for the notably small diameters of this plantation series are speculative, but may involve kin‐based divergences and/or reflect the natural intergroup differences extant in the African slave sources.
Research on the Efe and Lese populations of the Ituri forest, Zaire
Authors: Bailey Robert C. , Devore Irven
Published: August 2005

Since 1980, as part of the Ituri Project, researchers have been studying numerous aspects of the biology, health, economy, and social relations of Efe (Pygmies) and Lese villagers living in the Ituri Forest region of north‐eastern Zaire. The Efe are seminomadic people who hunt and gather forest resources for their own consumption and for exchange with sedentary subsistence farmers. The Lese are Sudanic‐speaking subsistence farmers who practice shifting slash‐and‐burn horticulture and live in semipermanent villages. Relations between the Efe and Lese have been close for many generations and extend beyond economic exchange to include most aspects of ritual and social life.

This paper serves as an introduction to five subsequent papers that report findings from research on these two forest‐living populations. It provides background information concerning the ecology and history of human occupation of the Ituri region of central Africa; it describes the study area and the study populations; it discusses how the annual subsistence cycles of the Efe and Lese relate to rainfall and food availability; and it provides further information concerning Ituri Project research during the last 7 years.
Paleoepidemiology of a central California prehistoric population from CA‐Ala‐329: Dental disease
Authors: Jurmain Robert
Published: August 2005

Ala‐329 is a prehistoric central California site located on the southeastern margin of San Francisco Bay, dating from approximately 500 AD up to pre‐European contact. A large earth mound, Ala‐329, has yielded many well preserved burials, approximately 300 of which are included in this study. The most common pathological lesions seen in this population are in the dentition. Advanced attrition is pervasive, affecting all individuals with teeth in occlusion for 2 years or more. Deciduous teeth are involved even in very young children and often show severe wear before replacement. In the permanent dentition, all elements are involved by the second decade; in the oldest age category (41 + years), all individuals show severe wear throughout their dentitions. In fact, by the end of the third decade, the majority of individuals have no enamel remaining. Mild periodontal involvement is found in 74% of adults, socket resorption in 53%, and abscesses in 31% of the relevant sample. Interestingly, although dental abscesses are found more than twice as often among males, socket resorption is seen more often among females. Dental caries are seen in only 10 individuals. The high incidence of peridontal remodeling, socket resorption, and dental abscesses is probably a secondary result of severe dental attrition. It is hypothesized that a large quantity of abrasives in the diet is responsible for the extreme degree of attrition, in fact, among the most severe for any population yet described.

“Something is always going wrong with our teeth. They don't last anything like a lifetime, usually. What chain of events in evolution should we thank for our mouthfuls of rotting crockery?” —Kurt Vonnegut, Galapagos, 1985.
Modeling the prehistoric Maori population
Authors: Brewis Alexandra A. , Molloy Maureen A. , Sutton Douglas G.
Published: August 2005

Skeletal and comparative evidence of mortality is combined with fertility estimates for the precontact Maori population of New Zealand to determine the implied rate of precontact population growth. This rate is found to be too low to populate New Zealand within the time constraints of its prehistoric sequence, the probable founding population size, and the probable population size at contact. Rates of growth necessary to populate New Zealand within the accepted time span are calculated. The differences between this minimum necessary rate and the skeletally derived rate are too large to result solely from inadequacies in the primary data. Four alternative explanations of this conundrum are proposed: 1) skeletal evidence of precontact mortality is highly inaccurate; 2) skeletal evidence of fertility is severely underestimating actual levels; 3) there was very rapid populatin growth in the earliest part of the sequence up to 1150 A.D., from which no skeletal evidence currently is available; or 4) the prehistoric sequence of New Zealand may have been longer than the generally accepted 1,000–1,200 years. These alternative are examined, and a combination of the last two is found to be the most probable. The implications of this model for New Zealand prehistory and Oceanic paleodemography are discussed.
Age variations in the relation of body mass indices to estimates of body fat and muscle mass
Authors: Micozzi Marc S. , Harris Tamara M.
Published: August 2005

In some chronic disease studies, distinctions have been made regarding the importance of body mass index (BMI) as a risk factor in younger versus older men and women. In order to determine the significance of these differences in BMI‐disease associations, we determined the extent of age‐dependent variations in the relation of BMIs to body composition in large probablity samples of U.S. men and women from the First and Second U.S. National Health and Nutrition Examination Surveys (NHANES I and II). BMIs are more highly correlated with estimates of body fat in younger than in older men and women, and with muscle mass in older than in younger adults. Caution should be exercised in interpreting the significance of BMI as a risk factor for chronic disease, particularly in comparison of age groups.
Partial humeri of two Miocene Colombian primates
Authors: Meldrum D. J. , Fleagle J. G. , Kay R. F.
Published: August 2005

Distal portions of humeri from two Miocene Colombian primates were recovered during field work in 1986. The larger IGM 183420 is very similar in size and morphology to the humerus included in the type specimen of Cebupithecia sarmientoi, recovered from La Venta in 1945 (Stirton and Savage: Serv. Geol. Nac. Bogata 7:345–356, 1951) and is assigned to this taxon. IGM 183420 presents a number of features of the humerus associated with clinging postural behaviors in living platyrrhines, including a medial epicondyle with very little dorsal angulation, a cylindrical trochlea, and a contact facet for the coronoid process of the ulna. In these and other features Cebupithecia most closely resembles the extant genus Pithecia.

IGM 183512 is approximately the size of Saimiri sciureus and is very similar in morphology to the humerus of this small arboreal quadruped. The medial epicondyle is more dorsally angled, the medial lip of the trochlea is more pronounced and the capitulum is less spherical as compared to Cebupithecia. This fossil is assigned to the taxon Neosaimiri fieldsi.
Effects of growth and speed on hindlimb joint angular displacement patterns in vervet monkeys (Cercopithecus aethiops)
Authors: Vilensky Joel A. , Gankiewicz Eva
Published: August 2005

Hip, knee, and ankle joint displacement patterns are compared across both age and speed for five immature vervet monkeys sampled approximately every 6 months over a 3 year period. The analysis indicated that, as a group, the animals displayed no consistent changes in joint patterns as they grew. However, individual animals showed consistent patterns. There were also no consistent effects of size across animals at the walk–gallop transition. This is contrary to McMahon's prediction (J. Appl. Physiol. 39:619–627, 1975) based upon his elastic‐similarity model of animal scaling. With increasing speed, when symmetrical gaits were used, all of the animals tended to show a decrease in the relative positions of the hip, knee, and ankle maximum values. Furthermore, across the walk–gallop transition, the animals tended to show a decrease in the range of ankle and knee movements.
Can paleopathology provide evidence for “compassion”?
Authors: Dettwyler K. A.
Published: August 2005

Paleopathological analyses of skeletal remains have provided significant information about diet and health in prehistoric populations. A number of individuals have been recovered whose remains show evidence of impairments that would have precluded “normal” functioning, resulting in a disability. The most famous example is Shanidar I; more recent discoveries include the Romito 2 dwarf from Italy and a boy with spina bifida from the Windover site in Florida. These finds have been interpreted by some writers as evidence for compassion and “moral decency” among the other members of the community, who would have had to support these nonproductive individuals. However, these interpretations are based on a number of implicit assumptions: about the number of nonproductive members normally present in any population, about the abilities of disabled individuals by other members of the group, and about the “moral rightness” of facilitating the survival of a disabled individual under all circumstances. These assumptions are not justified by the evidence from the archeological record or by reference to ethnographic analogy. A tendency to focus on physical traits as the sole measure of productive ability, images of Rousseau's “noble savage” transported to the past, and unexamined beliefs about the disabled in modern societies have influenced these archeological interpretations. We are not justified in drawing conclusions either about the quality of life for disabled individuals in the past or about the motives or attitudes of the rest of the community from skeletal evidence of physical impairment.
Does brain size variability provide evidence of multiple species in Homo habilis?
Authors: Miller Joseph A.
Published: August 2005

Endocranial volume (ECV) variability as measured by the coefficient of variation (CV) has been important in supporting the view that more than one species is represented in Homo habilis. Supporters of this view used a CV of 10 as a standard to determine that 1) the H. habilis CV of 12.7 indicates multiple species and 2) there is a low probability of H. habilis specimens KNM‐ER 1470 and KNM‐ER 1813 being members of the same taxon. This study examines published data for ECVs of fossil and extant hominoids to determine whether CV yields any information regarding species number in H. habilis. Results indicate that there is no empirical basis for using a CV of 10 as a standard to detect multiple species in H. habilis. Also, geography, time, sample choice, sex ratio, and measurement technique are complicating factors that must be considered when interpreting CVs for fossil samples. Additionally, the broad 95% statistical confidence limits (5.1–20.3) indicate that the CV estimate of 12.7 for H. habilis is not sufficiently reliable to allow biologically meaningful interpretation. However, if the CV for H. habilis is actually 12.7, it still falls within the range of variation for single species of modern hominoids. The evidence from ECV variability does not support the argument for multiple species in H. habilis.
Cranial capacity evolution in Homo erectus and early Homo sapiens
Authors: Leigh Steven R.
Published: August 2005

This paper investigates patterns of cranial capacity evolution in Homo erectus, early Homo sapiens, and in regional subsamples of H. erectus. Specifically, models explaining evolution of cranial capacity in these taxa are evaluated with statistical techniques developed for the analysis of time series data. Regression estimates of rates of evolution in cranial capacity are also obtained. A non‐parametric test for trend suggests that cranial capacity in both H. erectus and early H. sapiens may increase significantly through time. Cranial capacity in an Asian subsample of H. erectus (comprised of Chinese and Indonesian specimens) increases significantly through time. Other sub‐samples of H. erectus (African, Chinese, and Indonesian) do not appear to increase significantly through time. Regression results generally corroborate results of the test for trend. Spatial and temporal variation may characterize evolution of cranial capacity in H. erectus. Different patterns of cranial capacity evolution may distinguish H. erectus from early H. sapiens.
Cranial growth in the squirrel monkey (Saimiri sciureus): A quantitative analysis using three dimensional coordinate data
Authors: Corner Brian D. , Richtsmeier Joan T.
Published: August 2005

Improvements in data gathering technology have made it possible to quickly and accurately digitize large numbers of objects. The three dimensional coordinates of 44 homologous landmarks were obtained from a sample of 104 squirrel monkey (Saimiri sciureus) crania. After sorting by sex, the crania were assigned to one of four dental age groups. Two quantitative methods, Euclidean distance matrix analysis (EDMA) and finite element scaling analysis (FESA), were used to study craniofacial form change during growth within each sex. Form differences between the sexes at each developmental age were also examined.

Both sexes show a small amount of cranial growth overall; however, there are areas of substantial local growth. These areas include the anterior neurocranium and basicranium, the basioccipital, and the anterior palate. Sexual dimorphism in the craniofacial complex is minimal. The most dimorphic regions are the orbitonasal portion of the lower face, the cranial base, and the palate.
Positional behavior of Pan troglodytes in the Mahale Mountains and Gombe Stream National Parks, Tanzania
Authors: Hunt Kevin D.
Published: August 2005

The positional behavior of habituated adult chimpanzees and baboons was observed for 784 hr in a year‐long study. Comparisons between species were made to establish the distinctiveness of chimpanzee positional behavior and habitat use. Brachiation (sensu stricto, i.e., hand‐over‐hand suspensory locomotion) was observed in low frequencies among chimpanzees, and its significance for chimpanzee anatomy is judged slight. Although no significant differences were found between sympatric baboons and chimpanzees in the proportion of time spent in the terminal branches, or in the mean diameter of weight‐bearing strata, chimpanzees exhibited evidence of a terminal branch adaptation in that they, unlike baboons, used postures among smaller supporting strata different from those used among larger supports. Among chimpanzees, unimanual arm‐hanging was most common among the smallest strata and was associated with smaller mean and median support diameter than other postures. Unimanual arm‐hanging was the only common behavior among chimpanzees that usually involved complete abduction of the humerus. A number of behaviors often subsumed under the label “quadrumanous climbing” were distinguished in this study. Compared to baboons and other cercopithecoids, chimpanzees did not show increased frequencies of large‐stratum vertical climbing, and their vertical climbing did not involve significant humeral abduction. Arm‐hanging (i.e., unimanual suspension) and vertical climbing distinguish chimpanzee positional behavior from that of monkeys.
Effects of fronto‐occipital cranial reshaping on mandibular form
Authors: Cheverud James M. , Midkiff James E.
Published: August 2005

Cultural reshaping (artificial deformation or modification) of the neurocranial vault provides an artificially increased range of morphological variability within which the relationship between the growing neurocranium and face can be investigated. We analyze crania which have been fronto‐occipitally compressed to ascertain possible morphological effects on the mandible.

We collected measures of mandibular breadth, length, and height from 82 modified (N = 48) and unmodified (N = 34) crania from a Peruvian Ancon series. Angle classification was also scored in order to investigate whether or not occlusal relationships were affected by neurocranial reshaping. Only intercondylar distance (posterior mandibular breadth) exhibited significant differences between unmodified and modified groups, though this difference was relatively small compared with vault deformation. The modified crania had a higher frequency of normal occlusion (Class I) than the unmodified crania.

Increased intercondylar breadth in modified skulls is due to a cascade of effects which begin with a direct effect of the fronto‐occipital deforming device on neurocranial shape (increased neurocranial width). The increase in mandibular breadth may be a compensatory response to increased cranial base breadth and maintains articulation between the cranial base and mandible. The increased posterior breadth, coupled with a slight decrease in mandibular depth, may contribute to the change in occlusal relationships suggested for this sample.