We present a new approach called computational shape analysis, which utilizes a Fourier-wavelet representation for characterizing shape features of 2-D forms commonly encountered in a wide set of sub-disciplines within the biological sciences. The morphology of interest consists of the human cranial base (CB) as depicted on lateral cephalometric radiographs. Given a complex irregularly bounded form in Cartesian coordinate space, we first compute elliptical Fourier functions (EFFs) using a set of closely-spaced pseudo-homologous (x, y) points, starting at basion, to create a precise analog of the closed contour. This computed contour is then scaled (size-standardization) and rotated (positional-orientation) to provide for a common normalization. This insures that the representation is invariant with respect to starting point, size and orientation. Utilizing the EFFs, global aspects of the CB can then be extracted. The coordinates derived from the EFF were subsequently submitted to a continuous wavelet transform (CWT). Wavelet coefficients were then computed to identify localized features. The significant advantage of wavelets is that they are able to objectively identify changes in boundary curvature, thereby depicting localized aspects not easily attainable with other methods. Utilizing a sample of 297 Japanese cranial base outlines, statistically-significant differences in sex and archeological age were found. Although archeological age differences were present, they were small and largely random in character, suggesting stability in the CB structures. The presence of sexually dimorphic differences is consistent with earlier data derived from studies of Macaca nemestrina. In the current study, these differences in sexual dimorphism were present for every group starting with the Yayoi period and continuing up to the Modern period. Consequently, one may infer that the pattern of sexual dimorphism documented in the Japanese CB, is a primate pattern with an ancient evolutionary history. Wavelets were particularly useful in objectively identifying this sexual dimorphism. The results demonstrate that the Fourier-wavelet representation is a practical approach for numerically describing and visually depicting both global and localized features.

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Globally there was a reduction in the size and robusticity of the human orofacial skeleton and dentition after the Pleistocene. There was also diachronic change in brain size and skeletal mass in general. Anthropologists have developed numerous models in explanation of the evolutionary process, with the majority linked to the cultural developments of the Neolithic. These cultural models are challenged by the skeletal evidence from societies with contrasting culture histories. In China there is a reduction in facial breadth, height and prognathism, posterior tooth size, brain volume and cranial robusticity from the Neolithic to the modern period. However, the height of the orbits increases rather than decreases. Examination of the structural relationships between orbit and facial dimensions in Tohoku Japanese and Australian Aboriginal crania suggests a steady reduction in orbit volume in China. This may have resulted in a more anterior placement of the eyeball and associated structures in modern East Asians than in their Neolithic counterparts.

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The purpose of the present study was to assess evidence of secular changes in cephalic measurements and to clarify the causes of brachycephalization. Somatometric data of the head and face were investigated for secular changes by comparing data measured by the same observer for 2 groups of subjects differing in age by 45 to 50 years, and by examining trends of the last 100 years. Relationships between measurement, birth year, age at measurement, and year at measurement were examined using partial correlation coefficients. A positive secular change was observed for head breadth, which had a pattern of change that was very similar to that of height. Head length first decreased and then increased. No trend was observed for bizygomatic breadth when the year of measurement was considered. It appears that thickness of the soft tissue on the face is significantly influenced by nutritional status at the time of measurement. Measurement errors in total head height were apparently too large for analysis of secular changes. The parallelism between head breadth and height suggests that nutritional improvement in prenatal and early postnatal life is a plausible cause of the brachycephalization in the last 100 years. The finding that face measurements do not show clear secular change may indicate that they are more strictly determined by function than is the case for measurements of the neurocranium. As possible causes for the difference in secular change in head form/dimensions between Asian and European populations, differences in timing and dominant direction of the very rapid growth of the brain are discussed. There is inconsistency between the pattern of secular change in the 20th century and that of the 14th to 19th centuries. The possible causes of this are also discussed.

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JC virus (JCV) genotyping is a novel method of tracing human migrations. In the present study, we used this method to gain insights into human expansions to the western Pacific. Using the whole genome approach, four genotypes of JCV (8A, 8B, 2E, and 7A) were previously detected in the island populations of the western Pacific. Using the same approach, we detected five genotypes (B1-a, B3-a, B3-b, SC-f, and SC-x) in Filipino populations (B3-b and SC-f corresponded to 2E and 7A, respectively). From these findings, it was concluded that seven genotypes of JCV were spread in the island populations in Southeast Asia and the western Pacific (these genotypes were tentatively designated as the ocean genotypes). Three of them (B1-a, B3-a, and SC-f/7A) occurred in the Philippines but did not occur in the western Pacific; two (B3-b/2E and SC-x) occurred in the Philippines as well as in the western Pacific excluding Guam; and two (8A and 8B) occurred only in the western Pacific. These regional distribution patterns for the oceanic genotypes suggested various human migrations to the Pacific, some restricted to islands near the Asian Continent and some extended far to Remote Oceania. Furthermore, our findings were consistent with the view that the Austronesians originated in an area of Southeast Asia, including the Philippines.

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The longitudinal growth of individual stature of the Tokyo Metropolitan University growth study was characterized from early childhood to adulthood. The samples used here were 483 males and 262 females. The well known double phasic growth (JPA-2) and triphasic generalized logistic (BTT) models were used through the software AUXAL 2.01 for characterizing individual growth of stature. Growth parameters were extracted from the estimated distance and velocity curves for each individual. Predicted growth parameters including predicted adult stature were selected for the development of further prediction. Six prediction equations of adult stature on growth parameters (an improvement of Ali-Ohtsuki equations) have been established for Japanese boys and girls. The preciseness of the predicted equations in the present study was found to be sufficiently greater than preciseness of the existing predicted equations.

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Relative abundance and body size were compared among six primate genera found from the Pondaung Formation (latest middle Eocene, Myanmar). Pondaungia, consisting of two species, is the most common primate in the Pondaung fauna. A high abundance of Pondaungia savagei, the larger species, is recorded at the northern fossil localities (Mogaung area). At the southwestern localities (Bahin area), the primates are taxonomically more diverse than in the other areas, and there are no significant differences in abundance of the amphipithecid genera, Myanmarpithecus, Amphipithecus, and Pondaungia. The body sizes of the three eosimiid taxa (Eosimias-like eosimiid, undescribed eosimiid, and Bahinia) and Myanmarpithecus are distinct from one another, but those of the Amphipithecus and Pondaungia species are inseparable. The postcranial bones of a large-sized primate (NMMP 20) from the Pondaung Formation, consisting of humeral, calcaneal, ulnar, and vertebral fragments, most likely belong to Pondaungia cotteri or Amphipithecus mogaungensis, based on comparisons of body mass estimates of NMMP 20 with those of the taxonomically allocated dentognathic specimens. Although NMMP 20 was previously cited as Pondaungia savagei, we consider the current evidence to be insufficient to resolve its species or generic-level taxonomic assignment.

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Sexual diagnosis of skeletons is of importance to physical and forensic anthropologists. The present study attempts to provide a basis from which one might choose a variable of a long bone that is most suitable in sexual assessments of skeletal material. A total of 47 variables of the humerus, radius, ulna, femur, and tibia of 64 recent-modern Japanese (32 male, 32 female) were investigated. The data were analyzed using the t-test and the stepwise discriminant analysis. The width of the articular surface of the distal humerus, the sagittal head diameter of the radius, the diaphyseal cross-section area or the articular breadth of the ulna, the bicondylar width or the transverse diameter of the lateral condyle of the femur, and the proximal epiphyseal breadth of the tibia were useful in sexual diagnosis of each of the long bones. Total accuracies of sex determination using these variables ranged from 91 to 95%. Among these measurements, sexual dimorphism tended to be greatest in the breadth diameters of the elbow and knee joints.

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The morphological features of the first human parietal fossil found at the Shuidonggou site of Ningxia, China are described and compared with other specimens. Our results show that most of the features of the Shuidonggou parietal resemble those of modern humans. On the other hand, this specimen was found in situ adjacent to the erosional surface of the late Pleistocene stratum and exhibits a certain degree of fossilization. There are two features which are different from modern humans and similar to those of fossil hominids. One of the features is the strong ridges between the striae parietalis suggesting that the temporalis muscles were more developed than in modern humans. The second feature is the lack of a sigmoid sulcus at the mastoid angle of the Shuidonggou parietal which is similar to the situation seen in Homo erectus of Zhoukoudian. Given the similarities of many morphological features between late Pleistocene and modern humans, it is impossible to set the age or evolutionary status of the fossil accurately just from skeletal morphology of a fragmentary parietal. Nevertheless, taking the specimen’s fossilization and the background information of the site into consideration, we believe that the parietal likely comes from the late Pleistocene human populations that lived in this area.

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We studied an Egyptian mummy housed in the Otago Museum, Dunedin, New Zealand. Radiocarbon dating indicates that the age of the mummy is 2,358 BP, which is the period of the 30th Dynasty of Nakhthorhebe. Serial CT scans show that the heart had been removed, which is unusual among Egyptian mummies. In contrast, the brain had been left in situ. The orbital breadth suggests a degree of hypertelorism, being at the upper limit of the values recorded for ancient Egyptian males. There is extensive dental disease with excessive tooth wear and tooth loss, typical of Egyptian mummies. The wrapping material, examined under SEM, is probably a linen textile with a selvage.

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