Three excavations in the 1950s of the Zaimokuza site in Kamakura, Japan, uncovered human skeletal remains, mainly crania, of a large number of individuals buried in mass graves. Materials from the first and second excavations were previously reported as being victims of Nitta Yoshisada’s siege of Kamakura (1333) in part due to the high incidence of weapon-related trauma. Recent archaeological excavations in the area near the site have shown that it lies within a large contemporary medieval graveyard and despite consistencies in burial conditions, evidence for violent trauma, while present, was found in much lower frequencies in surrounding sites. Many of the traumas reported in the original study on the Zaimokuza skeletal remains were ‘scratches,’ described as extremely short and shallow cut marks on the crania, and it had been suggested that taphonomically induced bone surface modifications may have been mistakenly recognized as human-induced traumas. This study uses scanning electron microscopy to re-examine the Zaimokuza materials for ‘scratches’ and investigates their causes. A total of 235 examples of marks matching the description of ‘scratches’ were found on 38.2% of individuals examined that varied in their morphologies and were likely caused by different agents for different reasons. The results indicate that most were groups of ‘weak and shallow’ marks that display microscopically identifiable features commonly found on marks caused by sedimentary abrasion described in recent taphonomic studies, and so were likely caused by natural processes before burial. In addition, we found marks similar to ‘scratches’ inflicted post-excavation on clay used to restore a specimen. When taking the results into consideration, some of the interments at the Zaimokuza site may represent burial customs of the medieval period such as ‘corpse abandonment,’ rather than casualties of warfare and violence.

Developmental variations in the cranial vault arise during early ontogenesis due to premature or delayed suture closure, non-union between the normal ossification centers, and emergence of additional ossification centers. These variations cause abnormal calvarial partition and are often associated with modifications of the overall cranial configuration. This study aims to evaluate the impact of metopic suture persistence and the development of supernumerary bones in the occipital region on neurocranial morphology. A series of 245 crania of Bulgarian males was investigated. According to the presence or absence of developmental variations in the frontal and occipital bone they were divided into four series: control (n = 115); crania with a retained metopic suture (n = 32); crania with supernumerary bones in the occipital region (n = 67); and metopic crania with supernumerary bones in the occipital region (n = 31). Polygonal 3D models were generated, on which the 3D coordinates of 35 landmarks describing the neurocranium were collected. Geometric morphometric analyses were applied to compare the size and shape of the landmark configurations. Significant size differences were observed only in the frontal and occipital bone configurations between the metopic crania with occipital supernumerary bones and the non-metopic crania. Significant shape differences were found in all comparisons between the metopic and non-metopic groups for all configurations, except the occipital one. Metopism has a significant impact on overall neurocranial morphology, which is intensified by the presence of supernumerary bones in the occipital region.

To evaluate burial customs in the Jomon period of Japan, we observed the taphonomic signatures of human bones from a secondary collective burial and compared them with those from individual burials. We compared the compositions of identified bone parts, degree of weathering, and damage of the bone surfaces based on two neighboring shell-mound sites, Gongenbara and Horinouchi in Chiba Prefecture; a famous secondary collective burial had previously been discovered at the Gongenbara shell-mound. The degree of weathering differed between the collective and individual burials, and also differed depending on the horizontal and vertical location within the collective burial. These differences imply that a variable degree of weathering plausibly occurred at or after the secondary burial, but not at the primary burial. Regarding bone surface damage, specific types of damage were more frequently observed on the limb bones in the collective burial than in the individual burials, although different types of damage were observed in the skull assemblage. These findings suggest that different burial processes could cause the secondarily reburied bones to be exposed to the air for a longer duration of time or more easily be accessed by insects or other small animals, which might have produced variable taphonomic signatures.

The dental tissue proportions of human permanent canines are one of only a few sexually dimorphic features that are present in childhood, and therefore offer the opportunity to estimate the sex of immature individuals. This work aims to evaluate for the first time the degree of sexual dimorphism in the three-dimensional (3D) measurements of deciduous canine dental tissues, to assess their potential in sexual assessment. Computed microtomographic techniques have been employed to analyse the maxillary and mandibular deciduous canines of 65 individuals (36 females and 29 males) of known sex and age. The teeth were scanned and the volumes and 3D surface areas of the enamel cup and the dentine–pulp complex were obtained. Our results did not show statistically significant differences in either the absolute or relative dimensions of the enamel and dentine between female and male teeth. We hence conclude that volumes and 3D surface areas of deciduous canine dental tissues do not allow for sex determination, which contrasts with what has been observed in permanent canines by other authors. The differences in the degree of sexual dimorphism in dental tissue proportions between permanent and deciduous canines seem to be due to a decrease in the intersexual variability of the dentine component dimensions. Since the dentine component is a tissue capable of responding to changes in sex hormone concentration levels, our results might indicate that hormones play a more important role in the development of sexual dimorphism in the permanent dentition than previously thought.

Adult individuals from the Jomon period are known to have upper- and lower-limb skeletons characterized by relatively longer distal segments (radius and tibia) than their proximal counterparts (humerus and femur, respectively), in contrast to later historical and modern Japanese individuals. However, it is currently unclear at what age the characteristics of Jomon limb segment proportions emerged and reached adult-equivalent levels. To address these issues, we compared representative intersegmental ratios of limb bone length (e.g. brachial index, crural index, and intermembral index) between Jomon and four other Japanese groups from fetal life to adolescence, and described the limb proportions and growth patterns characteristic of Jomon at different stages of growth. The specimens included humeri, radii, femora, and tibiae from 143 prehistoric Jomon, 22 protohistoric Yayoi, 79 medieval Kamakura-Muromachi, 76 early modern Edo, and 311 modern Japanese skeletons, ranging in estimated age from the fifth fetal month to 19 years. The results confirmed that fetal Jomon individuals had relatively longer distal segments than their proximal counterparts in both the upper- and lower-limb skeletons compared with modern Japanese individuals, and that the Jomon maintained their comparatively long forearm and lower leg bones from childhood through adolescence. Furthermore, for all chronological groups, including the Jomon, the respective distal/proximal ratios of the upper- and lower-limb skeletons reached adult equivalence at approximately 1.5 years of age and remained nearly constant throughout subsequent growth. These findings suggest that the elongated forearm and lower leg bones of the Jomon may be derived primarily from the morphogenetic pattern of the limb cartilage primordium during early development, and that group-specific limb proportion characteristics may be established by the first two years of life at the latest.

The life of the long-established Russian inhabitants of Western Siberia has been well described. In fact, archaeological, ethnographic, and other information on its various aspects is abundant. Archaeoparasitological data, on the other hand, is lacking, particularly with regard to parasitosis incidence. In the present study, eggs of such fish parasites as Opisthorchis felineus and Diphyllobothrium spp. were identified in soil samples taken from the sacral surface of bodies that had been buried in the Gornopravdinskiy burial ground (on the Lower Irtysh River) in the 18th or 19th centuries. The study findings indicate that fish was a key component of the diet of the rural Russian population of that area. No statistically significant sex differences in fish consumption were identified. The parasitological spectrum of the population under consideration was narrow relative to the diversity of parasitoses in urban Russian populations. This fact probably reflects the lower-intensity population flows, their limited radii, and the different economic activities pursued by those people. Based on the archaeoparasitological data, the latter seem to have been closer to the economic activities practiced by the indigenous populations of Western Siberia.