Development of the preauricular groove has long been used as an osteological indicator of pregnancy and childbirth despite inconsistent evidence. To retrospectively evaluate the development of preauricular groove, we measured the preauricular groove volume based on pelvic computed tomography (CT) images before and after childbirth and examined its relationship to obstetric history including gravidity, parity, and the number of miscarriages. Longitudinal CT data were obtained from three females before and after childbirth, and cross-sectional CT data were collected from 98 females (47 nulliparous and 51 parous). One case of forceps delivery showed marked enlargement of the groove after childbirth in both sides, whereas no notable changes were observed in a case of cesarean section. Another case of vaginal delivery exhibited enlargement on one side and no change on the other. Cross-sectional comparisons showed that the volumes of preauricular groove were significantly larger in parous than in nulliparous females although there was a substantial overlap. No significant correlation was found with parity or gravidity, although a weak negative correlation was suggested with the number of miscarriages. The volume showed no significant association with age, height, or weight. These findings indicate that the preauricular groove may develop after first parturition but does not reliably reflect parity or gravidity. It was also suggested that factors contributing to recurrent miscarriage may negatively affect preauricular groove development.

Food systems is an analytical framework developed in agricultural economics that encompasses the entire process from food production, processing, distribution, preparation, to consumption. In archaeology, the distinction between food supply, which indicates the presence of food resources within a region, and accessibility, which reflects the extent to which individuals could actually obtain these resources, potentially enables a more nuanced reconstruction of past human diets. In this study, we utilized this food system framework to investigate the accessibility of food items for commoners in premodern Osaka, a logistical hub with a diverse food supply. Carbon and nitrogen stable isotope analysis of bone collagen and palaeoproteomic analysis of dental calculus were performed for eight skeletal individuals from the Ofuka-cho site. The stable isotope ratios were within the previously reported ranges for premodern commoners in Japan. A total of 38 dietary proteins across 17 taxa were identified in the calculus. The identified food items included Pagrus major, which was an economically high-grade fish, Salmonidae, which was traded over long distances, the meat of terrestrial mammals, which were publicly avoided during this period, and cottonseed, which was possibly used as an edible oil. These findings reflect high accessibility to diverse food items even among commoners, which was maintained by the well-developed transport network of premodern Osaka. These results emphasize the pivotal role of commoners in the development of Japan’s culinary culture.

The first human skeleton (DHS-1) excavated in 1953 at the Doigahama site (Yayoi period, Shimonoseki City, Yamaguchi) is commonly known as the ‘u wo daku onna’ (‘woman embracing a cormorant’). This name originates from the identification of avian bones found near the breast of this middle-aged female as a chick of the Japanese cormorant (Phalacrocorax capillatus). However, a recent morphological re-examination of these avian bones clarified that they were not those of a juvenile cormorant. Additionally, three of the avian bones were found to have been bitten by small animals, which raises questions about the premise that these bones were buried at the same time as DHS-1. In this study, we observed and compared the surface morphology of DHS-1 and the associated bones (infant human bones (DHS-1a) and avian bones), and re-examined the possibility of simultaneous burial of these remains from taphonomic perspectives. We observed three types of damage (types A, B, and C) in the bones. Of these, two types of damage (types A and B) were observed in DHS-1. The characteristics of type A were consistent with those reported as traces of insect bites, and type B with those reported to be derived from plant roots. Type C, presumed to be animal bite marks such as those from small carnivores, was found only in the avian bones and DHS-1a, but not in DHS-1. Considering the appearance patterns of the damage, we hypothesize that after the burial of DHS-1, the sand moved and the body was temporarily exposed. When it was covered with sand again, the avian bones and DHS-1a were buried near DHS-1. Subsequently, all these bones were then excavated together.

The positions of the rostral opening of the pterygoid canal and the foramen of the zygomatic nerve in dogs and wolves were observed using samples taken from the crania of 144 contemporary Japanese dogs, 45 European dogs, and 36 grey wolves. The rostral opening of the pterygoid canal was located in the pterygopalatine fossa in 85–100% of the European dog and grey wolf individuals examined in this study; however, in 35% of the Japanese dogs, the opening was found in the medial wall of the orbital fissure, at a relatively high incidence rate compared with European dogs and wolves. This trait of the Japanese dogs is considered to be a variant, and to learn about its origin the crania of 45 Jomon dogs (5th millennium–10th century BC), 1 Jomon Japanese wolf (c. 6000 BP¹⁴C), 13 Yayoi dogs (5th–4thcenturies BC), 14 dogs from China (5th millennium–20th century BC), and 108 dogs from Susuya site, Sakhalin (4th century BC–6th century AD) were examined. The rostral opening of the pterygoid canal in the orbital fissure of the Neolithic period dogs from Japan and China had an occurrence rate of 73–100%, higher than that of contemporary Japanese dogs, giving rise to the possibility that this variant of the contemporary Japanese dogs is an inherited trait. It should be noted that in the modern 8 Japanese wolves (c. 17th century AD), 75% were of the orbital fissure type, and the Jomon Japanese wolf also had a pterygoid canal which opened into the orbital fissure, a trend differing from that of the grey wolf elsewhere in the world. The foramen for the zygomatic nerve was present in Jomon dogs at a relatively high occurrence rate. However, it was rarely observed overall among the dog specimens examined, and none were observed in the wolf samples.