Degenerative changes of the spine in people of the Okhotsk culture were investigated in adult human skeletal remains from 38 males and 34 females. These findings were then compared with those in materials obtained from the medieval Kamakura period and early-modern peasants on Kumejima, Ryukyu Islands. The three samples clearly showed different patterns. In the Okhotsk series, the cervical spine of each sex had most osteophytes on the vertebral body, while the Kumejima samples had the highest frequency on the lumbar vertebrae. In the Kamakura series, males were most affected on the lower thoracic vertebrae. Moreover, severe osteophytes on the body of the lumbar vertebrae were more frequently seen in the Okhotsk males. Degenerative changes of the articular process of the Okhotsk series were most frequently seen in the lumbar vertebrae and least frequently seen in the cervical vertebrae. This is well contrasted with a high frequency of degenerative changes of cervical apophyseal joint in early-modern Kumejima peasants. The Kamakura series of each sex had generally low frequencies. Severe degenerative changes of apophyseal joint dominantly affected the Okhotsk series. It is inferred that different dynamic loads caused a high frequency of degenerative changes in the corresponding articular parts. For example, because the Okhotsk culture developed a considerable maritime infrastructure, the lifestyle required for sea-mammal hunting and fishing seems to have particularly affected the incidence of severe degenerative changes of the lumbar vertebrae.
Modern inhabitants of the Okinawa islands have been supposed to represent a relatively close genealogical connection to the prehistoric Jomon and the indigenous Ainu, when compared with people living on Japan’s main island (Honshu). However, several previous studies have also clarified some morphological facial traits discernible between the early-modern Okinawans and the Jomon of Honshu. In the present study, to further evaluate the Jomon–Okinawan relationship, we compared facial forms between skeletal samples from the Okinawa islands and Honshu, both in the Jomon and early-modern periods. Results of the comparisons showed that the Okinawa Jomon tended to possess a flatter interorbital region than the Honshu Jomon, but most measurements did not significantly differ between the two Jomon groups. This confirms that people sharing both Jomon culture and fundamental facial features lived throughout almost the entire Japanese archipelago, including the Okinawa islands. Results also demonstrated that the early-modern Okinawans had a significantly lower and broader face with transversely broader and flatter interorbital region than the early-modern Honshu Japanese. Such facial characteristics of the early-modern Okinawans qualitatively matched those of the Okinawa Jomon. However, compared with the Okinawa Jomon, the early-modern Okinawans exhibited an absolutely taller/narrower face and a further flatter nasal root. This could stem in part from a certain amount of population flow from surrounding regions during historic periods, as suggested by many earlier studies. Nevertheless, the results obtained in this study indicate that, comparatively, modern Okinawan people have retained physical traits including facial forms of the Jomon who survived in the same southernmost islands of the Japanese archipelago. Geographical variations of modern Japanese phenotypes should also be accounted for partly by those of the ancestral Jomon characteristics that were manifested by the end of the Jomon period.
It has been suggested that the physical condition of a mother may affect her pattern of investment in her sons or daughters. In addition, when competition over local resources becomes intense, severe aggression among the philopatric sex leads to a higher mortality of the sex and a biased birth sex ratio toward the opposite sex in the low rank. Parental sex-biased investment has been studied in many animal species to test these hypotheses, but the results have been highly inconsistent. We examined maternal sex-biased investment in relation to dominance rank using data on infant growth, infant mortality, birth sex ratio, and delay of subsequent reproduction by rearing current offspring from a provisioned, free-ranging Japanese macaque (Macaca fuscata) troop at Takasakiyama, Japan. The results showed that there was no sex difference in infant body mass among offspring of high- and low-ranking females. Use of the logistic regression model to analyze infant mortality with several independent variables failed to show a statistically significant sex bias. Birth sex ratio did not differ significantly between high- and low-ranking females. Among high-ranking females, there was no significant difference in delivery rate in the next year between those that reared a son and those that reared a daughter. For low-ranking females, however, the delivery rate after rearing daughters was markedly lower than that after rearing sons. Thus, there was no evidence of statistically significant maternal male-biased investment. For low-ranking females, we found a delay in subsequent reproduction for mothers after rearing daughters and no sex difference in offspring mortality. These results suggest that the females increased their offspring’s chances of survival, irrespective of sex, by postponing their subsequent delivery.
We analyzed the morphological and molecular phylogenetic characteristics of Sus bone and tooth specimens excavated from the Noguni shell midden and the Noguni B shell midden (c. 7200–4400 uncal. BP), in Okinawa main island. They were compared with those of Sus remains from later sites on the Okinawa Islands (c. 4800–1400 uncal. BP) as well as modern Ryukyu wild boar (Sus scrofa riukiuanus). Based on the length and breadth of lower third molars, Sus specimens from the Noguni shell middens were distinctly smaller than those from modern Ryukyu wild boar. Lower third molars from the Noguni shell middens also show a different size range from those of other ancient sites in the Okinawa Islands. Some haplotypes from the Noguni B shell midden belong to a different cluster from modern Ryukyu wild boar based on the analysis of mitochondrial DNA D-loop region, although nucleotide sequences are fragmentary. The morphological and molecular phylogenetic analyses indicate that Sus from the Noguni shell middens included different populations from modern Ryukyu wild boar. We suggest two possible hypotheses: first, the Sus from the Noguni shell middens were introduced to Okinawa main island from elsewhere; second, prehistoric wild boar that inhabited the Ryukyu Islands had a larger morphological and genetic variability than modern Ryukyu wild boar.
To understand the complex process underlying the emergence and growth of inequality in a population and its impact on individuals’ subjective quality of life (QOL), the authors conducted fieldwork in 2001 and 2009 in a rural minority community in Hainan Island, China. The tourism industry, which developed in 2001, provided paid jobs for half of the adult men in 2009. Responses on the abbreviated version of the World Health Organization Quality of Life questionnaire (WHOQOL-BREF) indicated that subjective QOL, socioeconomic status, and dietary quality were significantly higher among the individuals with paid jobs. The present case study suggests that Chinese minority communities that have undergone significant economic growth have experienced the emergence and growth of inequality in job opportunities, which has stratified the subjective QOL, dietary quality, and socioeconomic status within the community. These findings suggest that the stages of ‘health transition’ differed among individuals in the community, and that analysis of inter-individual variation in a community may contribute to a better understanding of health in rural Chinese communities.
The recent application of microtomographic techniques to dental morphological studies has revealed an untapped source of biological information about extinct and extant human populations. In particular, this methodology has helped to characterize internal dental structures (enamel–dentine junction, pulp chamber, and radicular canals), maximizing the amount of information that can be extracted from a given specimen. In this study, we present a three-dimensional evaluation of the dental roots of the Sima del Elefante mandible, ATE9-1 (Atapuerca, Spain) by visual inspection, and by tomographic and microtomographic techniques. With 1.3 Myrs of age, this fossil represents the earliest hominin remains in Europe, and one of the very few human fossils for this period and region. Through this case study we aim to present a protocol for the description of the internal dental spaces, exemplify how the application of microtomographic techniques can significantly increase the amount of relevant and informative morphological features (even in the case of fragmentary/heavily worn teeth or teeth with hypercementosis), and explore some biological considerations about external and internal root morphology. There is neither a general nor straightforward correspondence between the external root morphology and the root canals. In cases where a high degree of hypercementosis is present, the external root anatomy can be highly confusing. Indeed the assessment of the internal root anatomy of ATE9-1 teeth has led us to the reclassification of the LC and the LP3 with respect to previous publications. The results of this study suggest that internal root anatomy could be used as a complementary source of biological information.
Identified osteological collections are important sources for pathological studies, especially when the causes of death of the individuals are known. However, the individual may have suffered from other disorders, not related to the death and thus absent from written record of death. The aims of this paper are to describe the pathological signs perceptible on a skeleton, and to consider the possible aetiologies beyond the recorded cause of death. Skeleton number 470 belongs to the Identified Skeletal Collection of the University of Coimbra, Portugal. This female died in 1933, and pulmonary tuberculosis was recorded as the cause of death. The skeleton was observed macroscopically by the naked eye and with the help of a magnifying (10×) lens. Radiographic techniques were also applied. This individual presents skeletal abnormalities that include rib and vertebral agenesis, kyphoscoliosis, coxa vara in the right femur, left femoral head detachment with bone resorption in the corresponding acetabulum, and bilateral bowing of the fibulae. The differential diagnosis includes chromosomal or congenital, infectious, endocrine and metabolic diseases, with residual rickets the most probable pathological condition affecting this woman during her youth. This study shows that either in identified or unidentified skeletal samples, careful observation and a differential diagnosis is crucial.
It has been generally thought that a tiny freshwater fish, medaka (Oryzias latipes), has expanded its habitat into the Japanese archipelago as wet-rice cultivation spread across the region, and hence the distribution of medaka should be a matter of anthropological interest. However, there has been no study to verify this popular belief. To address the issue, we sampled wild medaka, and undertook genetic analyses of its populations. We collected 976 individual medaka from 13 local wild sites, which included 11 paddy-field irrigation channels and two ponds. The gene tree constructed based on nucleotide sequences of mitochondrial genome D-loop region showed no discrepancy in the topology, which is presumed to reflect the northern Kyushu origin of the southern Japanese medaka. Population genetic statistics indicated that the medaka populations in west Japan have greater genetic diversity (heterozygosity) than those in east Japan, supporting the hypothesis that the medaka originate from northern Kyushu. Hence, we argue that the current medaka distribution can be attributed to their past migration event(s) following the expansion of paddy fields from northern Kyushu to the eastern part of the Japanese archipelago.
Anthropological Science, 119 (3): 265–271. REFERENCES The following literature lacked in the list. Ishii M. (1976) Cold tolerance of Japanese assessed by the lower critical temperature and so on. The Journal of Anthropological Society of Nippon, 84: 93–104 (in Japanese with English abstract).