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Hokkaido is an intriguing region for studies of population history in Japan because of its geographical position both at the periphery in the Japanese archipelago and at the gateway to the northeastern Eurasian continent. This paper focuses on the biological relationship between two populations, Okhotsk culture people and Ainu, and investigates cra...
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Citations
... The cultural heritage of indigenous people (e.g., Nahuas living in Mexico and El Salvador, Ainu living in the northern hemisphere of the world, Assyrians living in Western Asia, and the like) is full of aesthetic patterns, which can also be studied using the concept of symmetry. The focus of this article is the patterns of the indigenous people living in the northern part of Japan, known as Ainu [5,6]. Ainu people decorate their houses, clothing, ornaments, utensils, and spiritual goods using some unique patterns [7][8][9][10][11][12]. ...
This article addresses virtual and physical prototyping of some symmetrical patterns collected from the Ainu cultural heritage. The indigenous people living in the northern part of Japan (e.g., Hokkaido), known as Ainu, often decorate their houses, clothing, ornaments, utensils, and spiritual goods using some unique patterns. The patterns carry their identity as well as their sense of aesthetics. Nowadays, different kinds of souvenirs and cultural artifacts crafted with Ainu patterns are cherished by many individuals in Japan and abroad. Thus, the Ainu patterns carry both cultural and commercial significance. A great deal of craftsmanship is needed to produce the Ainu patterns precisely. There is a lack of human resources having such craftsmanship. It will remain the same in the foreseeable future. Thus, there is a pressing need to preserve such craftsmanship. Digital manufacturing technology can be used to preserve the Ainu pattern-making craftsmanship. From this perspective, this article presents a methodology to create both virtual and physical prototypes of Ainu patterns using digital manufacturing technology. In particular, a point cloud-based approach was adopted to model the patterns. A point cloud representing a pattern was then used to create a virtual prototype of the pattern in the form of a solid CAD model. The triangulation data of each solid CAD model were then used to run a 3D printer to produce a physical prototype (replica of the pattern). The virtual and physical prototypes of both basic (Hokkaido) Ainu motifs and some synthesized patterns were reproduced using the presented methodology. The findings of this study will help those who want to digitize the craftsmanship of culturally significant artifacts without using a 3D scanner or image processing.
... Landmark-based studies of cranial samples from the Japanese archipelago have recently increased in popularity (e.g. Makishima and Ogihara, 2009;Fukumoto and Kondo, 2010;Fukase et al., 2012). Compared to the conventional osteometric method used for evaluating alveolar prognathism, landmark-based 3D morphometry can visualize variations in the alveolar region in relation to the whole facial architecture more effectively. ...
Prognathism in the human facial skeleton is generally divided into two types: alveolar and facial. The degree of alveolar prognathism has conventionally been evaluated using the alveolar profile angle, defined on the basis of the line through the nasospinale and prosthion and the Frankfort horizontal (FH). Previous examinations of Japanese crania from the protohistoric Kofun period (c. 300–700 AD) to the modern period have established that the medieval (c. 1200–1600 AD) Japanese possessed the strongest alveolar prognathism. However, the nasospinale is an ambiguous landmark that is difficult to determine. Moreover, it has been suggested that the alveolar profile angle itself is problematic for quantifying alveolar prognathism. Here, we devised a new method for evaluating each type of prognathism independently and investigated temporal changes in the Japanese population using three-dimensional (3D) coordinate landmark data collected with a 3D contact digitizer. Facial prognathism was quantified using an obtuse angle, termed the midfacial protrusion angle, created by a line that runs through the nasion and subspinale with the FH. Alveolar prognathism was evaluated using a reflex angle, named the alveolar protrusion angle, formed between the nasion–subspinale and subspinale–prosthion lines. An analysis of 66 male crania derived from the northern Kyushu and Yamaguchi (westernmost part of Honshu) region showed no significant change of the alveolar protrusion angle over time from the Kofun period to the modern period. In contrast, the midfacial protrusion angle increased from the Kofun period to the medieval period and then decreased in the modern period. These results suggest that the strongest facial prognathism was exhibited in the medieval period. Previous results, which suggested that alveolar prognathism was strong in the medieval Japanese, may have been significantly affected by facial prognathism.
... Regarding sexing, we referred to collection records, while double checking the validity by observing hipbone morphology. The Okhotsk sample consists of northern and eastern subsamples with little craniometric difference (Fukumoto and Kondo, 2010), dated between c. 400 and 1200 AD (Komesu et al., 2008;Tsutaya et al., 2014Tsutaya et al., , 2015. The early-modern Honshu materials derive from anatomical collections made by the University of Tokyo around 1900 AD. ...
Objectives
Geographic variation in human nasal form has often been interpreted as a climatic adaptation, owing to the nasal air-conditioning function. The aim of this study was to further address morphofunctional issues of the nasal cavity, using three human groups from subarctic, temperate, and subtropical regions of the Japanese Archipelago: prehistoric Okhotsk, early-modern Honshu and Okinawa groups.Methods
Using three-dimensional coordinates of craniometric landmarks surrounding the nasal cavity, we compared linear measurements regarding nasal cavity form among the three groups and also conducted 3D geometric morphometrics.ResultsBoth linear measurements and morphometric analyses corroborate the previously reported covariation pattern of nasal cavity shape with climate, where humans from a cold/dry climate tend to possess a relatively tall, narrow, and deep nasal cavity compared with those from a warm/humid environment. The northern Okhotsk group had overall larger cranial airways, which may be attributable to their large facial skeleton. However, the ratio of nasal/bimaxillary breadth was significantly lower in the Okhotsk group, indicating that maxillary size does not necessarily constrain the nasal breadth. In addition, despite the presence of obvious geographic clines in anterior nasal shape, posterior choanal shape lacked the north-south geographic cline. This suggests a certain level of morphofunctional independence between the anterior and posterior nasal openings.Conclusions
The observed geographic variations must, however, be partly considered as a reflection of different ancestral traits and population histories of the three groups. Nevertheless, the results indicate that intergroup variations in nasal cavity morphology can be largely explained by climatic conditions. Am. J. Hum. Biol., 2015. © 2015 Wiley Periodicals, Inc.
... However, the timing, extent, and nature of admixture are regionally and temporally complex and the subject of continued study (e.g. Suzuki et al., 2004;Nakahashi and Iizuka, 2008;Adachi et al., 2009;Hanihara and Ishida, 2009;Ishida et al., 2009;Kawakubo et al., 2009;Matsumura and Dodo, 2009;Sato et al., 2009;Fukumoto and Kondo, 2010;Kaburagi et al., 2010). ...
Although dental size and morphology have contributed to population history studies in Japan, little attention has been paid to root size and dimensions. We report here computer tomography (CT)-based metrics of mandibular tooth roots in modern Japanese, Holocene Jomon, and Late Pleistocene Minatogawa human fossils (15000-20000 BP). Our results confirmed that, in terms of both mesiodistal cervical diameters and root lengths, the Jomon is overall smaller-toothed, with summed mesiodistal cervical diameters 4% smaller than in the modern Japanese. However, no significant differences were found in the M-1, in both cervical diameter and root length. These results are comparable to the crown size differences reported in the two populations. There were no significant differences in root proportions (root length relative to cervical diameter) between the Jomon and the modern Japanese in each tooth element from I-1 to M-1, while an allometric root length reduction was observed in the M-2 and M-3 of the modern Japanese. This reflects distinct patterns of dental reduction in the two populations. The Late Pleistocene Minatogawa fossils were found to have larger cervical diameters and root lengths than either the modern Japanese or the Jomon, in some respects approximating the large-toothed Australian and/or earlier Late Pleistocene Homo sapiens conditions. This indicates a largely conservative dental system retained in the Minatogawa fossils, distinct from the Jomon condition.
Combined with archival and osteological researches and radiocarbon dating, this study reports the provenance and chronology of the human skeletal remains of about 40 individuals derived from 11 Jomon or Epi-Jomon prehistoric sites in South and Central Hokkaido. They were found by 1960s and once deposited in Department of Anatomy, Hokkaido University School of Medicine. Update of information on age and sex for each individual is also a part of the present study. It confirmed that these skeletal remains were probably younger than previously documented. Although ¹⁴C date of human remains in this region show the marine reservoir effects through the marine resource consumption, a complicated oceanography around Hokkaido makes it difficult to estimate local reservoir ages (ΔR). Hence, we calculated two corrected ages for each specimen using local ΔR and another larger ΔR values, the latter of which was originated from East Sakhalin Current area from where seasonally migrated sea mammals travelled. The ranges of thus corrected ¹⁴C dates for the human remains were roughly consistent with but tended to be younger than those expected from the archaeological contexts or pottery chronology. Correction method for marine reservoir effects in human remains and pottery residues needs to be further discussed.
