Reconstruction of the life history and population history of the Okhotsk people based on the analysis of human skeletal remains

研究鄂霍次克人及其邻近民族的非测量颅骨变异。鄂霍次克岩系的横骨缝遗迹的发生率是现存种群中最高的。用Konigsberg方法（1990）对22个非度量性状进行了生物距离的估计。相邻连接方法（Saiton和Nei，1987）被应用于距离矩阵以生成无根树。北海道阿伊努人和绳文人被聚集在一起，与鄂霍次克阿伊努人和萨哈林阿伊努人组成一个集群。该集群还加入了新石器时代的贝卡特，阿穆尔，弥生和现代日本。另外三个不同的分支从中心出现;第一个包括马里亚纳群岛和夏威夷，一个分支，这是最接近亚洲，特别是东南亚岛民;第二个分支的高潮是俄罗斯，塔加尔和哈萨克;第三个分支包括一个孤立的北极分支。为了研究儿童早期的营养障碍或疾病，对来自北海道的人类骨骼遗骸的牙釉质发育不全进行了调查。绳纹人和阿伊努人样本的釉质发育不全的频率很高，影响超过70%的个体，而Epi-Jomon和鄂霍次克人的釉质发育不全的频率相对较低（56-57%）。然而，这一差异在统计上并不显著，可能是因为样本量小。牙釉质破裂的高峰年龄似乎是4-5岁。根据对阿伊努人个体样本的统计分析，没有观察到牙釉质发育不全形成与龋齿易感性之间的显著相关性。

Nonmetric cranial variation of the Okhotsk and their neighboring peoples was investigated. The incidence of the transverse zygomatic suture vestige in the Okhotsk series is the highest among living populations. Estimates of biological distances were carried out with Konigsberg's method (1990) using 22 nonmetric traits. The neighbor-joining method (Saiton and Nei, 1987) was applied to the distance matrix to generate an unrooted tree. The Hokkaido Ainu and Jomon are grouped together and join a cluster with the Okhotsk and Sakhalin Ainu. That cluster also join with the Neolithic Baikat, Amur, Yayoi and modern Japanese. Another three distinct branches emerge from the center ; the first consists of the Marianas and Hawaii, a branch which is closest to the Asian and especially Southeast Asian Islanders ; a second branch culminates in Russian, Tagar and Kazakh ; a third includes an isolated arctic branch.Dental enamel hypoplasia of the human skeletal remains from Hokkaido was investigated in order to examine nutritional disturbance or diseases during early childhood. The frequency of enamel hypoplasia of the Jomon and Ainu sample is high, affecting more than 70 % of the individuals, while that of the Epi-Jomon and Okhotsk is relatively low (56-57%). That difference is, however, not statistically significant, probably because of their small sample size. The peak age for enamel disruption seems to be 4-5 years. No significant correlation between the dental enamel hypoplasia formation and the susceptibility to dental caries is observed on the basis of statistical analysis of the Ainu individual sample.