Половой диморфизм размеров тела в раннем и первом детстве и «качество» среды: уровень антропогенной нагрузки и степень экстремальности климата места жительства

Abstract

Sexual somatic dimorphism through early and first childhood and «quality» of environment (the level of anthropogenic stress and climatic extremeness of the residence place) Introduction. The goal of study – quantitative conformities of intergroup variability of the level of sexual dimorphism (SD) of somatic traits of children of early and first childhood in connection with ecological factors – the degree of urbanization and the geographic latitude of the residence place of population. Material and methods. The analysis embraces the wide specter of ethno-territorial samples of 3-year-old and 6-year-old children from Russia and former USSR of the second part of XX century (literary data). Each sample has minimal necessary number of statistical characteristics: number of sex/age groups, means and standard deviations for height, weight, chest girth. The quantitative estimation of SD level is performed using Kullback divergence, the analogue of Makhalanobis distance. To estimate the direction and the level of associations of SD of anthropometric traits and ecological parameters the classic correlation analysis for pair combinations of indices in age groups of 3- and 6-year-old children was used. Results. For the compact block of Slavonic samples, examined in 1960s–1970s, the increase of the level of the quantity of population of the residence place is associated with significant decrease of SD of height and SD of weight. The same association for 3-year-old children has the character of tendency, but the same vector of dynamics. SD of chest girth has some small negative significant correlations with the latitude for 3-year-old children and close to significant level for 6-year-old children. The estimation of comparable dynamics of SD of somatic traits in pairs of rural and urban samples of the same region revealed less meanings of SD of height and weight of urban children, that is higher synchrony of growth processes of sexes through the increase of the level of urbanization. Conclusion. The decrease of SD of height/weight parameters and greater sex synchrony of growth dynamics apart with increase of the level of urbanization of the residence place may be the result of better quality of the urban environment (medicine service, nutrition quality, social family status). The decrease of the level of SD of chest girth apart with the increase of the values of geographic latitude witness to the greater sex uniformity of adaptive reactions to the more extremal climatic conditions. @ 2023. This work is licensed under a CC BY 4.0 license.