Fluctuating asymmetry of human morphometric features as a marker of developmental instability caused by adverse environmental conditions.

Abstract

Background: This article is an attempt to apply fluctuating asymmetry as amorphometric method of studying changes in specific structures of the right and the left side of the body to determine variables which may affect morphogenesis and, consequently, human morphology in adulthood. The main aim of this study was to use the fluctuating asymmetry level as an indicator of adverse living conditions in childhood by determining the impact of environmental components (socio-economic factors and air pollution) on the level of body asymmetry in young women and men.

Materials and methods: Data were collected from 877 students from various Polish universities, including 483 women and 394 men. Anthropometric data and questionnaire responses were recorded. As part of the surveys, respondents provided information about their place of residence, socio-economic status and lateralisation. The composite body FA (cFA) was assessed based on six bilateral features: the length of fingers II and IV of both hands, the length and width of the ear, and the length and width of the foot.

Results and conclusions: The present study supports the hypothesis that asymmetry increases as socioeconomic status decreases and air pollution levels increase. Differences in asymmetry, depending on environmental factors, socioeconomic status (SES) and air quality, were in most cases greater in men than in women. The results confirm that variable asymmetry is a sensitive indicator of an individual's exposure to unfavorable environmental factors during ontogenesis. Moreover, the results of the conducted research suggest that environmental factors may influence the structure of the human body, and irreversible morphological alterations are the result of unfavorable conditions occurring in the early stages of biological development.