Original paper
The secular trend and network effects on height of male Japanese students from 1955 to 2015
Bents, Dominik; Groth, Detlef; Satake, Takashi
Anthropologischer Anzeiger Volume 74 No. 5 (2018), p. 423 - 429
published: Jun 1, 2018
published online: Apr 18, 2018
manuscript accepted: Feb 19, 2018
final revised version received: Feb 13, 2018
manuscript revision requested: Jan 15, 2018
manuscript received: Dec 19, 2017
DOI: 10.1127/anthranz/2018/0838
Open Access (paper may be downloaded free of charge)
Abstract
Abstract Introduction: Body height is influenced by biological factors such as genetics, nutrition and health, but also by the social network, and environmental and economical factors. During centuries, the Japanese society has developed on islands. This setting provides ideal natural conditions for studying the influence of social networks on human height. Material and methods: We investigated body height of male Japanese students aged 17.5 years obtained in 47 prefectures, from the Japanese school health survey of the years 1955, 1975, 1995, and 2015. Results: Japanese students increased in height from 163.23 cm in 1955 to 170.84 cm in 1995, with no further increase thereafter (170.63 cm in 2015). Students living in neighboring prefectures were similar in height. The correlation of height between neighboring prefectures ranged between r = 0.79 and r = 0.49 among first degree neighbors, between r = 0.49 and r = 0.21 among second degree neighbors and dropped to insignificance among third degree neighbors indicating psychosocial effects of the community on body height. Tall stature and short stature prefectures did not remain tall or short throughout history. Autocorrelations of height within the same prefectures decreased from the 20 years periods of 1955–1975, 1975–1995 and 1995–2015 (r = 0.52, r = 0.61, r = 0.63, respectively) to the 40 years periods of 1955–1995 and 1975–2015 (r = 0.49, r = 0.52), down to the 60 years period of 1955–2015 (r = 0.27), indicating significant volatility of height. Conclusion: Body height of 17.5 years old Japanese students increased since 1955. Body height depended on height of the neighboring prefecture, but was volatile with decreasing autocorrelation during a period of 60 years.
Keywords
body height • community effect • neighbor correlation • Japan