Asthenic type and debrachycephalization

[Agrippa]

In Monatsschr Kinderheilkd 2002 · 150:1273–1277 DOI 10.1007/s00112-002-0570-4

Transformation of body and head shape in Moscow schoolchildren: secular aspects

Godina EZ

Based on the results of several successive cross-sectional studies of Moscow schoolchildren, secular changes in body and head dimensions have been investigated.Data on children from 8 to 17 measured in the 1970’s, 1980’s and 1990’s (all in all about 10,000 individuals) have been compared. Some historical data on growth and development of children from the 1940’s and 1960’s have also been used for comparative purposes. [...] Possible causes of debrachicephalization are discussed. The argument is that this is a part of astenization and leptosomization processes, which go along with secular changes. This trend is revealed not only by recent data but also in the course of human evolution (Khrissanfova, 2002). Distribution of somatotypes (evaluated by Shtefko-Ostrovsky method) show the increasing frequencies of the so-called “astenoid”(ectomorph) type in the latest series (particularly in the 1990’s). The analysis of intra-group variability has shown that among somatotypes the most pronounced secular changes are typical for children of the astenoid type. They have the highest values of canonic correlation coefficients between head and face, and body measurements. This may suggest a “resonance” response of this particular type to secular changes.

Dienekes\' Anthropology Blog: Asthenic type and debrachycephalization

I think that certain racial and constitional variants (f.e. leptomorphs in general, Nordid and Mediterranid in general) react the most and strongest if its about certain environmental changes.
Those grow stronger and with the typical allometric correlations once the environmental conditions become better again and their change is so drastic that they influence the whole average so much that one could assume a much greater general change. But in fact they change much more than other variants which have much less potential in the same direction (height growth, elongation, debrachycephalisation etc.) and being just pushed statistically in the same direction with their little alterations because of the massive change of the leptomorphic and leptomorph-mesomorphic variants in particular.