Department of Anthropology, Stony Brook University, Stony Brook, NY, USA.
Department of Biological and Chemical Sciences, New York Institute of Technology, Westbury, NY, USA.
Ann Hum Biol. 2020 Aug;47(5):446-456. doi: 10.1080/03014460.2020.1783361. Epub 2020 Jul 9.
Previous studies of secular change in cranial size among black South Africans have produced conflicting results.
We re-examined cranial size change in this population during the 19th and 20th century by evaluating its relationship with individual year-of-birth, and the significance of trends among eight decennial cohorts.
This study is based on 102 male and 89 female adults born between 1865 and 1959. Linear regressions were employed to evaluate possible relationships between year-of-birth and cranial dimensions; ANOVAs were used to evaluate the significance of long-term trends among decennial cohorts.
No analysis revealed a secular change in cranial length in either sex; however, the ANOVA for cranial length in the combined sex sample was significant. There is no secular trend in female cranial breadth, but males display a negative trend in this dimension. This results in a secular trend for increased male dolichocephaly.
The factors that underlie the negative secular trend in male cranial breadth and the absence of a secular trend in overall cranial size in this population are unclear. Nevertheless, these observations accord with findings related to stature and long bone strength in this population and are consistent with observations for other sub-Saharan African populations.
此前针对南非黑人颅尺寸的长期变化研究得出了相互矛盾的结果。
通过评估个体出生年份与颅尺寸变化的关系，以及 8 个十年组群趋势的意义，重新检验南非黑人在 19 至 20 世纪期间颅尺寸的变化。
本研究基于 1959 年以前出生于 1865 年至 1959 年之间的 102 名男性和 89 名女性成年人。采用线性回归评估出生年份与颅尺寸之间的可能关系；采用方差分析评估十年组群中长期趋势的显著性。
无论男女，均未发现颅长存在长期变化的趋势；但在男女混合样本中，颅长的方差分析具有显著性。女性颅宽无长期变化趋势，但男性的这一维度呈现负向趋势。这导致男性颅型变长的长期趋势。
导致男性颅宽出现负向长期变化趋势以及该人群颅尺寸整体不存在长期变化趋势的因素尚不清楚。然而，这些观察结果与该人群的身高和长骨强度相关发现一致，也与其他撒哈拉以南非洲人群的观察结果一致。
