Abstract:
In order to provide accurate methods for stature estimations, ancestry differences and secular
changes in stature and limb proportions need to be noted. Stature and limb proportion
changes in human population groups are influenced by various genetic and environmental
factors. The purpose of this study was to evaluate ancestry differences and secular changes in
stature and limb proportions of South African population groups and to assess how these
variables differ between individuals from southern and northern hemispheres. The sample
comprised of osteometric and anthropometric data from modern black and white South
Africans (17 and 68 years), North American and white European (Dutch and Swiss)
populations. The sample was divided into birth cohorts of 5 years or 10 years to observe
secular trends. Ancestry differences and secular trends in stature and limb proportions
between South African population groups were compared. Also, differences and secular
trends in stature and limb proportions were compared between white North American and
European groups to determine whether differences exist between the southern and northern
hemisphere groups. Additionally, the differences in stature between black and white South
African and North American groups were compared. It was found that white South Africans
were significantly taller than their black South African counterparts. Significant positive
secular trends in stature were observed in black South African males while non-significant
increases were observed in white South African males and white and black South African
females. The secular trends in European samples are significantly greater than those observed
in white South African males. Black South African groups had greater limb and distal limb
lengths than white South African groups. Proximal limb ratios increased while the distal limb
ratios decreased which suggests that regression formulae to estimate stature need to be
regularly updated. The upper limb ratio and arm ratios were significantly higher in white
South African groups compared to white North American groups. Secular changes are
constantly taking place due to a combination of various factors such as climate, nutrition.
Overall, secular changes in limb proportions indicate a trend where South African groups are
becoming more similar to each other.
