Directional and fluctuating asymmetry among ! Kung San and Kavango people of Northern Namibia: The impact of sex and subsistence patterns

Objectives: The impact of sex and subsistence on fluctuating and directional asymmetry patterns was tested among ! Kung San and Kavango people from northern Namibia. Methods: Fluctuating and directional asymmetry from 6 paired traits were measured in a sample of 236 ! Kung San and 248 Kavango people aged 18 to 65 years in the Kavango district and the Nyae-Nyae area of northern Namibia. Signed asymmetry, absolute and relative asymmetry, as well as composite fluctuating and directional asymmetry, were calculated. Results: Males of both ethnic groups exhibited higher fluctuating asymmetry in comparison to their female counterparts. Marked differences in directional asymmetry of the upper extremities were found between ! Kung San and Kavango people. The ! Kung San people showed a significantly higher directional asymmetry than the Kavango people. Conclusions: Foraging subsistence increased directional asymmetry of the upper extremities among males as well as females. In contrast, higher fluctuating asymmetry-indicating a higher degree of developmental instability-was found among males independent of subsistence group.