The socio-ecological correlates of cross-cultural variation in lactase persistence, sexual dimorphism in stature, and wealth inheritance in Africa were investigated, using phylogenetic comparative methods to control for the non-independence of populations (Galton's problem). Felsenstein's method of comparative analysis using independent contrasts, and Pagel's phylogenetic maximum likelihood model, were used. Genetic and linguistic trees were used as models of the past relationships among populations. Lactase persistence was found to be associated with pastoralism but not with solar intensity or aridity. This is consistent with the hypothesis that high lactose digestion capacity in adults is an adaptation to dairying. This result does not support the hypotheses that low solar radiation at high latitudes and aridity are additional selective pressures for lactase persistence. Cross-cultural variation in stature was associated with women's work. Women are taller, relative to men, in societies where women contribute more to subsistence. In Africa, patrilineal wealth inheritance is associated with pastoralism and polygyny. Patrilineal wealth inheritance is adaptive if inherited wealth benefits sons more than daughters, which is probably the case in both polygynous and pastoralist societies. It is hypothesised that matrilineal inheritance arises from wealth inheritance to daughters. Inheritance to daughters is adaptive if the additional benefits of wealth inheritance to sons do not outweigh the risk of paternity uncertainty of sons' offspring. The transmission, between populations, of those bio-cultural traits in the comparative analyses was also investigated. The association between each trait in a population, and that trait in the population's phylogenetic sister-group and nearest geographical neighbour(s) were compared using regression. The majority of traits were found to be associated with phylogeny. Some traits showed an additional association with geographical neighbours. Vertical transmission, from `mother' to `daughter' populations, appears to be more important than geographical diffusion between neighbouring populations, for the majority of the traits tested here.

This study deals with the contribution of the genetic variant lactase persistence among Neolithic people from the Baltic Island Öland. Skeletal remains from twelve individuals went through DNA sequencing in order to find the mutation that allows adult individuals to digest milk sugar. The twelve individuals were chosen from two different Neolithic sites, where the archaeological and isotopic data suggest that the individuals from Köpingsvik were hunters and gatherers and the individuals from Resmo were early farmers. The individuals with the genetic variant lactase persistence can be described with selection and genetic flow.  Only five individuals produced results and the mutation was found in two of the subjects. All the individuals who were successfully sequenced came from Resmo, whereasno individuals from Köpingsvik yielded any results.

Lactase persistence (LP) is a genetically determined trate caused by the expression of lactase in adulthood. Lactase is the intestinal enzyme responsible for digestion of milk sugar, lactose. Its production in the small intestine decreases during the childhood, this physiological condition is called lactose intolerance. However, in some individuals production of this enzyme is not stopped. The persistence of lactase activity is a recent phenomenon, which arose independently in several parts of the world over the past roughly 10,000 years, in connection with the emergence of agriculture, specifically milk production and is (likely) still under strong selection pressure. LP was first observed in Europe, where it is associated with a mutation -13 910*T. Frequency of this mutation correlates with latitude. In Africa, the presence of LP is conversely associated with herding and falls under the hypothesis of genetic and cultural co-evolution associated with cattle and the use of secondary food sources. Pastoral populations living in different areas of Africa have different LP mutations that are linked to their origin. Although many investigation on LP have already been carried out, neither analysed the Tuareg populations. This study is focused on the analysis LP mutations in 93 samples of Tuaregs from...

In addition to the interaction of evolutionary forces, the population history of the African Sahel and Arabia has been influenced by the spread of Neolithic cultural innovations. The reflection of these processes today is a very complex structured diversity of the current populations, which is presented here through the analysis of several genetic markers. The aim is to provide a comprehensive view of the history of demographic processes in the Sahel and Arabia, by combining genetic, linguistic, subsistence and geographical data obtained from local populations. A study of a large dataset of mtDNA sequences showed that Arabia was a major crossroads in gene flow, and although it was colonized by anatomically modern humans from East Africa, today's differentiation from Africa is greater than the differentiation between local populations in these regions. Even the Sahel was an important biocorridor in the past. Today, we encounter populations of various subsistence strategies (nomadic pastoralists and settled farmers), between which gene flow has been severely restricted. A comparison of uniparently inherited loci in both groups points to different migratory activity in the eastern and western parts of the Sahel. Analyzes of Alu elements, which indicated the inclination of West African herders (Fulbs)...