Investigating sex-biased migration during the Neolithic transition in Europe, using an explicit spatial simulation framework

Cultural practices can deeply influence genetic diversity patterns. The Neolithic transitions that took place at different times and locations around the world led to major cultural and demographic changes that influenced and therefore left their marks on human genetic diversity patterns. Several studies on the European Neolithic transition suggest that mitochondrial DNA (mtDNA) and Y-chromosome data can exhibit different patterns, which could be owing to different demographic histories for females and males. Archaeological and anthropological data suggest that the transition from hunter-gatherers (HGs) to farmers' societies is probably associated with changes in social organization, particularly in post-marital residence (PMR) rules (i.e. patrilocality, matrilocality or bilocality). The movements of humans and genes associated with these rules can be seen as sex-biased short-range migrations. We developed a new individual-based simulation approach to explore the genetic consequences of 45 different scenarios, where we varied the patterns of PMR and admixture between HGs and farmers. We recorded mtDNA and Y-chromosome data and analysed their diversity patterns within and between populations, through time and space. We also collected published mtDNA and Y-chromosome data from European and Near-Eastern populations in order to identify the scenarios that would best explain them. We show that: (i) different PMR systems can lead to different patterns of genetic diversity and differentiation, (ii) asymmetries between mtDNA and Y-chromosome can be owing to different behaviours between males and females, but also to different mutations rates, and (iii) patrilocality in farmers explains the present patterns of genetic diversity better than matrilocality or bilocality. Moreover, we found that (iv) the genetic diversity of farmers change depending on the HGs PMR rules even though they are assumed to disappear more than 5000 years ago in our simulations.     

Frequencies of functional caspase 12 genotypes in the North Africa population

Caspase 12(Csp-12) is a cysteine protease that plays a role in regulation of cytokine maturation. It is present either in a functional full-length variant (Csp-12L) that predisposes to a lower immune response or in an inactive, common version (Csp-12S) that contains a stop codon that results in a truncated form. Genomic DNA from unrelated North Africans, residents of 4th Nile Cataract Region in Sudan, was analyzed. One hundred umbilical blood samples of Polish newborns served as a reference group from the Caucasian population. The analysis of stop-codon polymorphism performed on the 212 human samples from Northern Sudan identified 6.6% individuals with heterozygous genotypes while not one homozygous Csp-12L was found. All examined Polish individuals were homozygous Csp-12S.     

The Enchytraeid fauna of North Africa

As part of a survey of the Mediterranean enchytraeids, large numbers of samples were collected from a wide range of habitats at 38 localities of Tunisia and Algeria in 1989. Twenty species were identified belonging to six genera. Five species are new records for Tunisia and 17 are new for Algeria. Most of the recorded species are widely distributed throughout Europe, or even cosmopolitan, but some have a more restricted range. Fridericia caprensis has a circummediterranean distribution, Fridericia sardorum seems to be endemic to the western Mediterranean and Fridericia berninii is known only from the Balearic Islands and Algeria. Enchytraeus minutus bisetosus n. ssp. is described. A critical revision of some species is also provided.     

Neolithic dairy farming at the extreme of agriculture in northern Europe

The conventional ‘Neolithic package’ comprised animals and plants originally domesticated in the Near East. As farming spread on a generally northwest trajectory across Europe, early pastoralists would have been faced with the challenge of making farming viable in regions in which the organisms were poorly adapted to providing optimal yields or even surviving. Hence, it has long been debated whether Neolithic economies were ever established at the modern limits of agriculture. Here, we examine food residues in pottery, testing a hypothesis that Neolithic farming was practiced beyond the 60th parallel north. Our findings, based on diagnostic biomarker lipids and δ¹³C values of preserved fatty acids, reveal a transition at ca 2500 BC from the exploitation of aquatic organisms to processing of ruminant products, specifically milk, confirming farming was practiced at high latitudes. Combining this with genetic, environmental and archaeological information, we demonstrate the origins of dairying probably accompanied an incoming, genetically distinct, population successfully establishing this new subsistence ‘package’.     

Genie differentiation in M. m. domesticus populations from Europe, the Middle East and North Africa: geographic patterns and colonization events

Geographic patterns of genie differentiation were investigated in the commensal house mouse subspecies, M. m. domesticus . The analysis by protein electrophoresis of 40 populations throughout Europe, the Middle East and North Africa indicated that genie differentiation was not highly structured on a macrogeographic scale. Mean genie distances between regions showed, however, that populations fell into three levels of differentiation: a low level in southern Europe within which interregional distances were no larger than intraregional ones, an intermediate level between southern European populations and North European and African ones, and finally, a higher level between all the latter and the Middle Eastern populations.
Gene flow estimates indicated that the homogeneity of southern European populations does not result from present high levels of gene flow, but more likely from a very recent ancestry. These data when argumented with the fossil records of mice from the Mediterranean Basin suggest a two-step colonization process, the most recent of which occurred very rapidly and resulted in the multiple founding of populations in southern Europe. The relationship of M. m. domesticus to other subspecies of mice is discussed in relation to introgression and taxonomy.
Microdifferentiation patterns with low levels of within population substructuring and of gene flow suggest that genie differentiation in the western European house mouse is largely determined by genetic drift and/or founder effects. Although historical factors are determinant in the large scale patterns of genie variation in commensal house mice, dispersal by man no longer seems to be a prominent feature moulding the genetic structure of M. m. domesticus .     

Anthropological structure and culture adaptive strategies of the Neolithic Populations in Central Europe

The present work is the outcome of both biological anthropology and prehistoric research. The theses of cultural ecology became the basis for research on biological and cultural changes of human groups. More than 80 human bones series from the Neolithic cultures of Central Europe have been used here. The role of economic processes (ie: the additional role of cultural system) within the general picture of a given system has been stressed here. As far as anthropological analysis is concerned, the estimation of biological population state and dynamics and the morphological characteristics including the skull morphology, have been used in the present work. In order to observe the mutual interrelations 2 developmental systems for 2 cultural units, the Linear Pottery Culture and the Corded Ware Culture have been constructed. As we think there 2 systems present 2 different adaptational strategies in the Neolithic in Central Europe. The adaptational strategy is understood as socially generated concept of the creation of man-and-environment relation.     

Spreading Waves in a Farmers and Hunter-Gatherers Model of the Neolithic Transition in Europe

The Neolithic transition began the spread of early agriculture throughout Europe through interactions between farmers and hunter-gatherers about 10,000 years ago. Archeological evidence produced by radiocarbon dating indicates that the expanding velocity of farming is roughly constant all over Europe. Theoretical understanding of such evidence has been performed from mathematical modeling viewpoint. However, the expanding velocity determined by existing modeling approaches is faster than the observed velocity. For understanding this difference, we propose a three-component reaction–diffusion system which consists of two different types of farmers (sedentary and migratory) and hunter-gatherers from the viewpoint of the influence of farming technology. Our purpose is to study the relation between the expanding velocity of farmers and the farming technology parameter (say, \(\gamma \)). In this paper, we mainly focus on the one-dimensional traveling wave solution with minimal velocity and show that the minimal velocity decreases, as \(\gamma \) increases. This can be compatible with the observed velocity when farming technology is developed. Our results suggest that the reason for the slowdown of the Neolithic transition might be related to the increase in the development of farming technology.