Marriage, mining and mobility: four Durham parishes

Abstract

Population Genetics theory suggests that gene flow plays a prominent role in reducing genetic heterogeneity in a species. This project attempted to assess the opportunity for gene flow in an eastern Durham population in the ~nineteenth century by measuring the migration that is associated with marriage, then utilised these observations to predict changes in the genetical structure of the population. The marrriage data, obtained from Anglican Parish registers (1797-1876) and the 1851 Census, were analysed in the form of migration matrices '17hich predicted the time taken for two places to become related and therefore genetically uniform. Coal-mining transformed the four parishes of the study area from an agricultural~ sparsely populated region to a populous industrial complex. Historical observations suggested that this 'nev1' population was both spatially and socially distinct from the rural one and this was confirmed by the matrix analysis that indicated strong positive assortment for occupation which, it was thought, would lead to a 'patchy' distribution of genetical traits. The relative merits of the two data sources, the defects in the matrix technique and the implications for other industrial areas were discussed.