Kinship networks in shrinking and growing populations

Abstract

We study the structural properties of a class of model social networks representing blood sibling and sibling-in-law relationships, in the case where the size of the married population varies between successive generations. These kinship networks are characterized by Poissonian degree distributions and the presence of a connected component encompassing a large part of the population, along with high values of clustering and assortativity. By means of numerical simulations and comparison with Erdős–Rényi networks of the same size and connectivity, we show that global clustering and assortativity remain high unless the size of the married population drops drastically. In contrast, the largest connected component collapses when the married population shrinks to just about two thirds of its size in the previous generation.