Model of Genetic Variation in Human Social Networks

TL;DR

This paper demonstrates that certain social network attributes are heritable, introduces a new model explaining this heritability, and challenges existing network models by showing they cannot account for genetic variation.

Contribution

It reveals heritability in social network attributes and proposes the 'Attract and Introduce' model, advancing understanding of genetic influences on social structures.

Findings

Heritability found in in-degree, transitivity, and centrality.

Existing network models do not explain genetic variation.

The new model fits real human social network data.

Abstract

Social networks exhibit strikingly systematic patterns across a wide range of human contexts. While genetic variation accounts for a significant portion of the variation in many complex social behaviors, the heritability of egocentric social network attributes is unknown. Here we show that three of these attributes (in-degree, transitivity, and centrality) are heritable. We then develop a "mirror network" method to test extant network models and show that none accounts for observed genetic variation in human social networks. We propose an alternative "Attract and Introduce" model with two simple forms of heterogeneity that generates significant heritability as well as other important network features. We show that the model is well suited to real social networks in humans. These results suggest that natural selection may have played a role in the evolution of social networks. They also suggest that modeling intrinsic variation in network attributes may be important for understanding the way genes affect human behaviors and the way these behaviors spread from person to person.