Assortative Mating: Encounter-Network Topology and the Evolution of Attractiveness

TL;DR

This paper models how social network topology and mate selectivity influence positive assortative mating and the evolution of attractiveness, revealing that higher connectivity and choosiness enhance attractiveness correlation among mates.

Contribution

It introduces a probabilistic encounter-network model linking network structure and mate selection to the evolution of attractiveness, highlighting the roles of degree and choosiness.

Findings

Higher mean degree increases assortative mating strength.

Greater choosiness during pairing enhances attractiveness correlation.

Attractiveness evolution balances selection and offspring distribution skew.

Abstract

We model a social-encounter network where linked nodes match for reproduction in a manner depending probabilistically on each node`s attractiveness. The developed model reveals that increasing either the network`s mean degree or the ``choosiness`` exercised during pair-formation increases the strength of positive assortative mating. That is, we note that attractiveness is correlated among mated nodes. Their total number also increases with mean degree and selectivity during pair-formation. By iterating over model mapping of parents onto offspring across generations, we study the evolution of attractiveness. Selection mediated by exclusion from reproduction increases mean attractiveness, but is rapidly balanced by skew in the offspring distribution of highly attractive mated pairs.