The Molecular Clock of Neutral Evolution Can Be Accelerated or Slowed by Asymmetric Spatial Structure
Fig 9
Illustration of idea generation and spreading on Twitter “ego networks”.
Network structure accelerates idea substitution (K > u) if and only if there is a positive spatial correlation between the generation of new ideas (which for our model occurs proportionally to the rate di of incoming ideas) and the probability of fixation ρi. Panels (a) and (b) show the networks with the slowest (K ≈ 0.667u) and fastest (K ≈ 1.085u) rates of idea substitution, respectively, among networks of size 13. The coloration of nodes corresponds to their rate of turnover di, with warmer colors indicating more rapid turnover. The size of nodes corresponds to their fixation probability ρi.