How collective behaviour evolves — new theory paper

Collective behaviour is everywhere in nature: birds flock, fish shoal, cells coordinate, even molecules “team up.” These patterns arise when simple local rules between individuals produce complex group-level outcomes.

But why do such behaviours evolve, especially in groups where members aren’t close relatives?

In this paper I develop a new theory showing that, under certain conditions, group-level benefits alone can drive the evolution of coordinated collective behaviour – even when group members aren’t closely related. I link classic social-evolution tools with models of collective motion, revealing when and why the “rules” individuals follow (like alignment or crowding) will spread through populations.

To push the theory beyond pen and paper, I outline how it can be tested in cutting-edge bio-hybrid experiments, where real animals interact with virtual or robotic partners. These systems let us watch natural selection act on collective behaviour in real time.

By fusing social-evolution theory with the science of collective motion, this work lays the foundations for a predictive, evolutionary understanding of cooperation across scales – from molecules and cells to flocks, herds, and human crowds.

Read the full paper: https://www.sciencedirect.com/science/article/pii/S0003347225000880