Table 1.

Parameter table

Parameter	Description
Ω	Shared decision parameter – the degree to which collective decisions are shared from 0 = complete control by leaders to 1 = equal share of decisions by leaders and followers
ε	Proportion of leaders in each group. Proportion of followers = 1– ε
N	Number of individuals in each group. Note that N is assumed to be sufficiently large such that Nε is an integer.
V	The value of the contested resource
C	The total cost of losing a conflict
dv	Distribution of V across the classes. Higher values indicate leaders monopolising the resources (Fig. S1)
dc	Distribution of C across the classes. Higher values benefit leaders, in that followers pay the majority of the costs (Fig. S1)

All of the above are defined and fixed at the outset of the model.