Landscape heterogeneity and behavioral traits drive the evolution of lion group territoriality

All feline species are territorial, but only African lions defend joint territories. We developed a simulation model to explore the conditions that favor the transition to sociality from a solitary ancestry. Two ecological drivers, population density and landscape heterogeneity, determine the extent to which social groups benefit from monopolizing resource-rich hot spots. However, group territoriality only evolves where individuals remain with their mothers, cooperate to repel neighbors, and expand their territories to maximize access to resources.Group territoriality is exhibited in a diverse range of species and is associated with complex behaviors such as cooperation and altruism. Current hypotheses for the evolutionary transition from solitary to group territoriality consider resource dispersion and population density as the primary drivers. We developed a spatially explicit, agent-based simulation model based on African lions (Panthera leo) to explore the evolution of group territoriality across a range of landscape heterogeneities and population densities. We also examined, within these differing landscapes, how 3 potential behavioral advantages to group territoriality (cooperative defense, increase in territory size, and territorial inheritance) influence the evolution of this trait. Simulation results demonstrate that group territoriality may be an emergent property, which evolves due to synergistic interactions of landscape structure, population density, and behavior. Social individuals were significantly more likely to dominate in both resource-poor and resource-rich, heterogeneous landscapes where individuals exhibit all 3 behavioral traits. Similar environment-behavior interactions may have shaped the evolution of sociality from solitary territoriality across a broad range of taxa.