Higher-Order Interactions Can Promote Coexistence by Rewiring Intransitivities Into Competitive Networks.

Higher-order interactions (HOIs) are widely predicted to promote coexistence, yet the underlying ecological mechanisms behind this effect remain largely unexplored in natural communities. Here, we integrate natural history and theory to show how HOIs can restructure competitive networks and influence coexistence. With over 2 years of data on a tropical ant community, we estimate pairwise competitive interactions and demonstrate that, in isolation, they fail to recreate observed community dynamics. We find that inclusion of an HOI, imposed by a parasitoid of the dominant species, can theoretically reorganize competitive networks to mirror the dynamics of the empirical system. We demonstrate how temporal variation in HOIs forces the community between dominance regimes and that the interregnum between regimes is riddled with competitive intransitivities that promote coexistence. This work provides an empirical example of the ecological mechanisms behind the coexistence-promoting effects of HOIs and suggests that HOIs and intransitivity, which are typically treated separately, can be mechanistically linked through the rewiring of species interactions.