Macroecological diversification of ants is linked to angiosperm evolution

The success of numerous lineages has at least in part been attributed to shifts in vegetation. The evolutionary history of ants-an abundant, diverse, and widespread lineage-is deeply entwined with the evolution and spread of flowering plants. Here we further characterize the ecological diversification of ants in the context of flowering plants and biome evolution by determining when ants expanded outward from forested to non-forested biomes, and how the evolution of climatic niche is related to arboreal nesting. The Paleogene-Neogene spread of ants into non-forested biomes likely followed the evolution and expansion of arid-adapted angiosperms that provided food to ants. Shifts to arboreal nesting tracked evolutionary innovations in angiosperm physiology linked to the evolution of everwet tropical rainforests. Differences in climatic optima and climatic niche evolution were also linked to nesting location with arboreal nesters having warmer and less seasonal climatic optima coupled with lower rates of climatic niche evolution. Our results contribute new insights into the diverse means by which flowering plant evolution shaped the ecology and evolution of associated lineages.

Automated summary

The success of various lineages is partly due to changes in vegetation. The evolutionary history of ants is closely associated with the evolution and spread of flowering plants. This study investigates the diversification of ants in relation to flowering plants and biome evolution, focusing on their expansion from forested to non-forested biomes and the relationship between climatic niche evolution and arboreal nesting. The spread of ants into non-forested biomes during the Paleogene-Neogene era was likely driven by the evolution and expansion of arid-adapted angiosperms, providing food for ants. The choice of nesting location in trees is linked to evolutionary innovations in angiosperm physiology and the establishment of everwet tropical rainforests. Differences in climatic optima and climate niche evolution are also associated with nesting location, with arboreal nesters preferring warmer and less seasonal climates and exhibiting slower rates of climatic niche evolution. This research offers new insights into the impact of flowering plant evolution on the ecology and evolution of associated lineages.