Ants, with over 14,000 extant species, are ecologically significant and have undergone extensive diversification. This study investigates the factors influencing ant diversification and extinction, focusing on the Angiosperm Terrestrial Revolution (ATR), a period of angiosperm dominance that reshaped ecosystems. Using a combined fossil and neontological dataset, the researchers tested four hypotheses: co-diversification, competitive extinction, hyper-specialization, and buffered extinction. They found three diversification periods (latest Cretaceous, Eocene, Oligo-Miocene) and one extinction period (Late Cretaceous). The competitive extinction hypothesis between stem and crown ants was not supported, while co-diversification, buffered extinction, and hyper-specialization were supported. The ATR likely buffered ants against extinction by providing new ecological niches and resources, favoring diversification. The decline of stem ants during the Late Cretaceous was attributed to hyper-specialization, limiting their adaptability. The study highlights the importance of a holistic approach in understanding the interplay between past environments and evolutionary trajectories. The ATR played a critical role in ant evolution by promoting diversification and reducing extinction risks. The findings challenge the competitive exclusion hypothesis and emphasize the role of environmental changes in shaping ant diversity. The study integrates paleontological and neontological data, using birth-death models to estimate diversification rates and test hypotheses. The results suggest that the ATR's environmental changes, including angiosperm diversification and gymnosperm decline, were key factors in buffering ants against extinction and driving their diversification. The study provides insights into the evolutionary history of ants and underscores the importance of considering broader ecological contexts in understanding diversification patterns.Ants, with over 14,000 extant species, are ecologically significant and have undergone extensive diversification. This study investigates the factors influencing ant diversification and extinction, focusing on the Angiosperm Terrestrial Revolution (ATR), a period of angiosperm dominance that reshaped ecosystems. Using a combined fossil and neontological dataset, the researchers tested four hypotheses: co-diversification, competitive extinction, hyper-specialization, and buffered extinction. They found three diversification periods (latest Cretaceous, Eocene, Oligo-Miocene) and one extinction period (Late Cretaceous). The competitive extinction hypothesis between stem and crown ants was not supported, while co-diversification, buffered extinction, and hyper-specialization were supported. The ATR likely buffered ants against extinction by providing new ecological niches and resources, favoring diversification. The decline of stem ants during the Late Cretaceous was attributed to hyper-specialization, limiting their adaptability. The study highlights the importance of a holistic approach in understanding the interplay between past environments and evolutionary trajectories. The ATR played a critical role in ant evolution by promoting diversification and reducing extinction risks. The findings challenge the competitive exclusion hypothesis and emphasize the role of environmental changes in shaping ant diversity. The study integrates paleontological and neontological data, using birth-death models to estimate diversification rates and test hypotheses. The results suggest that the ATR's environmental changes, including angiosperm diversification and gymnosperm decline, were key factors in buffering ants against extinction and driving their diversification. The study provides insights into the evolutionary history of ants and underscores the importance of considering broader ecological contexts in understanding diversification patterns.