Jouault Corentin, Condamine Fabien L, Legendre Frédéric, Perrichot Vincent
Institut de Systématique Évolution, Biodiversité, UMR 7205, Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE-PSL, Université des Antilles, Paris 75005, France.
Institut des Sciences de l'Évolution de Montpellier, Université de Montpellier, CNRS, Montpellier 34095, France.
Proc Natl Acad Sci U S A. 2024 Mar 26;121(13):e2317795121. doi: 10.1073/pnas.2317795121. Epub 2024 Mar 11.
With 14,000 extant species, ants are ubiquitous and of tremendous ecological importance. They have undergone remarkable diversification throughout their evolutionary history. However, the drivers of their diversity dynamics are not well quantified or understood. Previous phylogenetic analyses have suggested patterns of diversity dynamics associated with the Angiosperm Terrestrial Revolution (ATR), but these studies have overlooked valuable information from the fossil record. To address this gap, we conducted a comprehensive analysis using a large dataset that includes both the ant fossil record (24,000 individual occurrences) and neontological data (~14,000 occurrences), and tested four hypotheses proposed for ant diversification: co-diversification, competitive extinction, hyper-specialization, and buffered extinction. Taking into account biases in the fossil record, we found three distinct diversification periods (the latest Cretaceous, Eocene, and Oligo-Miocene) and one extinction period (Late Cretaceous). The competitive extinction hypothesis between stem and crown ants is not supported. Instead, we found support for the co-diversification, buffered extinction, and hyper-specialization hypotheses. The environmental changes of the ATR, mediated by the angiosperm radiation, likely played a critical role in buffering ants against extinction and favoring their diversification by providing new ecological niches, such as forest litter and arboreal nesting sites, and additional resources. We also hypothesize that the decline and extinction of stem ants during the Late Cretaceous was due to their hyper-specialized morphology, which limited their ability to expand their dietary niche in changing environments. This study highlights the importance of a holistic approach when studying the interplay between past environments and the evolutionary trajectories of organisms.
蚂蚁现存约14000种，分布广泛，具有极其重要的生态意义。在其整个进化历史中，它们经历了显著的多样化。然而，其多样性动态的驱动因素尚未得到充分量化或理解。先前的系统发育分析表明了与被子植物陆地革命（ATR）相关的多样性动态模式，但这些研究忽略了化石记录中的宝贵信息。为了填补这一空白，我们使用了一个大型数据集进行了全面分析，该数据集既包括蚂蚁化石记录（约24000个个体记录），也包括现代生物数据（约14000个记录），并检验了针对蚂蚁多样化提出的四个假说：共同多样化、竞争性灭绝、超专业化和缓冲灭绝。考虑到化石记录中的偏差，我们发现了三个不同的多样化时期（晚白垩世、始新世和渐新世-中新世）和一个灭绝时期（晚白垩世）。干群蚂蚁和冠群蚂蚁之间的竞争性灭绝假说未得到支持。相反，我们发现共同多样化、缓冲灭绝和超专业化假说得到了支持。由被子植物辐射介导的ATR环境变化，可能通过提供新的生态位，如森林凋落物和树栖筑巢地点以及额外资源，在缓冲蚂蚁灭绝和促进其多样化方面发挥了关键作用。我们还推测，晚白垩世干群蚂蚁的衰退和灭绝是由于其超专业化的形态，这限制了它们在不断变化的环境中扩大饮食生态位的能力。这项研究强调了在研究过去环境与生物进化轨迹之间的相互作用时采用整体方法的重要性。
