In palaeontological studies, groups with consistent ecological and morphological traits across a clade’s history (functional groups)¹ afford different perspectives on biodiversity dynamics than do species and genera^2,3, which are evolutionarily ephemeral. Here we analyse Triton, a global dataset of Cenozoic macroperforate planktonic foraminiferal occurrences⁴, to contextualize changes in latitudinal equitability gradients¹, functional diversity, palaeolatitudinal specialization and community equitability. We identify: global morphological communities becoming less specialized preceding the richness increase after the Cretaceous–Palaeogene extinction; ecological specialization during the Early Eocene Climatic Optimum, suggesting inhibitive equatorial temperatures during the peak of the Cenozoic hothouse; increased specialization due to circulation changes across the Eocene–Oligocene transition, preceding the loss of morphological diversity; changes in morphological specialization and richness about 19 million years ago, coeval with pelagic shark extinctions⁵; delayed onset of changing functional group richness and specialization between hemispheres during the mid-Miocene plankton diversification. The detailed nature of the Triton dataset permits a unique spatiotemporal view of Cenozoic pelagic macroevolution, in which global biogeographic responses of functional communities and richness are decoupled during Cenozoic climate events. The global response of functional groups to similar abiotic selection pressures may depend on the background climatic state (greenhouse or icehouse) to which a group is adapted.

在古生物学研究中，在进化枝历史上具有一致的生态和形态特征的群体（功能群体）^{1与物种和属2,3}相比，在生物多样性动态方面提供了不同的视角，而物种和属在进化上是短暂的。在这里，我们分析 Triton（新生代大孔浮游有孔虫现象的全球数据集^{4 ）}，以了解纬度公平梯度¹、功能多样性、古纬度专业化和群落公平性的变化。我们发现：在白垩纪-古近纪灭绝之后，全球形态群落在丰富度增加之前变得不那么专业化；早始新世气候最适期期间的生态专业化，表明新生代温室高峰期间赤道温度受到抑制；由于始新世-渐新世过渡期间的循环变化，在形态多样性丧失之前，专业化程度增加；大约 1900 万年前形态特化和丰富度的变化，与远洋鲨鱼灭绝同时期⁵；在中中新世浮游生物多样化过程中，半球之间功能群丰富度和专业化变化的延迟发生。 Triton 数据集的详细性质允许对新生代中上层宏观演化进行独特的时空观察，其中功能群落和丰富度的全球生物地理响应在新生代气候事件期间是分离的。功能群体对类似非生物选择压力的整体反应可能取决于群体所适应的背景气候状态（温室或冰库）。