Biotic and Abiotic Constraints on Phenotypic Evolution During Recovery of Planktonic Foraminiferal Diversity After the K/T Boundary Event

白垩纪-第三纪的灭绝见证了许多生物种群的消失，但浮游有孔虫（一种漂浮的单细胞动物种群）作为一个单一的侏儒物种谱系幸存了下来。这些幸存的物种在世界海洋中多样化，是海洋沉积物中常见的微化石。Drs。格塔·凯勒（Gerta Keller）和诺曼·麦克劳德（Norman MacLeod）提议对大灭绝后立即保存下来的幸存谱系进行研究。对它们形态的定量研究将有助于重建祖先-后代关系。对物种多样性模式的分析，以及保存在贝壳材料中的碳和氧同位素比率，将为可能与灭绝和随后的进化辐射同时发生或导致环境变化提供新的见解。这项提议的研究将在所有对灭绝感兴趣的古生物学家、古生态学家和古海洋学家以及一般的进化生物学家中找到广泛的受众。

The Cretaceous-Tertiary extinction witnessed the disappearance of many organismal groups, but the planktonic Foraminifera (a floating one-celled animal group) survived as a single lineage of dwarfed species. These surviving species diversified in the world's oceans and are common microfossils in marine sediments. Drs. Gerta Keller and Norman MacLeod propose a study of the surviving lineages preserved immediately following the extinction. Quantitative study of their morphology will allow reconstruction of ancestor-descendant relationships. Analysis of species diversity patterns, as well as carbon and oxygen isotope ratios preserved in shell material, will provide new insight into the environmental changes that may have coincided with or caused the extinction and subsequent evolutionary radiation. The proposed study will find a wide audience among all paleontologists interested in extinctions, among paleoecologists and paleoceanographers, and among evolutionary biologists in general.