Centro de Investigación de Estudios Avanzados del Maule, Vicerrectoría de Investigación y Postgrado Universidad Católica del Maule, Talca, Chile; Laboratorio Ecología de Abejas, Departamento de Biología y Química, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca, Chile.
Escuela de Geología, Departamento de Biología y Química, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca, Chile.
Mol Phylogenet Evol. 2024 Jan;190:107945. doi: 10.1016/j.ympev.2023.107945. Epub 2023 Oct 18.
The deep-sea has experienced dramatic changes in physical and chemical variables in the geological past. However, little is known about how deep-sea species richness responded to such changes over time and space. Here, we studied the diversification dynamics of one of the most diverse octocorallian families inhabiting deep sea benthonic environments worldwide and sustaining highly diverse ecosystems, Primnoidae. A newly dated species-level phylogeny was constructed to infer their ancestral geographic locations and dispersal rates initially. Then, we tested whether their global and regional (the Southern Ocean) diversification dynamics were mediated by dispersal rate and abiotic factors as changes in ocean geochemistry. Finally, we tested whether primnoids showed changes in speciation and extinction at discrete time points. Our results suggested primnoids likely originated in the southwestern Pacific Ocean during the Lower Cretaceous ∼112 Ma, with further dispersal after the physical separation of continental landmasses along the late Mesozoic and Cenozoic. Only the speciation rate of the Southern Ocean primnoids showed a significant correlation to ocean chemistry. Moreover, the Paleocene-Eocene thermal maximum marked a significant increase in the diversification of primnoids at global and regional scales. Our results provide new perspectives on the macroevolutionary and biogeographic patterns of an ecologically important benthic organism typically found in deep-sea environments.
深海在地质历史上经历了物理和化学变量的剧烈变化。然而，对于深海物种丰富度如何随时间和空间变化的了解甚少。在这里，我们研究了栖息在世界范围内深海海底环境中并维持高度多样化生态系统的最具多样性的八放珊瑚科之一 Primnoidae 的多样化动态。构建了一个新的基于种的系统发育树，以推断它们最初的地理起源和扩散率。然后，我们测试了它们的全球和区域（南大洋）多样化动态是否受扩散率和生物物理因素（如海洋地球化学变化）的影响。最后，我们测试了 primnoids 是否在离散时间点表现出物种形成和灭绝的变化。我们的研究结果表明，primnoids 可能起源于白垩纪早期（约 1.12 亿年前）的西南太平洋，在中生代和新生代大陆地块的物理分离之后进一步扩散。只有南大洋 primnoids 的物种形成率与海洋化学有显著相关性。此外，古新世-始新世极热事件标志着 primnoids 在全球和区域尺度上的多样化显著增加。我们的研究结果为通常在深海环境中发现的具有重要生态意义的底栖生物的宏观进化和生物地理模式提供了新的视角。
