Zhang Zhutong, Yang Chuan, Sahy Diana, Zhan Ren-Bin, Wu Rong-Chang, Li Yang, Deng Yiying, Huang Bing, Condon Daniel J, Rong Jiayu, Li Xian-Hua
State Key Laboratory of Lithospheric and Environmental Coevolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China.
College of Earth and Planetary Science, University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Adv. 2025 May 30;11(22):eadv6788. doi: 10.1126/sciadv.adv6788.
The Late Ordovician mass extinction (LOME) included two phases (I and II) of high species turnover that have been hypothetically linked to the Hirnantian glaciation and subsequent rapid warming, respectively. However, the timing and tempo of the LOME remain uncertain, which hinders our understanding of the feedback between the LOME and paleoclimatic change. Here, we present high-precision radioisotopic dates for the Ordovician-Silurian transition in South China that reveal the LOME began at 442.76 + 0.35/-0.22 million years ago, with the two phases lasting for 0.34 + 0.46/-0.34 and 0.06 + 0.31/-0.06 million years, respectively. The rapid switch from icehouse to greenhouse conditions, along with the higher mean rate of temperature change during LOME II, resulted in a much higher mean extinction rate during LOME II than I (71.6% versus 8.4% species loss per 100 thousand years, respectively), implying that the rate of climate change was a primary control on the tempo of the LOME.
晚奥陶世大灭绝（LOME）包括两个物种更替率较高的阶段（阶段I和阶段II），据推测分别与赫南特冰期和随后的快速变暖有关。然而，LOME的时间和节奏仍不确定，这阻碍了我们对LOME与古气候变化之间反馈的理解。在此，我们给出了中国南方奥陶纪-志留纪过渡时期的高精度放射性同位素年代，结果显示LOME始于442.76 ± 0.35/-0.22百万年前，两个阶段分别持续了0.34 ± 0.46/-0.34百万年和0.06 ± 0.31/-0.06百万年。从冰室状态到温室状态的快速转变，以及LOME II期间更高的平均温度变化速率，导致LOME II期间的平均灭绝率远高于阶段I（每10万年分别有71.6%和8.4%的物种灭绝），这意味着气候变化速率是LOME节奏的主要控制因素。
