近日，英国杜伦大学Harper, David A T在研究奥陶纪末大灭绝事件中取得新进展，研究主要涉及土壤、火和冰三方面。这一研究成果发表在2023年12月18日出版的国际学术期刊《国家科学评论》上。

研究人员在奥陶纪Hirnantian的开始和中部，确定了灭绝的两个阶段。总体来说，这是一次大规模的分类学灭绝，包括一次微弱的系统发育灭绝和一次相对良性的生态灭绝。快速的降温引发了一次大冰期，降低了地表水的温度，导致海平面下降了约100米，并将有毒的底部水引入了大陆架。

这些更基本的行星过程的现象与一系列因素有关，其中一个潜在的驱动因素被确定为火山活动。火山爆发和其他产物可能至少可以追溯到Sandbian和Katian早期，表明这次灭绝的时间比迄今为止记载的持续时间更长，影响更大。

据悉，奥陶纪末大灭绝是“五次大灭绝”中最早的一次，也是最早影响后生动物生命轨迹的一次。

附：英文原文

Title: Late Ordovician Mass Extinction: Earth, fire and ice.

Author: Harper, David A T

Issue&Volume: 2023-12-18

Abstract: The Late Ordovician Mass Extinction was the earliest of the ‘big’ five and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling triggering a major ice age that reduced the temperature of surface waters, prompted a sea level drop of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian suggesting the extinctions were more protracted and influential than hitherto documented.

DOI: 10.1093/nsr/nwad319

Source: https://dx.doi.org/10.1093/nsr/nwad319