近日，美国哈佛大学Elizabeth C. Sibert等研究人员揭示了中新世早期的远洋鲨鱼灭绝事件。该研究于2021年6月4日发表于国际一流学术期刊《科学》。

研究人员提供了大约1900万年前发生在中新世早期鲨鱼大灭绝事件的证据。在此期间，鲨鱼几乎从公海沉积物中消失了，数量下降了90%以上，形态多样性下降了70%以上，而且它们再也没有从这一事件中恢复过来。这种突然灭绝的发生独立于任何已知的全球气候事件，并且在今天主导远洋生态系统的大型捕食者多样化之前约200万至500万年，这表明中新世早期是公海生态系统的一个快速变革的时期。

据介绍，近几十年来，由于过度捕捞和其他人为压力因素，鲨鱼数量大幅减少；然而，海洋捕食者丰富度和多样性这种变化的长期影响并没有受到很好的限制。

附：英文原文

Title: An early Miocene extinction in pelagic sharks

Author: Elizabeth C. Sibert, Leah D. Rubin

Issue&Volume: 2021/06/04

Abstract: Shark populations have been decimated in recent decades because of overfishing and other anthropogenic stressors; however, the long-term impacts of such changes in marine predator abundance and diversity are poorly constrained. We present evidence for a previously unknown major extinction event in sharks that occurred in the early Miocene, ~19 million years ago. During this interval, sharks virtually disappeared from open-ocean sediments, declining in abundance by >90% and morphological diversity by >70%, an event from which they never recovered. This abrupt extinction occurred independently from any known global climate event and ~2 million to 5 million years before diversifications in the highly migratory, large-bodied predators that dominate pelagic ecosystems today, indicating that the early Miocene was a period of rapid, transformative change for open-ocean ecosystems.

DOI: 10.1126/science.aaz3549

Source: https://science.sciencemag.org/content/372/6546/1105