加拿大维多利亚大学Erin Foster团队取得一项新突破。他们的研究发现由海獭数量恢复产生的物理干扰增加了鳗草的遗传多样性。2021年10月15日，国际学术期刊《科学》发表了这一成果。

研究人员报告了海獭（Enhydra lutris）在鳗草（Zostera marina）草甸中挖掘内陆猎物所产生的干扰如何通过促进植物有性繁殖的条件来增加遗传多样性。在恢复海獭种群保护地建立20至30年的地区，鳗草等位基因丰富度和基因型多样性分别比它们存在<10年或消失>100年的地区高30%和6%。海獭栖息地对上述遗传多样性测量的影响强于深度、温度、纬度或草地大小的影响。

该研究结果揭示了一个未被充分认识的进化过程，巨型动物可能通过该过程促进遗传多样性和生态恢复力。

据介绍，大多数关于捕食者作用的认识本质上是自然稳态的结果。

附：英文原文

Title: Physical disturbance by recovering sea otter populations increases eelgrass genetic diversity

Author: Erin Foster, Jane Watson, Matthew A. Lemay, M. Tim Tinker, James A. Estes, Rebecca Piercey, Lauren Henson, Carol Ritland, Allyson Miscampbell, Linda Nichol, Margot Hessing-Lewis, Anne K. Salomon, Chris T. Darimont

Issue&Volume: 2021-10-15

Abstract: Most knowledge regarding the role of predators is ecological in nature. Here, we report how disturbance generated by sea otters (Enhydra lutris) digging for infaunal prey in eelgrass (Zostera marina) meadows increases genetic diversity by promoting conditions for sexual reproduction of plants. Eelgrass allelic richness and genotypic diversity were, respectively, 30 and 6% higher in areas where recovering sea otter populations had been established for 20 to 30 years than in areas where they had been present <10 years or absent >100 years. The influence of sea otter occupancy on the aforementioned measures of genetic diversity was stronger than those of depth, temperature, latitude, or meadow size. Our findings reveal an underappreciated evolutionary process by which megafauna may promote genetic diversity and ecological resilience.

DOI: abf2343

Source: https://www.science.org/doi/10.1126/science.abf2343