Department of Integrative Marine Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121, Napoli, Italy.
Laboratorio de Investigaciones Marinas y Acuicultura (LIMIA) Govern de les Illes Balears, Av. Gabriel Roca 69, 07158, Port d'Andratx - Mallorca, Spain.
Sci Rep. 2017 Jun 23;7(1):4180. doi: 10.1038/s41598-017-03926-z.
Anchovies represent the largest world's marine fish catches and the current threats on their populations impose a sustainable exploitment based on sound scientific information. In the European anchovy (Engraulis encrasicolus), the existence of several populations has been proposed but a global view is missing. Using a multidisciplinary approach, here we assessed the divergence among different ecotypes and its possible causes. SNPs have revealed two functionally distinct ecotypes overlapping in the Central Mediterranean, with one ecotype confined near the river estuaries. The same SNPs outliers also segregated two distinct populations in the near Atlantic, despite their large spatial distance. In addition, while most studies suggested that adaptation to low salinity is key to divergence, here we show that the offshore ecotype has higher environmental tolerance and an opportunistic feeding behaviour, as assessed by the study of environmental conditions, anchovy diet and trophic levels, and passive egg dispersal. These results provide insights into the anchovy evolutionary history, stressing the importance of behaviour in shaping ecotypes.
凤尾鱼是世界上捕获量最大的海洋鱼类，目前凤尾鱼种群面临的威胁要求我们在有可靠科学信息的基础上进行可持续开发。在欧洲凤尾鱼（Engraulis encrasicolus）中，已经提出了存在多个种群的假设，但缺乏全球视角。本研究采用多学科方法，评估了不同生态型之间的差异及其可能的原因。单核苷酸多态性（SNP）揭示了两种在中地中海重叠的具有不同功能的生态型，其中一种生态型局限于河口附近。同样的 SNP 异常值也在近大西洋地区分离出两个不同的种群，尽管它们的空间距离很大。此外，尽管大多数研究表明，对低盐度的适应是分化的关键，但本研究表明，近海生态型具有更高的环境耐受性和机会主义的摄食行为，这可以通过对环境条件、凤尾鱼的饮食和营养级以及被动卵扩散的研究来评估。这些结果为凤尾鱼的进化历史提供了新的认识，强调了行为在塑造生态型方面的重要性。
