Miralles Laura, Oremus Marc, Silva Mónica A, Planes Serge, Garcia-Vazquez Eva
Department of Functional Biology, University of Oviedo, 33006, Oviedo, Spain.
16 rue Henri Niautou, 98800, Noumea, New Caledonia.
PLoS One. 2016 Aug 10;11(8):e0160080. doi: 10.1371/journal.pone.0160080. eCollection 2016.
Pilot whales are two cetacean species (Globicephala melas and G. macrorhynchus) whose distributions are correlated with water temperature and partially overlap in some areas like the North Atlantic Ocean. In the context of global warming, distribution range shifts are expected to occur in species affected by temperature. Consequently, a northward displacement of the tropical pilot whale G. macrorynchus is expected, eventually leading to increased secondary contact areas and opportunities for interspecific hybridization. Here, we describe genetic evidences of recurrent hybridization between pilot whales in northeast Atlantic Ocean. Based on mitochondrial DNA sequences and microsatellite loci, asymmetric introgression of G. macrorhynchus genes into G. melas was observed. For the latter species, a significant correlation was found between historical population growth rate estimates and paleotemperature oscillations. Introgressive hybridization, current temperature increases and lower genetic variation in G. melas suggest that this species could be at risk in its northern range. Under increasing environmental and human-mediated stressors in the North Atlantic Ocean, it seems recommendable to develop a conservation program for G. melas.
领航鲸是两种鲸目动物（巨头鲸和大吻领航鲸），它们的分布与水温相关，且在北大西洋等一些地区部分重叠。在全球变暖的背景下，预计受温度影响的物种会发生分布范围的变化。因此，预计热带领航鲸大吻领航鲸会向北迁移，最终导致种间杂交的次生接触区域和机会增加。在此，我们描述了东北大西洋领航鲸之间反复杂交的遗传证据。基于线粒体DNA序列和微卫星位点，观察到了大吻领航鲸基因向巨头鲸的不对称渗入。对于后一个物种，历史种群增长率估计值与古温度振荡之间存在显著相关性。渗入杂交、当前温度升高以及巨头鲸较低的遗传变异表明，该物种在其北部范围内可能面临风险。在北大西洋日益增加的环境和人为介导的压力源下，为巨头鲸制定一项保护计划似乎是可取的。
