Biogeographical distributional patterns of cetaceans reflect dispersal events and colonization of the oceans from their ancestral area in the ancient Sea of Tethys ~53 Ma. Likewise, they reveal several vicariance events throughout the evolutionary history of this group. However, our understanding of how these processes took place and what biogeographical scenarios occurred among the different groups of cetaceans through time is limited. Consequently, this work focuses on explaining the distributional patterns of the well‐known North Pacific toothed mysticetes, Aetiocetidae, through the power of retrodiction offered by track analysis (panbiogeography) and cladistic biogeography, using the approach of evolutionary biogeography. Our results show that the distributional patterns of Aetiocetidae explain their endemism in the North Pacific, as well as indicating that their hypothetical ancestor probably colonized the Pacific from the Atlantic Ocean by a dispersal event (founder effect) via the Central American Seaway. Furthermore, their biogeographical history shows that the adaptive radiation (cladogenesis) of Aetiocetidae is result of peripatric speciation followed by sympatric speciation within a heterogeneous environment. Finally, the biogeographical framework of Aetiocetidae further supports the relevant role that the Pacific Ocean has played in the evolution of Oligocene cetaceans as a geographical area that promoted endemism, dispersal and colonization. At more local scales, environmental conditions further promoted increased diversity and disparity amongst Mysticeti.

中文翻译：

---

北太平洋带齿的神秘动物的古生物地理学（鲸科，A科）：渐新世鲸类分布模式的关键

鲸类动物的生物地理分布模式反映了在特提斯海〜53 Ma的祖先地区海洋的扩散事件和殖民化现象。同样，他们揭示了该群体整个进化史上的几次冲突事件。但是，我们对这些过程是如何发生的以及随着时间的推移在不同类别的鲸类动物之间发生了哪些生物地理情况的理解是有限的。因此，这项工作的重点是利用进化生物地理学方法，通过径迹分析（泛生物地理学）和分类生物地理学所提供的追溯力，来解释著名的北太平洋带齿的神秘兽科的分布模式。我们的结果表明，A科的分布模式解释了它们在北太平洋的特有性，并表明他们的假想祖先可能是通过中美洲海上航道的扩散事件（奠基人效应）从大西洋殖民了太平洋。此外，他们的生物地理历史表明，异蝇科的适应性辐射（cladogenesis）是异质环境中的近亲物种形成和同伴物种形成的结果。最后，神仙科的生物地理框架进一步支持了太平洋在渐新世鲸类的进化中所扮演的相关角色，而后者是促进地方性，传播和殖民化的地理区域。在更多地方尺度上，环境条件进一步促进了Mysticeti之间多样性和差异的增加。