Department of Anatomy and Developmental Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia.
Geosciences, Museums Victoria, Melbourne, VIC, 3001, Australia.
Evolution. 2022 Jun;76(6):1260-1286. doi: 10.1111/evo.14488. Epub 2022 Apr 26.
True seals (phocids) have achieved a global distribution by crossing the equator multiple times in their evolutionary history. This is remarkable, as warm tropical waters are regarded as a barrier to marine mammal dispersal and-following Bergmann's rule-may have limited crossings to small-bodied species only. Here, we show that ancestral phocids were medium sized and did not obviously follow Bergmann's rule. Instead, they ranged across a broad spectrum of environmental temperatures, without undergoing shifts in temperature- or size-related evolutionary rates following dispersals across the equator. We conclude that the tropics have not constrained phocid biogeography.
真海豹（海豹科）在其进化历史中多次穿越赤道，从而实现了全球分布。这是很了不起的，因为温暖的热带水域被认为是海洋哺乳动物扩散的障碍，而且根据伯格曼法则，这种跨越可能仅限于小体型物种。在这里，我们表明，祖先海豹科动物的体型中等，并没有明显遵循伯格曼法则。相反，它们分布在广泛的环境温度范围内，在穿越赤道进行扩散后，其温度或大小相关的进化率并没有发生变化。我们的结论是，热带地区并没有限制海豹科动物的生物地理学分布。
