School of Marine and Tropical Biology, and Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia.
Proc Biol Sci. 2013 Aug 14;280(1768):20131541. doi: 10.1098/rspb.2013.1541. Print 2013 Oct 7.
The marine tropics contain five major biogeographic regions (East Pacific, Atlantic, Indian Ocean, Indo-Australian Archipelago (IAA) and Central Pacific). These regions are separated by both hard and soft barriers. Reconstructing ancestral vicariance, we evaluate the extent of temporal concordance in vicariance events across three major barriers (Terminal Tethyan Event (TTE), Isthmus of Panama (IOP), East Pacific Barrier, EPB) and two incomplete barriers (either side of the IAA) for the Labridae, Pomacentridae and Chaetodontidae. We found a marked lack of temporal congruence within and among the three fish families in vicariance events associated with the EPB, TTE and IOP. Vicariance across hard barriers separating the Atlantic and Indo-Pacific (TTE, IOP) is temporally diffuse, with many vicariance events preceding barrier formation. In marked contrast, soft barriers either side of the IAA hotspot support tightly concordant vicariance events (2.5 Myr on Indian Ocean side; 6 Myr on Central Pacific side). Temporal concordance in vicariance points to large-scale temporally restricted gene flow during the Late Miocene and Pliocene. Despite different and often complex histories, both hard and soft barriers have comparably strong effects on the evolution of coral reef taxa.
海洋热带地区包含五个主要的生物地理区域（东太平洋、大西洋、印度洋、印度-澳大利亚群岛（IAA）和中太平洋）。这些区域被硬隔离和软隔离所分隔。通过重建祖先的隔离事件，我们评估了在三个主要隔离事件（终端特提斯事件（TTE）、巴拿马地峡（IOP）、东太平洋隔离事件（EPB））和两个不完整隔离事件（IAA 的两侧）中，裂唇鱼科、雀鲷科和刺盖鱼科之间的时间一致性程度。我们发现，在与 EPB、TTE 和 IOP 相关的隔离事件中，三个鱼类家族内部和之间的时间一致性明显缺乏。硬隔离事件（TTE、IOP）分隔大西洋和印度-太平洋，其隔离时间是扩散的，许多隔离事件发生在隔离事件形成之前。相比之下，IAA 热点两侧的软隔离事件支持紧密一致的隔离事件（印度洋一侧为 2.5 百万年；中太平洋一侧为 6 百万年）。隔离事件的时间一致性表明，在晚中新世和上新世期间，存在大规模的、时间限制的基因流动。尽管存在不同且往往复杂的历史，但硬隔离和软隔离对珊瑚礁分类群的进化都有类似的强烈影响。
