Data from: Evolutionary history and biogeographical patterns of barnacles endemic to deep-sea hydrothermal vents

The characterization of evolutionary and biogeographical patterns is of fundamental importance to identify factors driving biodiversity. Due to their widespread but discontinuous distribution, deep-sea hydrothermal vent barnacles represent an excellent model for testing biogeographic hypotheses regarding the origin, dispersal, and diversity of modern vent fauna. Here we characterize the global genetic diversity of vent barnacles to infer their time of radiation, place of origin, mode of dispersal, and diversification. Our approach was to target a suite of multiple loci in samples representing seven out of the eight described genera. We also performed restriction-site associated DNA sequencing on individuals from each species. Phylogenetic inferences and topology hypothesis tests indicate that vent barnacles have colonized deep-sea hydrothermal vents at least twice in history. Consistent with preliminary estimates, we find a likely radiation of barnacles in vent ecosystems during the Cenozoic. Our analyses suggest that the western Pacific was the place of origin of the major vent barnacle lineage, followed by circumglobal colonization eastward through the southern hemisphere during the Neogene. The inferred time of radiation rejects classic hypotheses of antiquity of vent taxa. The timing and the mode of origin, radiation and dispersal are consistent with recent inferences made for other deep-sea taxa, including non-vent species, and are correlated with the occurrence of major geological events and mass extinctions. Thus, we suggest that the geological processes and dispersal mechanisms discussed here can explain current distribution patterns of many other marine taxa and have played an important role shaping deep-sea faunal diversity. These results also constitute critical baseline data with which to assess potential effects of anthropogenic disturbances on deep-sea ecosystems.

阐明演化与生物地理格局，对识别驱动生物多样性形成的关键因素具有根本重要性。深海热液喷口藤壶（deep-sea hydrothermal vent barnacles）分布广泛却不连续，是检验现代喷口动物群起源、扩散与多样性相关生物地理假说的理想模型。本研究旨在解析喷口藤壶的全球遗传多样性，以推断其辐射演化时间、起源地、扩散模式与多样化历程。我们的研究方案为：在覆盖已正式描述的8个属中7个属的样本中靶向扩增多基因座组合；同时对每个物种的个体开展限制性酶切位点相关DNA测序（restriction-site associated DNA sequencing）。系统发育推断与拓扑结构假说检验结果显示，喷口藤壶在历史上至少两次殖民深海热液喷口生态系统。与前期估算结果一致，我们发现新生代时期喷口生态系统中的藤壶曾发生辐射演化。分析结果表明，西太平洋是主要喷口藤壶演化支的起源地，随后在新近纪时期通过南半球向东完成全球范围的殖民扩散。本研究推断的辐射演化时间，推翻了喷口类群起源古老的经典假说。其起源、辐射演化与扩散的时间与模式，与其他深海类群（包括非喷口物种）的近期研究结果相符，且与重大地质事件及集群灭绝事件的发生存在关联。据此我们提出，本文所讨论的地质过程与扩散机制，可解释诸多其他海洋类群的当前分布格局，并在塑造深海动物群多样性方面发挥了重要作用。本研究结果同时可为评估人为干扰对深海生态系统的潜在影响提供关键基准数据。