Data from: Molecular clocks indicate turnover and diversification of modern coleoid cephalopods during the Mesozoic Marine Revolution

Coleoid cephalopod molluscs comprise squid, cuttlefish and octopuses, and represent nearly the entire diversity of modern cephalopods. Sophisticated adaptations such as the use of colour for camouflage and communication, jet propulsion and the ink sac highlight the unique nature of the group. Despite these striking adaptations, there are clear parallels in ecology between coleoids and bony fishes. The coleoid fossil record is limited, however, hindering confident analysis of the tempo and pattern of their evolution. Here we use a molecular dataset (180 genes, approx. 36 000 amino acids) of 26 cephalopod species to explore the phylogeny and timing of cephalopod evolution. We show that crown cephalopods diverged in the Silurian–Devonian, while crown coleoids had origins in the latest Palaeozoic. While the deep-sea vampire squid and dumbo octopuses have ancient origins extending to the Early Mesozoic Era, 242 ± 38 Ma, incirrate octopuses and the decabrachian coleoids (10-armed squid) diversified in the Jurassic Period. These divergence estimates highlight the modern diversity of coleoid cephalopods emerging in the Mesozoic Marine Revolution, a period that also witnessed the radiation of most ray-finned fish groups in addition to several other marine vertebrates. This suggests that that the origin of modern cephalopod biodiversity was contingent on ecological competition with marine vertebrates.鞘亚纲头足类软体动物（coleoid cephalopod molluscs）涵盖鱿鱼、乌贼与章鱼，代表了现代头足类几乎全部的物种多样性。诸如利用色彩实现伪装与交流、喷气推进以及墨囊等复杂适应性特征，凸显了该类群的独特性。尽管具备这些引人注目的适应性演化特征，鞘亚纲头足类与硬骨鱼在生态学特征上仍存在明显的相似性。然而，鞘亚纲头足类的化石记录较为匮乏，这阻碍了对其演化速率与演化模式的可靠分析。本研究利用涵盖26个头足类物种的分子数据集（180个基因，约36000个氨基酸残基），探究头足类演化的系统发育关系与时间节点。研究结果显示，冠群头足类（crown cephalopods）的分化发生于志留纪-泥盆纪时期，而冠群鞘亚纲头足类（crown coleoids）起源于晚古生代。虽然深海吸血鬼乌贼（vampire squid）与烟灰蛸（dumbo octopuses）的古老起源可追溯至早中生代（242 ± 38 Ma），但八腕亚目章鱼（incirrate octopuses）与十腕亚目鞘类（decabrachian coleoids，10腕鱿鱼）的物种多样化发生于侏罗纪时期。上述分化时间估算结果表明，鞘亚纲头足类的现代多样性形成于中生代海洋革命（Mesozoic Marine Revolution）时期——这一时期同样见证了绝大多数辐鳍鱼类（ray-finned fish）类群以及其他多种海洋脊椎动物的辐射演化。该研究结果暗示，现代头足类生物多样性的起源与海洋脊椎动物的生态竞争密切相关。