Data from: Extreme dentition does not prevent diet and tooth diversification within combtooth blennies (Ovalentaria: Blenniidae)

The dentition of fishes can be quite striking and is often correlated with a specific diet. Combtooth blennies have long incisiform oral teeth, unlike most actinopterygians. It has been suggested that the long tooth morphology is an adaptation for detritivory, but given the diversity of diets (detritus, coral polyps, polychaetes, and pieces of other fishes), are blenny teeth indeed monomorphic? Or does tooth variation associated with diet still exist at this extreme? To explore tooth and diet diversification, we used a new phylogenetic hypothesis of Blenniidae, measured tooth shape, number, and mode of attachment, and quantified blenniid diet. The ancestral diet of blennies contained detritus and diversified into many different diets, including almost exclusively detritivory. Our results reveal a dental cline that may be constrained by tooth shape, but has not prevented diet diversification. Ancestral state reconstruction of tooth morphologies suggests that the ancestor of blennies had many unattached teeth and featured transitions to fewer attached teeth, with several transitions back to attached or unattached teeth. The dentition of blenniids is not monotypic; rather it is diverse and small changes in tooth shape are accompanied by changes in size, number, attachment, and often diet.鱼类的齿列往往极具特征，且常与特定食性紧密关联。与多数辐鳍鱼类（Actinopterygii）不同，梳齿鳚（Combtooth blennies）拥有修长的门齿型口腔齿。此前有研究推测，这种修长的齿形是对碎屑食性的适应性演化，但鉴于该类群食性的多样性——涵盖碎屑、珊瑚息肉、多毛类环节动物乃至其他鱼类的组织碎片——梳齿鳚的齿列果真均一单型吗？抑或是在这种极端齿形的基础上，仍存在与食性相关的齿列变异？ 为探究齿列与食性的演化分化机制，本研究采用了全新的鳚科（Blenniidae）系统发育假设，量化测定了齿形、齿数及附着模式，并对鳚科鱼类的食性进行了标准化分析。结果显示，鳚科鱼类的祖先食性包含碎屑食性，随后分化出多种食性策略，其中不乏完全专性碎屑食性的类群。本研究揭示了一条可能受齿形约束的齿列渐变群，但该约束并未阻碍食性的多样化演化。对齿形的祖先状态重建结果表明，鳚科鱼类的祖先拥有大量游离齿，其后经历了向附着齿类型的演化转变，且其间存在多次附着齿与游离齿类型之间的可逆转换事件。 综上，鳚科鱼类的齿列并非单型结构，而是具有丰富的多样性；齿形的细微变化往往伴随齿大小、齿数、附着模式的改变，且通常与食性的变化相伴随。