Data from: Diet evolution and clade richness in Hexapoda: a phylogenetic study of higher taxa

Hexapoda, the insects and their relatives, includes over half of all described species. Because large proportions of this diversity cluster within a small set of phytophagous groups, dietary-substrates have been proposed to shape patterns of richness within the clade through antagonistic co-evolution and zones of ecological opportunity. Here we explore these processes in the context of a recent dated phylogeny of Hexapod families. Our results indicate phylogenetic clustering of specialized ecologies such as phytophagy and parasitism, but reveal no consistent associations between the use of particular dietary substrates and clade richness. We also find no evidence that diets expected to promote antagonistic co-evolution are consistently associated with elevated species richness, nor that sister clades differing in dietary state are associated with greater-than-expected differences in richness. We do, however, identify variation in the age of, and transition rates among, dietary states that are likely to play a role in the observed heterogeneity in richness among dietary classes. Based on these findings we suggest remaining circumspect about the generality of adaptive zones based on broad dietary groupings as an explanation for hexapod richness, and suggest that richness heterogeneity may be better explained by origination and transitions rates, and variation within dietary categories.六足动物（Hexapoda）涵盖昆虫及其近缘类群，占所有已描述物种的半数以上。由于该类群的多样性高度集中于少数植食性类群，相关假说认为食性底物可通过拮抗共进化与生态机遇区，塑造该演化支（clade）内的物种丰富度格局。本研究依托近期发表的六足动物科水平定年系统发育树，对上述过程展开探究。研究结果显示，植食性、寄生生活等特化生态位存在系统发育聚集现象，但未发现特定取食底物的使用与演化支丰富度之间存在一致关联；同时，未找到证据表明，理论上可促进拮抗共进化的食性会持续伴随物种丰富度提升，也未发现食性状态存在差异的姐妹演化支（sister clades），其丰富度差值高于预期水平。不过，本研究确证了食性状态的起源年龄与转换速率存在变异，这类变异或可解释不同食性类群间已观测到的丰富度异质性。基于上述发现，我们认为，以宽泛食性类群为基础的适应区（adaptive zone）假说，作为解释六足动物物种丰富度的通用框架仍需审慎；而物种丰富度的异质性，或许可通过起源速率、转换速率以及食性类群内部的变异得到更好的阐释。