Data from: The herbivorous fish family Kyphosidae (Teleostei: Perciformes) represents a recent radiation from higher latitudes

Aim: Herbivorous reef fishes are considered to have difficulty digesting plant material at extratropical temperatures, and are thus largely restricted to tropical waters where they are thought to have evolved. However, the herbivorous Kyphosidae, with both temperate and tropical species, provides an ideal opportunity to test this view. Previous studies have resolved the taxonomy and distribution patterns of all species. Here, we use a calibrated phylogeny to analyse the age, geographical origin and pattern of diversification of kyphosids to determine their origins in space and time, and thus refine hypotheses on the evolutionary origins of herbivory in reef fishes. Location: Pacific Ocean, Atlantic Ocean, Indian Ocean, Western Australia. Methods: The age and geographic origin of Kyphosidae were determined by incorporating fossil calibrations and species distributions onto a phylogeny of all extant species based on fragments from mitochondrial markers and three nuclear markers, and using Bayesian modelling to reconstruct ancestral distributions. Evolution of both diet and tooth shape were also examined using Bayesian ancestral reconstruction. Results: Ancestral reconstruction suggested a subtropical, southern hemisphere Indo-Pacific origin for the family. The chronogram indicates that Kyphosus originated in the early Miocene, and that tropical diversity reflects very recent diversification. Main conclusions: Contrary to the general perception that herbivorous reef fishes invaded high latitudes from the tropics, herbivorous kyphosids evolved at intermediate latitudes in the southern hemisphere and subsequently diversified into low latitudes where several species dispersed recently to achieve circumglobal distributions. The southern temperate/subtropical reef environment appears to have generated episodes of diversification in several, well-established, widespread reef fish taxa. Some of these reef fish taxa have remained restricted to southern temperate reef environments despite a long tenure in the Cenozoic (e.g. odacines and aplodactylids), and some such as the kyphosids which diversified very recently in both hemispheres resulting in both regional endemics and species with worldwide distributions.研究目的：以往观点认为，草食性礁区鱼类难以在非热带水温下消化植物性物质，因此其分布大多局限于它们被认为演化起源的热带水域。然而，同时拥有温带和热带物种的草食性舵鱼科（Kyphosidae）为验证这一观点提供了理想的研究对象。此前的研究已明确该科所有物种的分类学地位与分布格局。本研究借助校准后的系统发育树，分析舵鱼科的起源时间、地理起源以及多样化模式，以明确其时空起源，进而完善关于礁区鱼类草食性演化起源的相关假说。 研究区域：太平洋、大西洋、印度洋、西澳大利亚海域。 研究方法：本研究基于所有现存舵鱼科物种的线粒体标记（mitochondrial markers）片段与3个核标记（nuclear markers）序列构建系统发育树，结合化石校准点与物种分布数据，通过贝叶斯模型（Bayesian modelling）重建祖先分布区，以此确定舵鱼科的起源时间与地理起源。同时，本研究还利用贝叶斯祖先性状重建法，分析了该科食性与牙齿形态的演化历程。 研究结果：祖先性状重建结果显示，舵鱼科的祖先起源于南半球亚热带印度洋-太平洋海域。时间校准系统树（chronogram）显示，舵鱼属（Kyphosus）起源于中新世早期，而其热带类群的多样性分化发生在非常晚近的时期。 主要结论：与普遍认为的“草食性礁区鱼类从热带水域入侵高纬度海域”的观点相悖，草食性舵鱼科实则起源于南半球的中纬度海域，随后扩散至低纬度水域，其中多个类群在晚近时期通过扩散实现了环全球分布。南半球温带/亚热带礁区环境似乎推动了多个广布性知名礁区鱼类类群的多轮多样化事件。其中部分类群即便在新生代（Cenozoic）存续了漫长的地质时期，仍局限于南半球温带礁区（例如草隆头鱼科（odacines）与唇指鲈科（aplodactylids））；而另一部分类群如舵鱼科，则在南北半球均发生了晚近的多样化事件，既形成了区域特有种，也产生了具有全球分布范围的物种。