Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India.
Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India.
Mol Phylogenet Evol. 2019 Oct;139:106560. doi: 10.1016/j.ympev.2019.106560. Epub 2019 Jul 16.
Evolutionary relationships between members of the Antilopina taxon have been much debated in recent years. The 'true antelope' clade is currently comprised of 4 genera viz., Gazella, Nanger, Eudorcas and the monotypic genus Antilope, that includes A. cervicapra. Most studies have focused on the mitochondrial genome or morphological data to study their relationships. However, signals from mitochondrial data can often be misleading when compared with nuclear markers, as has been shown in multiple taxonomic groups. In this study, we revisit the phylogenetic relationships among members of Antilopina, particularly the phylogenetic position of A. cervicapra, using 12 nuclear markers and compare it with the mitochondrial tree. Furthermore, we explore the implications of the results of this study on the taxonomy and biogeography of Indian antelopes. The nuclear phylogenetic trees built using multiple coalescent and concatenated methods all supported a paraphyletic genus Gazella. Antilope was nested within Gazella as opposed to being sister to it, which was suggested by previous studies and our results based on mitochondrial markers. Our fossil-calibrated larger bovid phylogeny, based on nuclear markers, suggested that the Antilope lineage diverged from its sister species more recently in the Pleistocene, rather than in late Miocene as per previous studies. Our biogeographic analyses suggest that the lineage leading to genus Antilope dispersed into India from the Saharo-Arabian realm around 2 mya, post the expansion of grasslands. We speculate that the adaptations of this savanna-grassland specialist did not allow them to extend their range beyond the Indian subcontinent. Whereas, the only other true antelope in India, G. bennetti, extended its range into India more recently, probably after the establishment of the Thar desert in northwest India.
近年来,人们对 Antilopina 分类群成员之间的进化关系进行了大量讨论。“真正的羚羊”分支目前由 4 个属组成,即瞪羚属、旋角羚属、水羚属和单型属羚羊属,其中包括羚羊属 Cervicapra。大多数研究集中在研究它们的关系的线粒体基因组或形态数据上。然而,与核标记相比,线粒体数据的信号往往具有误导性,这在多个分类群中已经得到证明。在这项研究中,我们使用 12 个核标记重新研究了 Antilopina 成员之间的系统发育关系,特别是羚羊属 Cervicapra 的系统发育位置,并将其与线粒体树进行比较。此外,我们探讨了这项研究的结果对印度羚羊分类和生物地理学的影响。使用多种聚合法和串联法构建的核系统发育树都支持羚羊属的并系发生。羚羊属嵌套在 Gazella 内,而不是与其姐妹关系,这与以前的研究和我们基于线粒体标记的结果相反。我们基于核标记构建的化石校准的大型反刍动物系统发育树表明,羚羊属的谱系在更新世与姐妹种的分化时间较近,而不是以前研究中推测的中新世晚期。我们的生物地理学分析表明,导致羚羊属的谱系在大约 200 万年前,在草原扩张之后,从撒哈拉-阿拉伯地区扩散到印度。我们推测,这种草原-草地专家的适应能力不允许它们的范围超出印度次大陆。而印度唯一的另一种真正的羚羊,G. bennetti,最近才扩展到印度,可能是在印度西北部的塔尔沙漠形成之后。