Johnson Jeff A, Brown Joseph W, Fuchs Jérôme, Mindell David P
Department of Biological Sciences and Institute of Applied Science, University of North Texas, 1155 Union Circle, Denton, TX 76203, USA.
Department of Ecology & Evolutionary Biology, University of Michigan, 830 North University, Ann Arbor, MI 48109, USA.
Mol Phylogenet Evol. 2016 Dec;105:193-199. doi: 10.1016/j.ympev.2016.08.025. Epub 2016 Sep 4.
New World Vultures are large-bodied carrion feeding birds in the family Cathartidae, currently consisting of seven species from five genera with geographic distributions in North and South America. No study to date has included all cathartid species in a single phylogenetic analysis. In this study, we investigated the phylogenetic relationships among all cathartid species using five nuclear (nuc; 4060bp) and two mitochondrial (mt; 2165bp) DNA loci with fossil calibrated gene tree (27 outgroup taxa) and coalescent-based species tree (2 outgroup taxa) analyses. We also included an additional four nuclear loci (2578bp) for the species tree analysis to explore changes in nodal support values. Although the stem lineage is inferred to have originated ∼69 million years ago (Ma; 74.5-64.9 credible interval), a more recent basal split within Cathartidae was recovered at ∼14Ma (17.1-11.1 credible interval). Two primary clades were identified: (1) Black Vulture (Coragyps atratus) together with the three Cathartes species (Lesser C. burrovianus and Greater C. melambrotus Yellow-headed Vultures, and Turkey Vulture C. aura), and (2) King Vulture (Sarcoramphus papa), California (Gymnogyps californianus) and Andean (Vultur gryphus) Condors. Support for taxon relationships within the two basal clades were inconsistent between analyses with the exception of Black Vulture sister to a monophyletic Cathartes clade. Increased support for a yellow-headed vulture clade was recovered in the species tree analysis using the four additional nuclear loci. Overall, these results are in agreement with cathartid life history (e.g. olfaction ability and behavior) and contrasting habitat affinities among sister taxa with overlapping geographic distributions. More research is needed using additional molecular loci to further resolve the phylogenetic relationships within the two basal cathartid clades, as speciation appeared to have occurred in a relatively short period of time.
新大陆兀鹰是新域鹫科中以腐肉为食的大型鸟类，目前包括来自五个属的七个物种，分布于北美洲和南美洲。迄今为止，尚无研究在单一系统发育分析中纳入所有新域鹫科物种。在本研究中，我们使用五个核基因（nuc；4060bp）和两个线粒体基因（mt；2165bp）位点，通过化石校准基因树（27个外类群分类单元）和基于溯祖的物种树（2个外类群分类单元）分析，研究了所有新域鹫科物种之间的系统发育关系。我们还在物种树分析中纳入了另外四个核基因位点（2578bp），以探讨节点支持值的变化。尽管推断其干群谱系起源于约6900万年前（Ma；可信区间为7450 - 6490万年前），但新域鹫科内更近的一次基部类群分裂出现在约1400万年前（可信区间为1710 - 1110万年前）。识别出两个主要分支：（1）黑兀鹰（Coragyps atratus）与新域鹫属的三个物种（小黄头新域鹫Cathartes burrovianus、大黄头新域鹫C. melambrotus和红头美洲鹫C. aura），以及（2）王鹫（Sarcoramphus papa）、加州神鹫（Gymnogyps californianus）和安第斯神鹫（Vultur gryphus）。除了黑兀鹰作为单系新域鹫属分支的姐妹群外，两种分析方法对两个基部类群内分类单元关系的支持并不一致。在使用另外四个核基因位点进行的物种树分析中，对黄头新域鹫分支的支持度有所增加。总体而言，这些结果与新域鹫科的生活史（如嗅觉能力和行为）以及姐妹分类单元之间重叠地理分布的不同栖息地亲和力一致。由于物种形成似乎发生在相对较短的时间内，因此需要使用更多分子位点进行更多研究，以进一步解析两个基部新域鹫科类群内的系统发育关系。
