Halanych K M, Demboski J R, van Vuuren B J, Klein D R, Cook J A
Department of Zoology and Entomology, University of Pretoria, Pretoria, 0002, South Africa.
Mol Phylogenet Evol. 1999 Mar;11(2):213-21. doi: 10.1006/mpev.1998.0581.
Jackrabbits and hares, members of the genus Lepus, comprise over half of the species within the family Leporidae (Lagomorpha). Despite their ecological importance, potential economic impact, and worldwide distribution, the evolution of hares and jackrabbits has been poorly studied. We provide an initial phylogenetic framework for jackrabbits and hares so that explicit hypotheses about their evolution can be developed and tested. To this end, we have collected DNA sequence data from a 702-bp region of the mitochondrial cytochrome b gene and reconstructed the evolutionary history (via parsimony, neighbor joining, and maximum likelihood) of 11 species of Lepus, focusing on North American taxa. Due to problems of saturation, induced by multiple substitutions, at synonymous coding positions between the ingroup taxa and the outgroups (Oryctolagus and Sylvilagus), both rooted and unrooted trees were examined. Variation in tree topologies generated by different reconstruction methods was observed in analyses including the outgroups, but not in the analyses of unrooted ingroup networks. Apparently, substitutional saturation hindered the analyses when outgroups were considered. The trees based on the cytochrome b data indicate that the taxonomic status of some species needs to be reassessed and that species of Lepus within North America do not form a monophyletic entity.
长耳大野兔和野兔属于兔属，占兔科（兔形目）物种的一半以上。尽管它们具有重要的生态意义、潜在的经济影响且分布于全球，但对野兔和长耳大野兔的进化研究甚少。我们为长耳大野兔和野兔提供了一个初步的系统发育框架，以便能够提出并检验关于它们进化的明确假设。为此，我们从线粒体细胞色素b基因的一个702碱基对区域收集了DNA序列数据，并重建了11种兔属物种的进化历史（通过简约法、邻接法和最大似然法），重点关注北美类群。由于内类群分类单元与外类群（穴兔属和棉尾兔属）之间同义编码位置上的多次替换导致的饱和问题，我们同时检查了有根树和无根树。在包括外类群的分析中，观察到不同重建方法产生的树形拓扑结构存在差异，但在无根内类群网络分析中未观察到。显然，考虑外类群时，替换饱和阻碍了分析。基于细胞色素b数据的树状图表明，一些物种的分类地位需要重新评估，并且北美兔属的物种并不构成一个单系类群。
