Moritz Craig C, Wright John W, Brown Wesley M
Laboratory of Molecular Systematics, Museum of Zoology, and Department of Biology, University of Michigan, Ann Arbor, MI, 48109-1079.
Section of Herpetology, Natural History Museum of Los Angeles County, Los Angeles, CA, 90007.
Evolution. 1989 Aug;43(5):958-968. doi: 10.1111/j.1558-5646.1989.tb02542.x.
Mitochondrial DNAs (mtDNAs) of two unisexual, parthenogenetically reproducing species of whiptail lizards (Cnemidophorus velox and C. exsanguis) and their bisexual relatives were compared by restriction-enzyme analysis to assess levels of mtDNA variation and to establish the maternal ancestry of the unisexuals. No cleavage-site differences were found to be diagnostic between C. velox and C. exsanguis mtDNAs, suggesting an ancestry rooted in the same maternal lineage. The mtDNA of the unisexuals is relatively homogeneous, indicating that these lineages are of recent origin. Phylogenetic analysis revealed that the maternal ancestor of both C. velox and C. exsanguis was most probably C. burti stictogrammus, C. costatus barrancorum, or an unidentified taxon closely related to them. In addition, the mtDNA analyses demonstrate conclusively that the triploid species C. velox could not have been formed by the fertilization of an unreduced (diploid) C. inornatus egg, further strengthening the hypothesis that parthenogenesis in Cnemidophorus results from hybridization.
通过限制性酶切分析比较了两种单性、孤雌生殖的鞭尾蜥（Cnemidophorus velox和C. exsanguis）及其两性亲属的线粒体DNA（mtDNA），以评估mtDNA的变异水平并确定单性生殖物种的母系祖先。未发现C. velox和C. exsanguis的mtDNA之间存在可用于诊断的酶切位点差异，这表明它们起源于同一母系谱系。单性生殖物种的mtDNA相对同质，表明这些谱系起源较近。系统发育分析表明，C. velox和C. exsanguis的母系祖先很可能是C. burti stictogrammus、C. costatus barrancorum或与其密切相关的未鉴定分类群。此外，mtDNA分析确凿地证明，三倍体物种C. velox不可能由未减数（二倍体）的C. inornatus卵受精形成，这进一步强化了鞭尾蜥孤雌生殖源于杂交的假说。
