Wilkinson G S, Fleming T H
Department of Zoology, University of Maryland, College Park 20742, USA.
Mol Ecol. 1996 Jun;5(3):329-39.
We used sequence variation within 297 bp of control region mitochondrial DNA (mtDNA) amplified from 53 lesser long-nosed bats, Leptonycteris curasoae (Phyllostomidae: Glossophaginae) captured at 13 locations in south-western United States and Mexico and one site in Venezuela to infer population structure and possible migration routes of this endangered nectar- and fruit-eating species. Phylogenetic analysis using maximum parsimony and UPGMA confirmed species and subspecies distinctions within Leptonycteris and revealed two clades exhibiting 3% sequence divergence within the Mexican subspecies, L. c. yerbabuenae. Even though many roots contained L. c. yerbabuenae from both clades, weak population structure was detected both by a correlation between genetic differentiation, F(st), and geographical distance and by a cladistic estimate of the number of migration events required to align bat sequences with geographical location on maximum parsimony, as compared to random, trees. Three results suggest that L. c. yerbabuenae are more likely to migrate between sites along the Pacific coast of Mexico or along the foothills of the Sierra Madre Occidental than between these regions. (1) Seventeen of 20 bats which shared an identical sequence were captured up to 1800 km apart but within the same putative migration corridor. (2) Residuals from a regression of F(st) on distance were greater between than within these regions. (3) Fewer migration events were required to align bats with these two groups than expected from random assignment. We recommend analysing independent genetic data and monitoring bat visitation to roost sites during migration to confirm these postulated movements.
我们利用从53只小长鼻蝠（Leptonycteris curasoae，叶口蝠科：长舌蝠亚科）线粒体DNA（mtDNA）控制区297 bp内扩增出的序列变异来推断该濒危食花蜜和果实物种的种群结构及可能的迁徙路线。这些小长鼻蝠是在美国西南部和墨西哥的13个地点以及委内瑞拉的一个地点捕获的。使用最大简约法和UPGMA进行的系统发育分析证实了长鼻蝠属内的物种和亚种差异，并揭示了墨西哥亚种L. c. yerbabuenae内的两个分支，它们之间的序列差异为3%。尽管许多样本包含来自两个分支的L. c. yerbabuenae，但通过遗传分化（Fst）与地理距离之间的相关性以及通过对将蝙蝠序列与最大简约树上的地理位置对齐所需的迁徙事件数量进行分支估计（与随机树相比），均检测到了较弱的种群结构。三个结果表明，L. c. yerbabuenae更有可能在墨西哥太平洋沿岸或西马德雷山脉山麓的地点之间迁徙，而不是在这些区域之间。（1）20只具有相同序列的蝙蝠中有17只在相距达1800公里但在同一假定迁徙走廊内被捕获。（2）这些区域之间Fst对距离回归的残差大于区域内。（3）将蝙蝠与这两组对齐所需的迁徙事件比随机分配预期的要少。我们建议分析独立的遗传数据，并在迁徙期间监测蝙蝠对栖息地的访问情况，以确认这些假定的迁徙行为。
