A genetic record of population isolation in pocket gophers during Holocene climatic change
A genetic record of population isolation in pocket gophers during Holocene climatic change
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DOI：
10.1073/pnas.95.12.6893
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发表时间：
1998-06-09
影响因子：
11.1
通讯作者：
Wayne, RK
中科院分区：
文献类型：
--
作者：
Hadly, EA;Kohn, MH;Wayne, RK
第四纪古生物学中一个长期存在的问题是，气候引起的种群水平的表型变化是大规模迁移还是孤立进化的结果。为了直接测量遗传变异随时间的变化，研究人员在怀俄明州黄石国家公园拉马尔洞穴的全新世口袋地鼠（Thomomys talpoides）序列中测量了2400多年来的古代DNA和形态变化。在Lamar洞穴附近收集的古代标本和现代标本都有线粒体细胞色素b序列，而这些序列在邻近地区是不存在的，这表明该种群在整个时期都是孤立的。相比之下，与体型和营养水平相关的形态特征——横轴长度则会随着气候变化而发生可预测的变化。我们的研究结果表明，小型哺乳动物种群可以经历许多微观进化理论模型所假设的长期隔离。
A long-standing question in Quaternary paleontology is whether climate-induced, population-level phenotypic change is a result of large-scale migration or evolution in isolation. To directly measure genetic variation through time, ancient DNA and morphologic variation was measured over 2,400 years in a Holocene sequence of pocket gophers (Thomomys talpoides) from Lamar Cave, Yellowstone National Park, Wyoming. Ancient specimens and modern samples collected near Lamar Cave share mitochondrial cytochrome b sequences that are absent from adjacent localities, suggesting that the population was isolated for the entire period. In contrast, diastemal length, a morphologic character correlated with body size and nutritional level, changed predictably in response to climatic change. Our results demonstrate that small mammal populations can experience the long-term isolation assumed by many theoretical models of microevolutionary change.