Genetic differentiation in Daphnia obtusa: a continental perspective
Genetic differentiation in Daphnia obtusa: a continental perspective
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钝角溞的遗传分化：大陆视角
DOI：
10.1046/j.1365-2427.1996.00501.x
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发表时间：
1996
影响因子：
2.7
通讯作者：
T. Finston
中科院分区：
文献类型：
--
作者：
P. Hebert;T. Finston
1.以前大多数关于达夫类种群遗传多样性的研究规模有限，提供的关于基因频率地理模式的信息有限。本研究通过研究北美暖温带地区分布最广的水蚤种群的等位酶差异来解决这一差距。
2.该物种的地方种群表现出典型的基因频率分化。然而，与分布广泛的其他达夫尼纲动物相比，在更大的地理尺度上，进一步的分化是明显的，北美钝顶丝虫被分成三个谱系，基本上表现出异地分布。这三个谱系主要基于三个多态基因座上的等位基因频率变化，并由东部、中部和西南部群体代表。
3.由于这种分化模式，地理距离和遗传分化之间不存在简单的单调关系。相反，属于特定谱系的局部集合种群在数千公里内几乎没有遗传差异，而在不同谱系接触的地区，基因频率在数百公里以上发生显著变化。
1. The restricted scale of most prior studies of genetic diversity in daphniid populations provides limited information on the geographical patterning of gene frequencies. The present study addresses this gap by examining allozymic divergence in populations of the most broadly distributed daphniid in the warm temperate regions of North America, Daphnia obtusa, across its range.
2. Local populations of this species show the gene frequency differentiation typical of other daphniids. In contrast to other daphniids with broad distributions, however, further divergence is apparent at a larger geographical scale, with North American D. obtusa fragmented into three lineages showing largely allopatric distributions. The three lineages are based primarily on allele frequency shifts at three polymorphic loci and are represented by eastern, central and south-western groupings.
3. Because of this pattern of differentiation, there is no simple monotonic relationship between geographical distance and genetic divergence. Instead, local metapopulations belonging to a specific lineage show little genetic divergence over several thousand km, while marked shifts in gene frequency occur over a few hundred km in regions where different lineages are in contact.