PubMed
概括

在Astyanax mexicanus中,表面鱼的颜色和眼睛大小的等位基因在洞穴种群中迅速被消除,尽管基因流动. 这表明强烈的选择,而不是漂移,维持了这种物种的洞穴适应.

相关概念视频

Convergent Evolution01:54

Convergent Evolution

Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
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Speciation Rates01:07

Speciation Rates

Overview
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Formation of Species01:31

Formation of Species

Speciation describes the formation of one or more new species from one or sometimes multiple original species. The resulting species are discrete from the parent species, and barriers to reproduction will typically exist. There are two primary mechanisms, speciation with and without geographic isolation—allopatric and sympatric speciation, respectively.
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Osmoregulation in Fishes

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The Evidence for Evolution02:55

The Evidence for Evolution

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Genetics of Speciation02:16

Genetics of Speciation

Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.
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