He and his colleagues genotyped more than 8000 fish to find out how the frequency of different versions of the gene, or alleles, changed in the two populations between 1994 and 2003.

他和同事测定了8000多条鳕鱼的基因型，研究两个鱼群中不同版本的基因，或者说等位基因的频率在1994年至2003年间是如何变化的。

youdao

So it's centered at this frequency that was expected, but it's actually split into two different frequencies.

它的中心在预计频率处，但劈裂成两个不同频率。

youdao

With ordinary photocells, one can pick up the frequency between two different lasers.

用普通光电池，人们就能够探测到两个不同的激光之间的拍频。

youdao

So it's centered at this frequency that was expected, but it's actually split into two different frequencies.

它的中心在预计频率处，但劈裂成两个不同频率。

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