However, plasmids often contain genes that confer a selective advantage to the bacterium such as resistance to antibiotics.

不过质粒通常包含赋予细菌选择性优势的基因，例如抗生素耐药性。

Is this an adaptation for some selective advantage or is it an accident?

这是出于某种选择性优势的适应还是偶然？

But these traits are only likely to persist if they have some selective advantage, so don't expect a mutant like school-for-the-gifted any time soon.

但这些特征只有在具有一定的选择性优势时才有可能持续存在——所以不要指望像”天才学校“这样的令人害怕的东西会很快出现。

One possibility is that eukaryotes that make more-modern sterols gained a selective advantage between one billion and 800 million years ago, eventually displacing their protosterol-making counterparts.

可能的一种可能性是，在10亿到8亿年前，制造现代固醇的真核生物获得了选择性优势，最终取代了它们制造原始固醇的同类。

This selective advantage led to cells sticking together in a coordinated manner even after dividing, and these cells eventually began exchanging genetic material, AKA, they had sex.

这种选择优势导致细胞在分裂后仍然以一种协调的方式聚在一起，这些细胞最终开始交换遗传物质，也就是它们之间发生了性关系。

In one of these eggs, there was a mutation causing a slight change and selective advantage and this was ultimately the first chicken which then went on to lay chicken eggs.

其中一颗蛋产生基因变化，造成些微转变和选择优势，而这最后变成了第一只鸡，而后它产下了鸡蛋。

The cytoplasm contains ribosomes which are the site of protein synthesis, the nucleoid which contains the genetic material, and plasmids which contain genes that confer a selective advantage to the bacterium.

细胞质中含有核糖体，它们是蛋白质合成的部位；拟核含有遗传物质以及质粒；质粒含有赋予细菌选择性优势的基因。

The brown color variant is the genetically dominant form of plumage in this species, but historically, the recessive pale gray variant triumphed because of its selective advantage in helping these predators blend in.

这种棕色变异是这种物种的显性性状，但历史上，是浅灰色隐性性状占了上风因为这些有选择性的特殊的优势，这些捕食者得以融入环境。