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Insects Donate DNA¹ to Unrelated Bugs² 昆虫捐献DNA给无关的虫类

You can thank your parents for your DNA. Because humans share genes³ through sexual reproduction, passing DNA from parent to child. It's known as the 'vertical⁴ transfer' of DNA. Now imagine if you could share just one or two bits of your DNA with an unrelated stranger, through a handshake, or other incidental contact—and that stranger inserted your DNA into their genome.

你要感谢你的父母给你的DNA。因为人类通过有性繁殖分享基因，把DNA从父母传给孩子。它被称为DNA的“垂直转移”。现在想象一下，如果你能与一个不相关的陌生人分享一个或两个你的DNA，仅通过握手、或其他偶然接触，就能使陌生人把你的DNA到加入到他们的基因组中。

No sex. No offspring either. That's called the 'horizontal transfer' of DNA. It's obviously not how humans do it. But it's a mainstay of single-celled organisms like bacteria, which use the process to share antibiotic⁵ resistance genes, for example. And now French scientists have found that horizontal DNA transfer could be a lot more common than we thought in multicellular organisms, too—insects, in this case. Because by analyzing⁶ 195 insect genomes, they found more than 2,200 cases of horizontal DNA transfer between unrelated species of flies and butterflies, beetles⁷ and wasps⁸.

没有性别，也没有后代。这就是所谓的DNA 的“水平转移”。很明显，人类并不是这么做的。但它是单细胞生物如细菌的主要方式，在使用过程中分享抗生素抗性基因，例如，现在法国科学家发现，在多细胞生物中，水平基因转移可能比我们想象的更常见。很多昆虫也是采用这种方式，通过对195个昆虫基因组的分析，他们发现了超过2200例无亲缘关系的苍蝇和蝴蝶、甲虫和黄蜂之间的水平DNA转移。

That total quadruples the number of horizontal DNA transfers previously⁹ described in all animals, plants and fungi¹⁰. The study is in the Proceedings¹¹ of the National Academy of Sciences.

水平DNA转移数量总共4倍于先前描述到的所有动物,植物和真菌。这项研究结果发表在《美国国家科学院院刊》上。

How exactly this genetic¹² transfer happens is still a mystery. Might be viruses, or parasites¹³, doing the DNA delivery. But whatever the cause, it suggests that the evolution of insects, on a molecular¹⁴ level at least, may be something more of a shared success story.

这种基因转移究竟是如何发生的仍是个谜。或许是病毒或寄生虫做的DNA传递。但不管是什么原因，它表明，昆虫的进化，至少在分子水平上，可能是一个共享成功的故事。