【英语时差8,16】M&M巧克力豆与遗传漂变（下）

Every time an animal mates, its offspring receives a mixed bag of genes², half from its mother and half from its father. If the father and the mother share many of the same genes, their offspring will receive doubles of some of them. The doubles don’t help, and they mean that some other gene¹ that could have been passed on wasn’t. Think of the M&Ms. At the point where you failed to pull a red out of the bag, you have lost one gene. If your mate doesn’t have that gene either, then your descendants will never have it. Low populations of animals means less genetic³ variation, which means genetic drift is more likely. If the gene that gets lost was critical to the survival of the species, they might begin dying off altogether.

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

3 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。