Darwin glumly suspected that certain physical and mental frailties among his children arose from a lack of diversity in his family tree.

他怀疑出现在他孩子身上的某些生理和精神方面的问题，一定是由于近亲结婚所致。

The only downside to living in this way is that you'd have to reproduce with your cousin or aunt whichever you prefer really.

生存的唯一劣势是需要近亲结婚。

Marriage between cousins is common in Pakistan, and such inbreeding leads to a high incidence of genetic disorders.

近亲结婚在巴基斯坦很普遍，而种近亲交配引发遗传性疾病的发病率很高。

But inbreeding was a big problem on the island and the population is dying out.

但在个岛上，近亲结婚是个大问题，口也正在衰减。

And their intermarrying has made them different from other folks around here.

而且他们的近亲结婚已经使他们变得跟一带其他的不一了。

It was whispered in Vienna that the heir was clinically insane, that his family's inbreeding had caught up with him.

维也纳有传言说，位继承被诊断为精神失常，他的家族近亲结婚害了他。

The Wilkes are fine folks in their way, and you know I'm fond of them all, but be frank! They are overbred and inbred too, aren't they?

威尔克斯家就他们为来说都是些好，而且你也知道我很喜欢他们，可是让我们坦白说吧！他们吠讲究教养，也太爱搞近亲结婚了。

Throughout history, royals across the world were notorious for incest.

纵观，世界各地的皇室都以近亲结婚而臭名昭著。

All that said, we can't blame every Habsburg death on incest.

话说回来，我们不能把哈布斯堡家族的每一次死亡都归咎于近亲结婚。

Have you ever wondered how inbred the Habsburgs really were?

你有没有想过哈布斯堡家族真的有多近亲结婚？

Despite their parents being closely related, William and his siblings were all born relatively healthy and without any disabilities or deformities, but they were all probably fairly small owing to the size of their mother.

尽管他们的父母是近亲结婚，威廉和他的兄弟姐妹们都相对健康地出生了， 没有残疾或畸形，但他们可能都相当矮小， 因为他们的母亲个子不高。

As these mutations are extremely rare, they tend only to appear in consanguineous relationships where close families intermarry.

由于些突变极为罕见，它们通常只出现在近亲结婚的家庭中。