In the past few thousand years, many populations have evolved genetic adaptations to their local environments.

在过去几千年中，很多人类族群进化出了适应当地环境的基因。

Gradual extinction, in other words, is a natural step in the evolution of life; but no amount of genetic adaptation could prepare living organisms for the catastrophic events to come.

换句话说，逐渐灭绝是生命进化的一个自然步骤；但是，再多的遗传适应也无法使生物体为即将到来的灾难性事件做好准备。

Researchers have also been investigating whether genetic adaptations to a specific environment could appear very quickly through epigenetic modification: changes not to genes themselves, but to whether and when certain genes are expressed.

不是因为基因本身变化，而是根据一些基因是否或何时会被表达。