If these silent genes are somehow switched back on, they argued, long-lost traits could reappear.

他们认为如果这些不活动基因重新活跃起来，丢失已久的特征就会重新出现。

Silent genes accumulate random mutations, they reasoned, eventually rendering them useless.

他们推论不活动基因不断随机突变，最终致使它们变得没有用。

But if silent genes degrade within 6 to 10 million years, how can long-lost traits be reactivated over longer timescales?

但是如果不活动基因在 600~1000 年间退化，这些久失的特征又如何在更长的时间尺度内被重新激活呢？

More recently, however, examples have been reported that break the time limit, suggesting that silent genes may not be the whole story.

然而，最近有一些打破了这个时间限制的例子被报道，表明不活动基因可能不是唯一的因素。

The team calculated that there is a good chance of silent genes surviving for up to 6 million years in e a few individuals in a population, and that some might survive as long as 10 million years.

所以如果一个基因不再被使用，它能在一个物种中存活多久呢？这个团队计算出不活动基因极有可能在一个种群的部分个体中存活长达 600 万年之久，并且有些不活动基因甚至能存活长达千万年之久。