He proposed that biological species change over time by gaining traits that help them survive and reproduce.

他提出，随着时间的推移，生物物种会通过获得有助于它们生存和繁殖的特征而发生变化。

Palaeogenomics is the study of the genomes of ancient, often extinct, biological species.

古基因组学是对古代（通常已灭绝）生物物种的基因组的研究。

This brings us to another way of defining a species; namely, the biological species concept.

这给我们带来了另一种定义物种的方法；即生物物种概念。

Think about what the biological species definition implies.

想想生物物种定义意味着什么。

The biological species concept defines a species as the group of organisms which can interbreed.

生物物种概念将物种定义为可以杂交的生物群。

The biological species concept makes sure that cryptic species, those that look similar but do not interbreed, are separated.

生物物种概念确保将那些看起来相似但不杂交的隐匿物种分开。

However, although biological species definition is relatively simple, in practice, it can be incredibly difficult to apply, particularly to extinct species.

然而，尽管生物物种的定义相对简单，但在实践中却很难应用，尤其是对已灭绝的物种。

All around us, we see examples of biological species that have evolved smart adaptations that enable them to thrive in a given environment.

在我们周围，我们看到了生物物种的例子，这些生物物种已经进化出智能适应能力，使它们能够在特定环境中茁壮成长。

Studying more different biological species, both vocal learners and nonvocal learners, will help us understand which evolutionary pressures cause babbling to be present in some species and not in others.”

研究更多不同的生物物种——无论是发声学习者还是非发声学习者——都有助于我们理解哪些进化压力让一些物种出现了咿呀声，而另一些却没有。”