The successive transitional forms presented between the cautious neatness of youth and bold freedom of maturity offer a delightful study.

在青年的谨慎整洁和成熟的大胆自由之间呈现的连续过渡形式提供了令人愉快的研究。

The fossil record is full of transitional forms, like Gobisaurus, that can help us solve evolutionary mysteries like this, if we just think to ask the right questions.

化石记录中充满了过渡形式，例如戈壁龙，如果我们想问正确的问题，它们可以帮助我们解开这样的进化之谜。

The Jebel Irhoud fossils suggest a transitional form, in which humans evolved small faces early or even kept them from an archaic ancestor, and didn’t get the modern braincase until later.

Jebel Irhoud 化石暗示了一种过渡形式，在这种形式中， 人类很早就进化出小脸， 甚至从远古祖先那里保留下来， 直到后来才得到现代脑壳。

However, it's a lot less easy when we take in transitional forms, things like Anchiornis and Archaeopteryx and Sapeornis and then suddenly the lines become very blurry and it's hard to define.

然而，当我们采用过渡形式时，它就不那么容易了，比如近鸟龙、始祖鸟和深鸟龙，然后线条突然变得非常模糊，很难定义。