And this may have happened more than once in the late Proterozoic.

而这 在晚代可能不止一次发生过。

Nuna existed from 1.8 to 1.4 billion years ago, in the middle of the Proterozoic Eon.

努纳存在于 1.8 到 14 亿 年前，在代纪中期。

Scientists believe this early time in motility may have faced a setback soon after the Paleoproterozoic Era, about the time of the Gabon fossils.

科学家，这种早期的动性可能在代（大约是加蓬化石年代）后不久就开始发生倒退。

Primitive ungulates survived and grew after the K-Pg Extinction thanks  to evolutionary innovations like specialized teeth for chewing and grinding vegetation.

原始有蹄类动物在卡罗来纳-代灭绝之后幸存下来并繁衍，这要归功于诸如用于咀嚼和磨碎植物的专门牙齿等进化创新。