从化石记录中可以了解到一些已经灭绝、但已经完全变成海洋生物的鲸目动物。

Extinct but already fully marine cetaceans are known from the fossil record.

youdao

从化石记录中可以了解到一些已经灭绝、但已经完全变成海洋生物的鲸目动物。

Extinct but already fully marine cetaceans are known from the fossil record.

youdao