Whales and dolphins have been found with hind limbs; this rare occurrence is due to the reemergence of a trait they inherited from their terrestrial ancestors.

发现鲸和海豚身上有后肢；这种稀有的现象是由于它们在陆地上的祖先身上的特征再次被遗传。

youdao

It is unusual, however, for whales and dolphins to get stranded together.

这次不同的是，鲸鱼和海豚会同时搁浅。

youdao

Killer whales and dolphins show distinct cultural groups within their populations.

虎鲸和海豚在他们的群落中内有着截然不同的文化族群。

youdao

"They asked me to come with them into this cove in Taiji,Japan where they massacre dolphins and small whales.

VOA: standard.2010.08.04

If we can make homes for whales and dolphins, the ocean may just have a chance.

BBC: Saving the seas for marine mammals

Whales and dolphins have complex cultures, too, which vary from group to group within a species.

ECONOMIST: A declaration of the rights of cetaceans

To help advance the creation of MPAs, we devised the idea of "homes for whales and dolphins".

BBC: Saving the seas for marine mammals