Yes, they are marine mammals that never come on land. Not to hide, not to have their babies, never!



Do dolphins live their whole life in the ocean?

CONTINUE
How are dolphins adapted for life in the sea?

DIVE DEEPER
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about this topic.

About 45 million years ago, after dinosaurs disappeared from the earth, some mammals left the land to live in the ocean. These evolved into whales, dolphins, and porpoises. Scientists know this from studying fossils.

DOLPHINS
Fossils like this help scientists understand how
dolphins evolved over time.