Many animals can learn to understand human language, and some even learn to speak it. Studies involving primates, dolphins, and domesticated animals confirm what any dog owner already knows: No matter what language we speak, the animals we interact with know the meaning of some of our words.
The average dog knows 165 human words, and smart ones can more than 250 words — about the same as a two-year-old human. An elephant named Koshik learned to imitate six words of human speech — in Korean — and use them to communicate with his trainers. Seals and sea lions in captivity learn to understand several human words, and some learn to speak it, including a harbor seal named Hoover who was raised in a Maine household and learned to say, “Hello there!” and “Hey! Hey! Come over here!” in a New England accent.