* Sound perception: Dolphins have highly developed hearing abilities. They use echolocation (emitting sounds and interpreting the echoes) to navigate, hunt, and communicate. Their ears are sensitive to a much wider range of frequencies than humans, including sounds far above and below our hearing range.
* Language differences: While dolphins communicate with complex sounds and whistles, their language is fundamentally different from human speech. They don't use the same vocalizations or structures to convey meaning.
* Frequency range: Human voices fall within the frequency range that dolphins can hear, but they are not the ideal frequency for dolphins to process. They may be able to detect human speech, but it's unlikely they would be able to interpret the meaning.
* Context and learning: Dolphins can learn to respond to certain sounds and vocal cues, especially if they are trained in a specific environment. However, their ability to understand human speech in a natural setting is limited.
In summary: Dolphins can hear human voices, but they don't understand them like human speech. They are more attuned to sounds related to echolocation and their own complex communication system.