Dolphins should be treated as non-human "persons", with their rights to life and liberty respected, scientists meeting in Canada have been told.
Experts in philosophy, conservation and animal behaviour want support for a Declaration of Rights for Cetaceans.
They believe dolphins and whales are sufficiently intelligent to justify the same ethical considerations as humans.
Recognising their rights would mean an end to whaling and their captivity, or their use in entertainment.
"Science has shown that individuality - consciousness, self-awareness - is no longer a unique human property. That poses all kinds of challenges.”
The move was made at the annual meeting of the American Association for the Advancement of Science (AAAS) in Vancouver, Canada, the world's biggest science conference.
It is based on years of research that has shown dolphins and whales have large, complex brains and a human-like level of self-awareness.
This has led the experts to conclude that although non-human, dolphins and whales are "people" in a philosophical sense, which has far-reaching implications.
Ethics expert Prof Tom White, from Loyola Marymount University, Los Angeles, author of In Defence of Dolphins: The New Moral Frontier, said dolphins were "non-human persons".
"A person needs to be an individual. If individuals count, then the deliberate killing of individuals of this sort is ethically the equivalent of deliberately killing a human being.
India has declared dolphins to be non-human persons -