Are Dolphins Also Persons?

Scientists who have studied the remarkable lives of dolphins have found themselves in a bit of an ethical quagmire.

There seems to be little doubt now that dolphins are surprisingly intelligent, know who they are as individuals, and engage in cultural traditions that can be passed on to succeeding generations. In short, they are a lot like humans.

So, should they be treated as "persons"? Should they be recognized as fellow travelers on this planet, rather than captive exhibitionists or laboratory specimens?

Leaders in the field held a standing-room-only symposium last Sunday in San Diego during the annual convention of the American Association for the Advancement of Science, and they got an earful.

VIDEO: Dolphins Blow Bubble Rings UnderwaterPlay

"The response was very much divided," Lori Marino, a neuroscientist and animal behaviorist at Emory University said in a telephone interview. Marino was a co-investigator in a convincing experiment that showed in 2001 how dolphins are incredibly self-aware, returning to a mirror over and over again to check out their bodies.

Determining animal intelligence is a thorny problem, even if the animals are somewhat like ourselves. But it's especially difficult if the animals are very different from us, and live in a world that is unlike ours, but clearly have active minds.

Some Say Dolphins Should Be Considered 'Non-Human Persons'

Do other animals ponder the stars and wonder about the universe? Probably not. But research shows that dolphins can at least think about the future.


Findings like that have led some distinguished scientists and ethicists to suggest we need to rethink our role as humans. It turns out we are not alone, and we didn't need to journey into space to find out.

Thomas I. White of the Oxford Centre for Animal Ethics and Loyola Marymount University in Los Angeles told the AAAS session that dolphins should be regarded as "non-human persons," a phrase that has caught on among some scientists.

"Like humans, dolphins appear to be self-conscious, unique individuals with distinctive personalities, memories and a sense of self, who are vulnerable to a wide range of physical and emotional pain and harm, and who have the power to reflect upon and choose their actions," White told an audience that lingered long after the session had ended because participants wanted to discuss the issue further.

VIDEO: Scientists film dolphins using their tails to toss jellyfish.Play

What If Dolphins Were Given 'Person' Status?

Giving "person" status to another creature could embolden radical animal protectionists, thus complicating the lives of scientists who depend on a wide range of animals for laboratory research.

But the evidence that some animals are more like us than we might want to believe is so compelling that Marino, one of the leaders in dolphin research, vowed in the telephone interview that she would now study only dolphins in nature, not captivity.

That's significant, because Marino and a colleague, Diana Reiss, successfully carried out one of the most compelling experiments in the relatively brief history of research into intelligence among marine animals.

Marino's grad school adviser at the State University of New York at Albany, Gordon Gallup, is the scientist who first used a mirror to show that chimps recognize themselves, a major breakthrough in the search for other animals with self-awareness. Intrigued with that work, Marino wanted to expand into some area other than heavily researched primates.

Dolphins Are Self-Aware, Research Indicates

Marino began researching dolphins and determined that they had a brain-to-body-mass ratio that is second only to humans. Human beings have the largest brains, compared to their body mass, of any known animals. Brain size, relative to body size, is believed by many scientists to be a key prerequisite to intelligence, although there are many other factors as well.

So Marino and Reiss turned to the New York Aquarium, which had a couple of male bottlenose dolphins in captivity, to see if they knew who they were.

"We marked them on different parts of their bodies with a magic marker," Marino said. Each dolphin immediately raced to the mirror, "postured in front of the mirror and positioned itself in strange ways to expose the marked part of its body much the same way that you and I would if we passed a wall with wet paint on it. As soon as we get to the bathroom we would look in the mirror and turn around to see if we got any paint on us."

Sometimes the researchers used a marker that left no mark, and the result was quite different. The dolphin would dash to the mirror, but if he could not find a mark, he would immediately move on, ignoring the incident. Marino and other researchers have concluded that the experiment showed the dolphins were aware of who they were and knew it was their body they were checking out.

Dolphins, Whales, Primates Can Follow Certain Rules

"That's a very rare capacity in the non-human animal kingdom," Marino said.

Other researchers have found that dolphins also know how to observe and perpetrate their own traditions. A number of animals, especially whales and dolphins and primates, know how to follow certain rules.

Dolphins, like humpback whales, are known to engage in bubble feeding, a complex system in which some members of the pod create a cage of bubbles to give the prey the sense of being captive. Then, other members charge in and dine effortlessly.

"That's a great example of cultural tradition," Marino said. Not all whales, for example, engage in bubble feeding. "It's something that a specific group does, and they pass it along to the next generation through learning," she added.

So what does it all mean?

"It means that as human beings, we are not alone in being the kind of animals that reflect upon ourselves and put into perspective who we are," Marino said. So our world has, relatively recently, become much more complicated.

And despite the fact that about 300,000 dolphins, whales and porpoises die every year as unintentional victims of fishermen's nets, and some end up in captivity for our amusement, they still seem to like us.

Dolphins Sometimes Protect Humans

Marino said she has looked into reports that dolphins have shielded some humans from sharks, and she has become a believer. Many of the reports, she said, have been corroborated.

"It's not much of a stretch," she noted. "The behavior they use to protect people when people are in danger are very much the same behavior they use to protect their juveniles."

They form a circle around the swimmer, slap the water with their tails and create a barrier between the humans and the shark, she said. And that's just what they do to protect their own.

But not always. Sometimes dolphins look the other way when a shark cruises toward humans. And considering how we sometimes behave, who could blame them?

After all, aren't they persons, too?