Dolphin cognitive abilities raise ethical questions, says Emory neuroscientist

February 18, 2010, Emory University
Dolphin cognitive abilities raise ethical questions, says Emory neuroscientist
Two bottlenose dolphins playing with a bubble ring they just created. Photo by Brenda McCowan.

Many modern dolphin brains are significantly larger than those of humans and second in mass to the human brain when corrected for body size, says an Emory scientist. Some dolphin brains exhibit features correlated with complex intelligence, including a large expanse of neocortical volume that is more convoluted than that of humans, extensive insular and cingulated regions, and highly differentiated cellular regions. This has ethical and policy considerations.

Emory University neuroscientist Lori Marino will speak on the anatomical basis of dolphin at the American Association for the Advancement of Science conference (AAAS) in San Diego, on Sunday, Feb. 21.

"Many modern dolphin brains are significantly larger than our own and second in mass to the human when corrected for body size," Marino says.

A leading expert in the neuroanatomy of dolphins and whales, Marino will appear as part of a panel discussing these findings and their ethical and policy implications.

Some dolphin brains exhibit features correlated with complex intelligence, she says, including a large expanse of neocortical volume that is more convoluted than our own, extensive insular and cingulated regions, and highly differentiated cellular regions.

"Dolphins are sophisticated, self-aware, highly intelligent beings with individual personalities, autonomy and an inner life. They are vulnerable to tremendous suffering and ," Marino says.

The growing industry of capturing and confining dolphins to perform in marine parks or to swim with tourists at resorts needs to be reconsidered, she says.

"Our current knowledge of dolphin brain complexity and intelligence suggests that these practices are potentially psychologically harmful to dolphins and present a misinformed picture of their natural intellectual capacities," Marino says.

Marino worked on a 2001 study that showed that can recognize themselves in a mirror - a finding that indicates self-awareness similar to that seen in higher primates and elephants.

Explore further: Scientists say dolphins should be treated as non-human persons

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1.7 / 5 (6) Feb 18, 2010
Oh brother, not Marino again. Still trying to show that Dolphin's are humans? Please...

The simple fact is they are able to be trained. They are also done so through incentive and reward, not punishment. Firstly, it seems unlikely they are suffering, seeing as they are kept safe and plenty fat.

Secondly, while their intelligence is certainly surprising, it is no better than that of a primate. It is certainly not up to the level of a human. Moreover, brain size tells us nothing. When measured, pound for pound, the common shrew has the largest brain to body ratio. Surely, it's not the smartest animal alive...

Marino has a long history of producing research that makes strenuous and questionable inferences.
not rated yet Feb 19, 2010
an odd factoid; in the early sixties John C. Lilly(the pioneer of cetacean science/interspecies communication, owhile observing a group of captive dolphins, he noticed one that was exhibiting antisocial behaviors and not behaving like the others he got the wild idea of injecting 1000 mics of pure LSD into the dolphin and surprizingly enough the dolophins behavior became calm and social(normal by dolphin standards through the duration of the trip and when the dope wore off the animal returned to it's original behavior! nothing to do with the article just thought you all might like this. all of Dr. Lilly's books are quite interesting albeit a little much at times, but if cetations fascinate you, you should read some of his material!

5 / 5 (1) Feb 19, 2010
dear mr lokheed, everything in your discourse suggests a close relationship with the us army. the nick, the poor mastering of language and grammar, the blunt opinions about some animals that are, after all, excellent mine carriers...

and now this marino woman again!

5 / 5 (1) Feb 19, 2010
Seems they're not trying to say they are humans, just that their intellect and self-awareness should bring us to question their internment for our entertainment. Even if they aren't as intelligent as us, if it makes them suffer, it has to stop since it's not necessary.

It is typical human arrogance to think we are superior enough not to have to ponder the way we treat other sentient beings...
1 / 5 (1) Feb 19, 2010
It is not improbable that dolphins are smarter than a lot of, if not most humans. We keep them captive to satisfy our own curiosity of them, and they tolerate this because they are just as curious about us. In many ways we demonstrate a very primitive behaviour, even though we may be using tools to do so. It is wrong to judge a creature's intelligence from within the context of our own being.
5 / 5 (1) Feb 19, 2010
If any extraterrestrials monitor this forum please ignore Lokheed's comments. And bring nice toys if you can...
4 / 5 (2) Feb 19, 2010
We keep them captive to satisfy our own curiosity of them, and they tolerate this because they are just as curious about us.

That's a very Douglas Adams kind of sentiment. Made me smile.

The big grains of cetaceans are employed in echolocation, navigation, and coordination of activities within a "school" of animals. Through sonar, they have high-fidelity volumetric "vision", in addition to their optical vision; this requires a great deal of additional brain matter to process and represent.

Lacking articulated appendages, and consigned to a relatively monotonous environment (compared to land), cetacean cognitive abilities are not so much geared toward tool use or invention, as is the case with the human brain.

So, while they are indeed quite intelligent, and social, the quality of their intellect is rather different and in some ways limited. I wouldn't go so far as to compare them to humans; I'm much more comfortable with an analogy to chimps.
5 / 5 (2) Feb 19, 2010
If we have no compelling need to make them suffer then we shouldn't, if for no other reason than our own intellectual and psychological integrity. It is not a complicated "moral" calculation.
And Lokheed: There's more to life, including a dolphin's life, than being safe and fat.
1 / 5 (2) Feb 20, 2010
I'd prefer that the American soldier in Afghanistan or Iraq, serving there against his own will, should be freed first.

But I do agree that animal suffering should be avoided.

However, dolphins performing at a sea world don't necessarily suffer. If their trainer loves them (instead of being a whip wielding dictator), and if they are given a sense of purpose and joy, the dolphins may well be as happy as those roaming some boring patch of coastal waters.
not rated yet Feb 21, 2010
Dolphins aren't just getting fat in cuddly sea worlds: http://www.4us2be...masacre/
not rated yet Feb 21, 2010
an interesting anecdote: My blood ancestors, the Juaneno of southern cal, regarded dolphins as the "spiritual people" of the sea. They as well as the aborigines of Australia have professed to be able to communicate with them through telepathy. Another strange one for you: I once visited the shedd aquarium in Chicago and saw a beluga there. It picked me out of the crowd as I walked by and followed me, looking directly at me for a few minutes, and as it did so, it let out a series of high pitched shrieks. Ive never had a headache before from any kind of noise, but when that whale opened it's mouth, I suddenly had the strangest tight feeling in my frontal lobes that I could not explain, followed by a lingering headache. Ive since wanted to go back to see if he would do it again. It was definitely an unusual experience, and I was left with the distinct feeling of having formally met this whale, almost like a human acquaintance.

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