Posted on 08/21/2006 7:26:19 AM PDT by presidio9
Dolphins are dumber than goldfish and don't have the know-how to match a rat, but they're so pumped full of happy chemicals they probably don't care one bit, a new study suggests.
For years, humans have assumed the large brains of dolphins mean the animals are highly intelligent.
But a new study by Paul Manger, a brain-evolution scientist from Johannesburg's University of the Witwatersrand, suggests it wasn't intelligence that spurred the dolphin's big brain -- it was the cold. To survive underwater, warm-blooded marine animals developed brains that have a lot of insulating material, known as glia, but not too many neurons, the grey stuff used for reasoned thinking.
"Goldfish can solve problems that dolphins can't. When a goldfish jumps out of its bowl, it's thinking past its immediate environment. Dolphins don't have the cognitive leap," Dr. Manger said yesterday.
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The same goes for whales because they share the dolphins' brain composition, he said, and could explain why dolphins get caught in tuna nets: They apparently just don't think to jump out.
And while dolphins can be trained to perform sequences of actions, he said, that could be more a sign of good training than intelligence, adding that stimulus-response conditioning is thought to show low intelligence.
Dr. Manger found that whales and dolphins do not have much of a frontal lobe, and that their hippocampus -- the section involved in memory -- is tiny. They instead have a "hyper-abundance" of insulating glia to overcome the thermal challenge, he said.
And while dolphins may not be as smart as people believe, they could be as happy as they seem. Dr. Manger said dolphins have a "huge amount" of serotonin, the brain chemical he describes as "the happy drug."
He drew his conclusions after spending five years reviewing and analyzing previously published data on cetacean brains. His peer-reviewed study appears in the Biological Reviews of the Cambridge Philosophical Society.
But the head of the Vancouver Aquarium's cetacean research program says measuring intelligence by glia and cortex ratios could be as unreliable as the big-brain theory.
Lance Barrett-Lennard said the highly social networks of dolphins indicate they have strong social intelligence, and notes that cetaceans, like humans, rely heavily on vocal communication.
"A dolphin could have a brain the size of a walnut and it wouldn't affect the observations [that] they live very complex and social lives," Dr. Barrett-Lennard said yesterday.
"They keep account of who their friends are, with very complicated hierarchies and allegiances. The other thing is, they have spatial maps. They know exactly where to go when they need to look for certain food."
Dr. Barrett-Lennard theorizes that dolphins developed large brains because their buoyant, aquatic environment never required them to do any differently. In contrast, birds needed very small, efficient brains so they could counter gravity to fly, and humans faced similar needs to walk upright.
He fears that the pro-whaling lobby will pounce on Dr. Manger's conclusions to strengthen its argument that hunting whales is acceptable. "Intelligent or unintelligent -- we often use that as justification for how we treat animals," Dr. Barrett-Lennard said.
Dr. Manger said his research could help humans create a new approach for dealing with whales, dolphins and porpoises, and could change marine-management practices as well.
This story sounds fishy to me.
One has to wonder what the real porpoise of this study was.
Hard-luck Harry finally got a job. Didn’t pay much, but he thought it would be rewarding –- feeding the animals for a traveling circus. After a few days, something went wrong with the refrigeration units, and all the fish for the seals and dolphins spoiled. No suppliers in the area had enough fish to feed all his marine animals, so he called the local veterinarian for some suggestions on alternate foods.
He hadn’t fed the dolphins for nearly 72 hours, so the doc told him to give them anything with a high protein and fat content. The only thing he could find that wasn’t too expensive was a few dozen seagulls the local sheriff had killed to reduce their population. The other animals had already eaten everything else.
When he got back , he discovered that the dolphins had gone crazy, sexually attacking everything in the pens they could get at –- seals, penguins, keepers –- so the owner had quarantined them in a special area between the lions and the elephants. He figured they were just acting out because their feeding routine was interrupted. But the only way to get to their pen was through either the lion cage or the elephant compound.
He’d been having trouble with the elephants lately, so he asked the lion trainer to help him get through to the dolphin tank. The trainer gave him a small clay pot with some mashed stuff that looked like grass, told him to light it and set it upwind from the lions, and wait for 15 minutes. The smoke would affect them like catnip, mellowing them out so they wouldn’t even notice if he stepped on their tails on his way through the cage.
Cautiously, he opened the lion cage and carried a dozen birds through the cage after the big cats all stretched out and yawned themselves to sleep from the effects of the smoke. Harry opened the other door and stepped onto the decking around the tank where he saw the dolphins acting very strangely, rubbing their bodies against each other and indiscriminately trying to mate with both males and females and valves and drains and anything else they could find. He threw each of them two birds, watched them devour the flesh, feathers and all, and went back through the lion cage.
As he snapped the lock on the cage door and stepped down, two US Marshals pinned him against the bars, handcuffed him, and told him he was under arrest.
“Under arrest? What for?” Harry asked, dumbfounded.
“What for? Why, it’s violation of the Mann Act -- ought to be clear to you , you bein’ with a traveling circus and all –- transporting gulls across staid lions for immoral porpoises!”
(don't hit me, Spirit of Allegiance! I don't do this very dolphin.)
Sorry I didn't get back to you sooner. How shellfish of me. I was floundering around when our son called to tell me about his job and his sole employer.
As for this article, I think it was a whale-written report, but Flipper could probably blow-holes in this guy's theory and would more than likely call it a whale of a tail. I don't know if this report will be considered ofishal. What aspout you?
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