Dolphins are dumb?
For years, humans have assumed the large brains of dolphins meant the mammals were highly intelligent.
Paul Manger from Johannesburg’s University of the Witwatersrand, however, says it is not intelligence that created the dolphin super-brain — it’s the cold.
To survive underwater, these warm-blooded animals developed brains that have a lot of insulating material — called glia — but not too many neurons, the gray stuff that counts for reasoned thinking.
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Yet while dolphins aren’t as smart as people tend to think, they are as happy as they seem. Manger said dolphins have a ”huge amount” of serotonin in their brains, which is what he described as ”the happy drug.”
While the scientific aspect of these claims is beyond the scope of Haibane.info, let us remember what the Guide had to say:
Man had always assumed that he was more intelligent than dolphins because he had achieved so much – the wheel, New York, wars and so on – while all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man-for precisely the same reason.
Discuss.
The article is a hefty 46 pages, so I won’t read it before posting a response. Based on my skimming, his hypothesis is that water temperature can explain the size of a dolphin’s brain, but in my experience, trying to attribute any evolutionary outcome to a single selective pressure is a risky proposition. Of course, I’m not certain that the large brain equals intelligence is on sound footing either.
Has anybody visting this site worked with dolphins? Having been raised in a culture that believes they are intelligent, that’s where my bias is and I have no actual experience to dispute it.
I actually saw some interesting volumetric studies on pubmed with dolphin brains and MRI. ex-vivo of course. I’ve been saying for years that we need to do in vivo MRI of dolphins, but of course the main problem is that you’d need to either keep the dolphin suitably wet while in the scanner (which given that its not a naturally tenable position for a dolphin, might skew the results of fMRI at the very least), or figure out a way to do MRI underwater (talk about your coil loading problems!)
and of course, we’d probably needto use the body coil just for neuro 🙂 Actually, maybe just go with surface coils for that matter. Hmm. Does Invivo Corp make transmit/receive surface coils?
I promise I am re-launching the MR blog soon so we can discuss this stuff in more technical detail 🙂
BTW Kevin if you’ve got a link to the 40-page article, do share. I didn’t see that…
I don’t know if a link will work since it’s probably subscription based, but I’ll email it to you.
MRI of dolphins would be cool. I’ve read some work on lobsters(?) that was done in water. The loading would be a problem, but so would keeping the dolphin still. How would you protect its hearing during the scans? The seem to be more sensitive to sound than humans. I think it would be a lot of fun to try though, of course I’m also somebody who thinks MRI of insects is a good idea. 😀
But in the end, the only way to test for function is to…well, test for function, which MRI would allow.