<blockquote>
  <p><em>With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.</em></p>
</blockquote>

<p>Ah, but they also have a complete three dimensions to move in, unlike us humans who only have about 2.5 dimensions to move in.  Also, they have a number of different "limbs": tail, multiple fins, etc.</p>

<blockquote>
  <p><em>Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?</em></p>
</blockquote>

<p>Why not?  How do you accurately measure an intelligence that is structurally different from yours?  You have to know how that intelligence works, and for that to happen you need to overcome the language barrier (which is still an issue with cetaceans, since many people think they're just dumb animals!  Maybe some cetaceans are like primate apes.  Maybe others are like primate humans!).</p>

<hr>

<p><a href="http://www.rickhanson.net/wp-content/files/papers/cetaceans_brains.pdf">Here</a> is a pdf overview of Cetacean brains.
I hope this answers your question:</p>

<p>A few parts pulled from the article:</p>

<p>Cetaceans have very large brains, yes, but humans hold the top of the proportion scale: our brains are larger in comparison to our body size than most other species.</p>

<p>Cetacean brains are, for the most part, like other brains.  That is, they are there for the processing of cognition (among other things).  A large part of this processing power goes to echolocation.  </p>

<p>Regarding similarities between primate and cetacean brains:  </p>

<blockquote>
  <p>the expansion of the insular and cingulate cortices in cetaceans is
  consistent with high-level cognitive functions—such as attention,
  judgment, intuition, and social awareness—known to be associated with
  these regions in primates. </p>
  
  <p>This view is further supported by the
  observation that the anterior insular
  and anterior cingulate cortex in
  cetacean species having the largest
  brains exhibit a large number of large
  layer V spindle neurons, similar to those originally reported
  to be unique to humans and great apes. These particular neurons are
  considered to be responsible for neural networks subserving aspects of social
  cognition.</p>
</blockquote>

<p>Furthermore, though specifically regarding dolphins:</p>

<blockquote>
  <p>Laboratory studies of bottlenose
  dolphins have documented
  various dimensions of their
  intellectual abilities. These include
  an understanding of ... (declarative knowledge); an
  understanding of ... (procedural
  knowledge); an understanding of ... (social knowledge); and
  an understanding of ... (self
  knowledge). All these
  capabilities rest on a strong foundation
  of memory; investigations have
  demonstrated that bottlenose dolphin
  auditory, visual, and spatial memory are
  accurate and robust.</p>
</blockquote>

<p>Lastly: </p>

<blockquote>
  <p>Field studies have documented
  impressive cultural learning of dialects,
  foraging sites, and foraging and
  feeding strategies in cetaceans.</p>
</blockquote>

<p>So, to recap, the cetacean brain lends itself to, among inumerable other things, advanced auditory (sensory), personal (self), and interpersonal processing (social).  Also, dolphins, and maybe other species as well, have advanced memory and language processing capabilities.</p>

CC BY-SA 3.0
2012-02-25T01:29:14.713Z
A good answer, but I am not entirely happy with one detail: `about 2.5 dimensions`. I get what you mean, but I want to point that a fractal dimension is a mathematical concept. And for example it is $d=2.5$ for the [3D quadratic Koch surface (type 2)](http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension) and I guess it its not what you mean. As it _may_ have sense (you can measure fractal dim of mountains or land with trees), I think it is good to reword it in this answer.
Piotr Migdal
CC BY-SA 3.0
2012-02-27T14:34:43.317Z
Aha, not what I meant actually.  :)  I was making a bad joke about humans' limited ability to move in the up/down dimension, as compared to cephalids which have nearly unlimited motion, at least underwater...
BenCole
CC BY-SA 3.0
2012-01-20T15:10:05.710Z
2012-01-20T15:10:05.710Z
BenCole
<p>I think what is happening is a balance of evolutionary cost and resource cost.  </p>

<p>Evolutionary cost is the amount of "effort" that natural selection spends refining a feature.  Effort that could be spent refining other features, such as making it a more efficient swimmer, etc....so it is by no means free.  If you can get the same capabilities with less generations of tweaking, it's all the better.  Evolutionary costs are higher on animals that have longer generations and that there are fewer total animals.</p>

<p>Resource cost is how much energy a feature uses, as well as such costs as the high rate of childbirth deaths caused by big baby skulls squeezing through small pelvises.</p>

<p>Assume that everything else being equal, larger brains produce more cognitive capability.  But on a large animal, there is far less selection pressure to get the maximum "I.Q points per pound of brain," since the relative resource cost of a large brain is much lower on large animals.  So whale brains use largeness, rather than super-sophistication, to get the right level of cognitive capability.</p>

<p>Remember, whales ARE smart, because that intelligence comes cheaply due to the low cost of brain size on a large animal.  They might be the equivalent to, say, an orangutan.  But unlike the orangutan, they don't have the same pressure to keep the brain small, which would have much larger evolutionary costs.</p>

CC BY-SA 3.0
2012-06-17T15:13:43.350Z
I think you need to cite your use of 'evolutionary cost'. I have never come across such a term in evolutionary biology. Evolution does not 'exert effort' to refine features. There is either a selective pressure of a feature or not, and relevant random mutations either happen or don't. In a sexual population many mutations can fixate in a population at the same time and so there is no effort to be divided up. Everything can be 'done' in parallel.
Artem Kaznatcheev
CC BY-SA 3.0
2012-02-24T18:38:50.167Z
2012-02-24T18:38:50.167Z
rob
<p>You commented "Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?".</p>

<p>I would like add a few perspectives.</p>

<p>1)  The notion that intelligence can be measured on a one dimensional scale is not really credible from any scientific perspective.  See <a href="http://en.wikipedia.org/wiki/Theory_of_multiple_intelligences" rel="nofollow">http://en.wikipedia.org/wiki/Theory_of_multiple_intelligences</a>.</p>

<p>2)  It seems human to feel that we are the intelligence ones and those who are most like us are the most intelligent.  We are very casual in the way that we handle this and often don't notice that we are thinking this way.</p>

<p>What I am trying to get at is that we (collectively) are not very good about thinking about intelligence.</p>

<p>But the question you ask translates to me to be "What are Whales and Dolphins doing with their brains?".  That is a huge question and it must surely depend in part on the species you pick.</p>

<p>For the Atlantic Spotted Dolphin species you should check out Denise Herzing who is spending her life trying to answer this question;  See
<a href="https://www.ted.com/talks/denise_herzing_could_we_speak_the_language_of_dolphins?language=en" rel="nofollow">https://www.ted.com/talks/denise_herzing_could_we_speak_the_language_of_dolphins?language=en</a>.</p>

<p>Dolphins, with a brain size similar to ours and Killer Whales with a larger brain seem to spend a lot of their time in tight social groups with a lot of social interaction.  </p>

<p>But overal, it seems we are not yet intelligent enough to figure out what Dolphins are communicating about.</p>

CC BY-SA 3.0
2015-03-23T02:15:13.133Z
2015-03-23T02:55:06.387Z
2015-03-23T02:55:06.387Z
Humphrey Williams
<p>Elephants and whales have brains that are much larger than those of humans. It is presumed that much of their brain is used up for their larger bodies (after all, there is a allometric scaling between brain weight and body weight in mammals).</p>
<ul>
<li>Do elephants and whales really need super-large somatosensory cortices to map to their larger bodies?</li>
<li>Have we mapped out the parts of the brains of a whale or elephant to see which parts of the brain are mapped to which parts of the body?</li>
</ul>
<p>With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.</p>
<p>Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?</p>
<p>I asked the same question <a href="http://sl.reddit.com/r/askscience/comments/ilb2w/what_do_the_superlarge_brains_of_whales_and/" rel="noreferrer">here</a>, though I'm not convinced by any of the answers provided.</p>

<neuroscience><animal-cognition>
What do the super-large brains of whales and elephants map to?
InquilineKea
# What do the super-large brains of whales and elephants map to?

(Asked by: username_0 on 2012-01-19)

Elephants and whales have brains that are much larger than those of humans. It is presumed that much of their brain is used up for their larger bodies (after all, there is a allometric scaling between brain weight and body weight in mammals).

* Do elephants and whales really need super-large somatosensory cortices to map to their larger bodies?
* Have we mapped out the parts of the brains of a whale or elephant to see which parts of the brain are mapped to which parts of the body?

With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.

Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?

I asked the same question [here](http://sl.reddit.com/r/askscience/comments/ilb2w/what_do_the_superlarge_brains_of_whales_and/), though I'm not convinced by any of the answers provided.

**Tags:** neuroscience, animal-cognition


---

## 3 answers

### Answer by username_1 on 2012-01-20. Score: 15

> *With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.*

Ah, but they also have a complete three dimensions to move in, unlike us humans who only have about 2.5 dimensions to move in. Also, they have a number of different "limbs": tail, multiple fins, etc.

> *Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?*

Why not? How do you accurately measure an intelligence that is structurally different from yours? You have to know how that intelligence works, and for that to happen you need to overcome the language barrier (which is still an issue with cetaceans, since many people think they're just dumb animals! Maybe some cetaceans are like primate apes. Maybe others are like primate humans!).

---

[Here](http://www.rickhanson.net/wp-content/files/papers/cetaceans_brains.pdf) is a pdf overview of Cetacean brains.
I hope this answers your question:

A few parts pulled from the article:

Cetaceans have very large brains, yes, but humans hold the top of the proportion scale: our brains are larger in comparison to our body size than most other species.

Cetacean brains are, for the most part, like other brains. That is, they are there for the processing of cognition (among other things). A large part of this processing power goes to echolocation.

Regarding similarities between primate and cetacean brains:

> the expansion of the insular and cingulate cortices in cetaceans is
> consistent with high-level cognitive functions—such as attention,
> judgment, intuition, and social awareness—known to be associated with
> these regions in primates.
>
> This view is further supported by the
> observation that the anterior insular
> and anterior cingulate cortex in
> cetacean species having the largest
> brains exhibit a large number of large
> layer V spindle neurons, similar to those originally reported
> to be unique to humans and great apes. These particular neurons are
> considered to be responsible for neural networks subserving aspects of social
> cognition.

Furthermore, though specifically regarding dolphins:

> Laboratory studies of bottlenose
> dolphins have documented
> various dimensions of their
> intellectual abilities. These include
> an understanding of ... (declarative knowledge); an
> understanding of ... (procedural
> knowledge); an understanding of ... (social knowledge); and
> an understanding of ... (self
> knowledge). All these
> capabilities rest on a strong foundation
> of memory; investigations have
> demonstrated that bottlenose dolphin
> auditory, visual, and spatial memory are
> accurate and username_3ust.

Lastly:

> Field studies have documented
> impressive cultural learning of dialects,
> foraging sites, and foraging and
> feeding strategies in cetaceans.

So, to recap, the cetacean brain lends itself to, among inumerable other things, advanced auditory (sensory), personal (self), and interpersonal processing (social). Also, dolphins, and maybe other species as well, have advanced memory and language processing capabilities.

> **Comments:**
> **username_2**: A good answer, but I am not entirely happy with one detail: `about 2.5 dimensions`. I get what you mean, but I want to point that a fractal dimension is a mathematical concept. And for example it is $d=2.5$ for the [3D quadratic Koch surface (type 2)](http://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension) and I guess it its not what you mean. As it _may_ have sense (you can measure fractal dim of mountains or land with trees), I think it is good to reword it in this answer.  
> **username_1**: Aha, not what I meant actually.  :)  I was making a bad joke about humans' limited ability to move in the up/down dimension, as compared to cephalids which have nearly unlimited motion, at least underwater...  

---

### Answer by username_3 on 2012-02-24. Score: 5

I think what is happening is a balance of evolutionary cost and resource cost.

Evolutionary cost is the amount of "effort" that natural selection spends refining a feature. Effort that could be spent refining other features, such as making it a more efficient swimmer, etc....so it is by no means free. If you can get the same capabilities with less generations of tweaking, it's all the better. Evolutionary costs are higher on animals that have longer generations and that there are fewer total animals.

Resource cost is how much energy a feature uses, as well as such costs as the high rate of childbirth deaths caused by big baby skulls squeezing through small pelvises.

Assume that everything else being equal, larger brains produce more cognitive capability. But on a large animal, there is far less selection pressure to get the maximum "I.Q points per pound of brain," since the relative resource cost of a large brain is much lower on large animals. So whale brains use largeness, rather than super-sophistication, to get the right level of cognitive capability.

Remember, whales ARE smart, because that intelligence comes cheaply due to the low cost of brain size on a large animal. They might be the equivalent to, say, an orangutan. But unlike the orangutan, they don't have the same pressure to keep the brain small, which would have much larger evolutionary costs.

> **Comments:**
> **username_4**: I think you need to cite your use of 'evolutionary cost'. I have never come across such a term in evolutionary biology. Evolution does not 'exert effort' to refine features. There is either a selective pressure of a feature or not, and relevant random mutations either happen or don't. In a sexual population many mutations can fixate in a population at the same time and so there is no effort to be divided up. Everything can be 'done' in parallel.  

---

### Answer by username_5 on 2015-03-23. Score: 1

You commented "Yet, it is apparent (to many people) that whales and elephants don't have drastically higher intelligence than humans. So their extra brain regions have to go somewhere. Where do they go to?".

I would like add a few perspectives.

1) The notion that intelligence can be measured on a one dimensional scale is not really credible from any scientific perspective. See <http://en.wikipedia.org/wiki/Theory_of_multiple_intelligences>.

2) It seems human to feel that we are the intelligence ones and those who are most like us are the most intelligent. We are very casual in the way that we handle this and often don't notice that we are thinking this way.

What I am trying to get at is that we (collectively) are not very good about thinking about intelligence.

But the question you ask translates to me to be "What are Whales and Dolphins doing with their brains?". That is a huge question and it must surely depend in part on the species you pick.

For the Atlantic Spotted Dolphin species you should check out Denise Herzing who is spending her life trying to answer this question; See
<https://www.ted.com/talks/denise_herzing_could_we_speak_the_language_of_dolphins?language=en>.

Dolphins, with a brain size similar to ours and Killer Whales with a larger brain seem to spend a lot of their time in tight social groups with a lot of social interaction.

But overal, it seems we are not yet intelligent enough to figure out what Dolphins are communicating about.


---

