The Paradox of the Elephant Brain(mitp.nautil.us)
mitp.nautil.us
The Paradox of the Elephant Brain
http://mitp.nautil.us/feature/227/the-paradox-of-the-elephant-brain
10 comments
Going back to the magpie though, they don't have a cerebral cortex at all, yet exhibit remarkably intelligent behavior (tool usage, self-recognition). So, what's up with all the smart corvids?
Non-expert here, but I read some research on this topic. Since avians need to keep their overall weight light, their neurons evolved in such a way as to be smaller and less complex individually than mammals. This allows them to have more neurons in a given area/volume. Also, if I remember correctly, their brains are more decentralized and have fewer specialized structures.
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It's almost as if we don't know everything and the animal brain is actually a bit more complex than a primitive multilayered perceptron neural network!
(Excuse me for the sarcasm.)
(Excuse me for the sarcasm.)
[deleted]
This has been studied a bit. The mammalian strategy of heavily compartmentalizing and duplication, is pretty inefficient.
Is it?
How come that primates like humans, are much smarter than the rest of the world?
How come that primates like humans, are much smarter than the rest of the world?
Because of mass, the number of neurons, how many calories we can toss at them, and how many calories a fetus/newborn can be guaranteed.
Even if you have trainable brain, with neurons that can communicate with more percentage of the brain than a primates. You're still on a diet of hundreds of calories instead of thousands.
Looking at smaller animals cognitive abilities is newish. But does look like it will be going interesting places.
Even if you have trainable brain, with neurons that can communicate with more percentage of the brain than a primates. You're still on a diet of hundreds of calories instead of thousands.
Looking at smaller animals cognitive abilities is newish. But does look like it will be going interesting places.
I'm not an expert here, but I find this interesting enough to have done some recreational reading. What I know is that corvids and parrots have a different brain structure to mammals (they diverged about 300M years ago) but, in an example of convergent evolution, have developed areas that serve the same function as our neocortex. It's called the pallium, and has a very different organisation to our neocortex. Instead of the six layers in our neocortex they have clumps of neurons called nuclei. They also have much higher neuron density than mammals, allowing them to fit more smarts into their tiny heads :-)
A few links:
https://www.sciencedaily.com/releases/2012/10/121001151953.h...
http://www.sciencedirect.com/science/article/pii/S0960982205...
http://www.pnas.org/content/113/26/7255.full
A few links:
https://www.sciencedaily.com/releases/2012/10/121001151953.h...
http://www.sciencedirect.com/science/article/pii/S0960982205...
http://www.pnas.org/content/113/26/7255.full
To follow up on noelwelsh's comment, you might find this review interesting: http://comparative-cognition-and-behavior-reviews.org/2009/v...
It talks about how our understanding of avian brains has changed and why they can be so smart (short answer, we're not sure yet)
The number of neurons is not all there is to it - we know from deep learning that we can retain 95% of the accuracy with just 5% of the weights (synapses). So there could be a 20x variation just from the degree of network optimization. The elephant brain is just 3x the weight of the human brain.
Another aspect - consciousness is not created by the brain - it is a result of the brain being in the world (in other words the "agent" being exposed to experiences). To reduce consciousness to a function of the brain is to overlook a force that is guiding, teaching and limiting the conscious activity. I think consciousness, as a concept, is more related to reinforcement learning than the brain.
Another aspect - consciousness is not created by the brain - it is a result of the brain being in the world (in other words the "agent" being exposed to experiences). To reduce consciousness to a function of the brain is to overlook a force that is guiding, teaching and limiting the conscious activity. I think consciousness, as a concept, is more related to reinforcement learning than the brain.
[deleted]
It's not just weight -- it does seem to actually have more neurons and glia numerically. The rest of your comment stands and is probably the most likely / default hypothesis, but there are others.
What if elephant brains actually do outperform ours but along an axis we're not seeing because... well... it's something we suck so bad at that we can't see it in another being.
A relevant story:
I've seen people with insanely great social abilities. I had a friend once who could walk into a room and tell me the personal situations of everyone and we checked this once by starting a few conversations. She had a near-perfect hit rate at spotting things like people who had recently broken up, people who were unemployed, etc. It was spooky.
I'm nowhere near this good and might be "on the spectrum," though it's also possible that my preference for technical and intellectual stuff from a very early age just wired my brain for them. My brain only has so many neurons so I assume there must be a trade-off in what we dedicate them to. The woman in my story above came from a weird kind of complex abusive family and extended social situation (can't go into it and would be too long), so for her she might have dedicated a ton of mental resources to understanding social environments as a matter of personal safety as a child.
I was much more "spectrum"-y when I was a kid and a teenager. For the first 18 years of my life I was kind of oblivious to deep social cues. My social awareness improved really dramatically in my 18-25 years, and it felt very much like being color blind and then gradually acquiring the ability to see color. I became aware of cognitive abilities and aspects of existence that were all around me for the first 18 years of my life but that did not "exist" for me.
As I acquired these abilities I started to spot them and have respect for them in others. Prior to this I didn't notice any variation in other peoples' social abilities because I couldn't notice variation in an ability I didn't have and couldn't perceive.
Neurons are demanding cells. They eat a lot of glucose and need a lot of fats, oils, and micronutrients for their formation and maintenance. It doesn't make evolutionary sense that elephants would maintain a bunch of neurons that do nothing to boost their fitness. Brains aren't externally visible like antlers, tusks, etc. and so serve no intrinsic display or offense/defense function.
It could be an evolutionary accident of hypertrophy. Evolution is not such a greedy optimizer that this is impossible. But the high cost of brains is certainly suggestive of evolutionary benefit.
Edit: I've brought up these kinds of ideas in other contexts and I've found that they bother some people. People almost get defensive, like it's a personal affront to suggest that there might be alien cognitive abilities. I feel that if we ever do meet actual ET aliens we are going to get some kind of massive reality check. The obligatory XKCD: https://xkcd.com/638/
What if elephant brains actually do outperform ours but along an axis we're not seeing because... well... it's something we suck so bad at that we can't see it in another being.
A relevant story:
I've seen people with insanely great social abilities. I had a friend once who could walk into a room and tell me the personal situations of everyone and we checked this once by starting a few conversations. She had a near-perfect hit rate at spotting things like people who had recently broken up, people who were unemployed, etc. It was spooky.
I'm nowhere near this good and might be "on the spectrum," though it's also possible that my preference for technical and intellectual stuff from a very early age just wired my brain for them. My brain only has so many neurons so I assume there must be a trade-off in what we dedicate them to. The woman in my story above came from a weird kind of complex abusive family and extended social situation (can't go into it and would be too long), so for her she might have dedicated a ton of mental resources to understanding social environments as a matter of personal safety as a child.
I was much more "spectrum"-y when I was a kid and a teenager. For the first 18 years of my life I was kind of oblivious to deep social cues. My social awareness improved really dramatically in my 18-25 years, and it felt very much like being color blind and then gradually acquiring the ability to see color. I became aware of cognitive abilities and aspects of existence that were all around me for the first 18 years of my life but that did not "exist" for me.
As I acquired these abilities I started to spot them and have respect for them in others. Prior to this I didn't notice any variation in other peoples' social abilities because I couldn't notice variation in an ability I didn't have and couldn't perceive.
Neurons are demanding cells. They eat a lot of glucose and need a lot of fats, oils, and micronutrients for their formation and maintenance. It doesn't make evolutionary sense that elephants would maintain a bunch of neurons that do nothing to boost their fitness. Brains aren't externally visible like antlers, tusks, etc. and so serve no intrinsic display or offense/defense function.
It could be an evolutionary accident of hypertrophy. Evolution is not such a greedy optimizer that this is impossible. But the high cost of brains is certainly suggestive of evolutionary benefit.
Edit: I've brought up these kinds of ideas in other contexts and I've found that they bother some people. People almost get defensive, like it's a personal affront to suggest that there might be alien cognitive abilities. I feel that if we ever do meet actual ET aliens we are going to get some kind of massive reality check. The obligatory XKCD: https://xkcd.com/638/
Besides the fact that your story resonates with a few of mine, lets be friends; I think there is a lot of mileage in assessing a few facts: the sheer size of elephants, their defenseless young, the complexity of their social relationships, and their general relationship with would-be predators.
I'd suggest that piloting these factors (reducing risk, advancing social relationships, developing the behaviour of their young) requires a wide variety of exacting performance in a complex environment.
I'd suggest that piloting these factors (reducing risk, advancing social relationships, developing the behaviour of their young) requires a wide variety of exacting performance in a complex environment.
Although I don't disagree with your perspective that there could be additional senses invisible to us, I think the explanation for the size of the elephant brain is ultra-simple:
"The cerebellum receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity."
Huge body = huge cerebellum
"The cerebellum receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity."
Huge body = huge cerebellum
I'm sure the trunk alone requires lots of neurons to manipulate.
"The superior cognitive capabilities of the human brain over the elephant brain ..."
Are we sure our cognitive capabilities are superior? How do we know we've been doing meaningful experiments?
Are we sure our cognitive capabilities are superior? How do we know we've been doing meaningful experiments?
Coz there are no elephants posting on HN?
True, though I feel compelled to post the standard rebuttal:
> "On the planet Earth, 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 - whilst 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 reasons."
> "On the planet Earth, 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 - whilst 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 reasons."
That could have more to do with our versatile anatomy than a difference in cognitive capabilities.
But that is exactly the point: the brain draws its cognitive power from the number of inputs and not from mass.
Just think of the human hand or the mimicry we can express and how many muscles and associated sensoric feeds our brain continuously. Mass is relevant, but up to a certain degree.
Just think of the human hand or the mimicry we can express and how many muscles and associated sensoric feeds our brain continuously. Mass is relevant, but up to a certain degree.
Aren't these interchangeable?
I mean, yes you got hands and fingers, but they work because they have nerves in them and those are basically extensions of the brain.
I mean, yes you got hands and fingers, but they work because they have nerves in them and those are basically extensions of the brain.
[deleted]
"On the internet, nobody knows you're a dog."
;)
;)
Cognitive ability also has implications for adaptability. Elephants don't seem to be able to adapt to deal with human poachers very well, and as a result are in danger of extinction.
The encephalization quotient seems to suggest that a certain amount of brain-power is required to process nerve signals subconsciously (pain/touch/etc.). Larger animals have more nerves, and therefore need larger brains to perform the same abstract thinking activies, i.e. IQ. We can further combine this with the diminishing return of further reducing the brain size for an animal that is already large/ consuming large amounts of resources.
a great read -- almost as good as Franz de Waal's "Are We Smart Enough to Know How Smart Animals Are?" (where this study and others are cited) https://www.amazon.com/Are-Smart-Enough-Know-Animals/dp/1783... .
I think the article could be significantly shorter. It says the same thing about six times.
It bugs me when a complicated neural phenomenon reduces to "size matters".
I don't get the reference to cooking our food. Why does cooking our food enable us to have a bigger cortex?
Cooking food breaks down the cell walls and so makes it much easier to digest. So you can get more of the calories out of the food you consume. You spend less time gathering and eating and free up time for thinking.
> You spend less time gathering and eating and free up time for thinking.
I think it's the other way around. We got bigger brains in the first place because our ancestors discovered fire and were able to eat cook foods that provide more calories. Therefore they progressively were able to sustain larger and larger brains. A gorilla for example has one of the largest brains for primate and they need to spend most of their days foraging in order to function. A human brain would be impossible to sustain without cooked foods.
I think it's the other way around. We got bigger brains in the first place because our ancestors discovered fire and were able to eat cook foods that provide more calories. Therefore they progressively were able to sustain larger and larger brains. A gorilla for example has one of the largest brains for primate and they need to spend most of their days foraging in order to function. A human brain would be impossible to sustain without cooked foods.
> A human brain would be impossible to sustain without cooked foods.
How do we explain the survival of people that eat only raw foods even today? Wouldn't that argue against your theory?
I suppose we're speaking about a population and that there will be individual exceptions. But even in a population, shouldn't raw food eaters die sooner or be worse off than cooked food eaters on average?
How do we explain the survival of people that eat only raw foods even today? Wouldn't that argue against your theory?
I suppose we're speaking about a population and that there will be individual exceptions. But even in a population, shouldn't raw food eaters die sooner or be worse off than cooked food eaters on average?
I guess it could be argued that raw food dieters now have access to rich foods like oils, avocados, sprouted legumes and grains, nuts and seeds, etc. That makes the diet far easier than it would have been even 100 years ago, I think.
I'm not in favor or opposed to the person you're responding to. Just thinking about how humans eating a raw diet are different from other animals doing so.
I'm not in favor or opposed to the person you're responding to. Just thinking about how humans eating a raw diet are different from other animals doing so.
Right, humans have a massive global supply chain available to them. The variety of foods available to a raw food dieter probably come from multiple continents and travel hundreds or thousands of miles to get to them. Obviously the energy expenditure required makes this sort of diet (and really any modern diet) unsustainable on just the calories consumed by eating.
One problem with that is the fact that people (at least in the west) who choose to eat raw food are usually health conscious and comparably affluent. This biases the sample. Furthermore, the issue is complicated by the effects on adults vs children.
People don't tend to survive on a raw diet, in the evolutionary sense. I don't see anything scientific at the moment (because studying diet is hard + pre-coffee apathy), but an internet search for "raw food menstruation" indicates that the most common next word is "stops".
"Survival," in the evolutionary sense, doesn't just mean "living into old age" but "reproducing successfully", which paused menses preclude.
"Survival," in the evolutionary sense, doesn't just mean "living into old age" but "reproducing successfully", which paused menses preclude.
The "even today" part destroys the entire question. Obviously, you would not survive on uncooked food 400 years ago as there were no refrigerators (unless you were a king or something, and even then).
Indeed, the brain consumes about 20-25% of the energy and dissipates around 40% of the body heat.
( I swear I need of of those [0], my head - short hair nonetheless - is sweating like hell in the night )
[0] https://www.amazon.com/Mediflow-1006-06-Original-Waterbase-P...
( I swear I need of of those [0], my head - short hair nonetheless - is sweating like hell in the night )
[0] https://www.amazon.com/Mediflow-1006-06-Original-Waterbase-P...
> Therefore they progressively were able to sustain larger and larger brains.
As far as I know, that's not how evolution works. You don't get a feature just because you can sustain it. There's a random mutation and everybody who doesn't get it dies or fails to have offspring.
So in your theory, what was the mutation (or phenotype) and what was the environmental pressure that killed off the non-mutants? And how does it relate to using fire?
As far as I know, that's not how evolution works. You don't get a feature just because you can sustain it. There's a random mutation and everybody who doesn't get it dies or fails to have offspring.
So in your theory, what was the mutation (or phenotype) and what was the environmental pressure that killed off the non-mutants? And how does it relate to using fire?
Pet theory time: There's a lot of speculation about why human females have greatly enlarged breasts compared with other primates. These theories usually revolve around some alleged similarity between boobs and bums, which let's face it, is quite a stretch, especially when you consider other primates. A female chimpanzee's chest looks absolutely nothing like its butt.
However, humans do have much larger brains than other primates, and those brains grow very fast immediately after birth. My theory is that after the advent of cooking, human brains were able to increase in size thanks to the increased dietary energy density of our new diet. Human breasts then had to increase in size in proportion with the nutritional requirements of those infant brains, which had to grow faster than previously.
However, humans do have much larger brains than other primates, and those brains grow very fast immediately after birth. My theory is that after the advent of cooking, human brains were able to increase in size thanks to the increased dietary energy density of our new diet. Human breasts then had to increase in size in proportion with the nutritional requirements of those infant brains, which had to grow faster than previously.
> There's a lot of speculation about why human females have greatly enlarged breasts compared with other primates. These theories usually revolve around some alleged similarity between boobs and bums,
That's the distorted popular version. The more common scientific version, AFAICT, is that they evolved in certain other upright primates to resemble swellings in the genital/buttock region of non-upright forbears and provide similar sexual signalling.
> Human breasts then had to increase in size in proportion with the nutritional requirements of those infant brains, which had to grow faster than previously.
This speculation would make sense if there was a relation between the quantity of fatty tissue which determines breast size and milk production. But, there isn't, so...
That's the distorted popular version. The more common scientific version, AFAICT, is that they evolved in certain other upright primates to resemble swellings in the genital/buttock region of non-upright forbears and provide similar sexual signalling.
> Human breasts then had to increase in size in proportion with the nutritional requirements of those infant brains, which had to grow faster than previously.
This speculation would make sense if there was a relation between the quantity of fatty tissue which determines breast size and milk production. But, there isn't, so...
It still works if initially milk-gland size was selected for, followed by runaway sexual selection. :)
Would be a great pet theory if there were a positive correlation between breast size and milk supply. There isn't. In fact, there's some research to suggest a negative correlation between BMI and breastfeeding quality and duration. [0]
[0] https://www.ncbi.nlm.nih.gov/pubmed/22481622
[0] https://www.ncbi.nlm.nih.gov/pubmed/22481622
You seem to be conflating BMI with breast size? While that's true to some extent, you'd have to control for obesity. Breasts are made up of milk glands surrounded by fat, and the varying ratio of milk gland to fat is why overall breast size doesn't correlate well with milk production.
My theory still works if initially, female pre-humans with larger milk glands were able to better feed their young and so had higher survival rates, while male pre-humans evolved to prefer larger milk glands. After a point, runaway sexual selection caused breast size to increase independently from the pressure on milk production.
My theory still works if initially, female pre-humans with larger milk glands were able to better feed their young and so had higher survival rates, while male pre-humans evolved to prefer larger milk glands. After a point, runaway sexual selection caused breast size to increase independently from the pressure on milk production.
IIRC humans are the only (or one of very few?) mammals to have permanent breasts. In most mammals, breasts are a turn-off for the male because they signify inability to give birth right now. In humans, breasts are a turn-on for the male, for unknown reasons.
I would guess that the reason they're large and the reason they're permanent are related. One causal chain might be (permanent breasts -> males like breasts -> breasts grow), but others are possible. I suppose it might be that non-permanent breasts wouldn't be able to grow to the size they need to be, for whatever reason they need to be that size?
(In case it wasn't clear, I have no expertise in this area, and you shouldn't listen to what I have to say.)
I would guess that the reason they're large and the reason they're permanent are related. One causal chain might be (permanent breasts -> males like breasts -> breasts grow), but others are possible. I suppose it might be that non-permanent breasts wouldn't be able to grow to the size they need to be, for whatever reason they need to be that size?
(In case it wasn't clear, I have no expertise in this area, and you shouldn't listen to what I have to say.)
My pet theory is that large breasts are correlated with some other trait that confers reproductive success, so attraction to large breasted women has been weakly selected for.
One interesting possibility is that breast tissue influences maternal drive. A combination of neural activity and hormone secretion is possible and would do the trick nicely.
One interesting possibility is that breast tissue influences maternal drive. A combination of neural activity and hormone secretion is possible and would do the trick nicely.
OK, that makes sense. Thanks :)
Interesting that intelligence bootstraps like this. Get smart enough to use fire and that allows you to grow more neurons and get smart enough to make... wheels? Computers? What's the next leap after fire?
Interesting that intelligence bootstraps like this. Get smart enough to use fire and that allows you to grow more neurons and get smart enough to make... wheels? Computers? What's the next leap after fire?
Cooking also eliminates a large number of diseases which increases lifespan and health.
Next, you'd want cutting tools to separate your food into clothes parts and eating parts. Use bladders for storing water, which (along with clothes) allows for safer travel and bigger hunting/gathering ranges. Cutting tools also help make good weapons.
With a larger range and easier hunting, you won't have to be as nomadic to find food, so you can start permanent settlements. Find somewhere where plants will grow with regular flooding. Learn to make clay brick and pots in your fire, and you can now store food, seeds, and water. More time now to figure out how to control the flooding process so you lose less crops and can grow on drier land.
Next, you'd want cutting tools to separate your food into clothes parts and eating parts. Use bladders for storing water, which (along with clothes) allows for safer travel and bigger hunting/gathering ranges. Cutting tools also help make good weapons.
With a larger range and easier hunting, you won't have to be as nomadic to find food, so you can start permanent settlements. Find somewhere where plants will grow with regular flooding. Learn to make clay brick and pots in your fire, and you can now store food, seeds, and water. More time now to figure out how to control the flooding process so you lose less crops and can grow on drier land.
I was more interested in the physiological changes than the social ones. If fire allows a brain to grow more neurons because cooking, does farming allow yet more neurons? Or animal domestication?
Maybe language? That surely changes our brain structure? Did that come before fire? We know that other animals have rudimentary language, so is language a precursor to fire? Is it a prerequisite for fire?
Maybe language? That surely changes our brain structure? Did that come before fire? We know that other animals have rudimentary language, so is language a precursor to fire? Is it a prerequisite for fire?
This is a field of active research -- the increase in hominin / human cognitive capabilities, particularly as reflected in the anthropological record.
Sander van der Leeuw, of the University of Arizona / Santa Fe Institute, is among the researchers looking at this. Part of the process is tracked through the complexity of stone tools, which (he argues) is related to short-term working memory and the number of items that can be maintained there.
As to causality:
* Fire, cooking, and food preparation: increase food availability, decrease the uncertainty and energy required for food gathering.
* Tools, language, and simple structures: cooperative and complex arrangements. Possibly not so much the cause of mental development as a selection filter: those with better brains can work together in more complex societies.
* Agriculture, writing, cities: This pretty much sparked like a fire and took off immediately, throughout the Asian-African-European supercontinent, and, somewhat less spectacularly, in parts of the Americas.
* More recent developments may not have occurred over a sufficient period of time as to be profoundly evolutionary, though I wouldn't dismiss the thought. Still, the process is clearly cumulative.
You might also like to poke around at the History of Information website:
http://www.historyofinformation.com/
Also David Christian's "Big History" concept:
https://en.m.wikipedia.org/wiki/Big_History
Sander van der Leeuw, of the University of Arizona / Santa Fe Institute, is among the researchers looking at this. Part of the process is tracked through the complexity of stone tools, which (he argues) is related to short-term working memory and the number of items that can be maintained there.
As to causality:
* Fire, cooking, and food preparation: increase food availability, decrease the uncertainty and energy required for food gathering.
* Tools, language, and simple structures: cooperative and complex arrangements. Possibly not so much the cause of mental development as a selection filter: those with better brains can work together in more complex societies.
* Agriculture, writing, cities: This pretty much sparked like a fire and took off immediately, throughout the Asian-African-European supercontinent, and, somewhat less spectacularly, in parts of the Americas.
* More recent developments may not have occurred over a sufficient period of time as to be profoundly evolutionary, though I wouldn't dismiss the thought. Still, the process is clearly cumulative.
You might also like to poke around at the History of Information website:
http://www.historyofinformation.com/
Also David Christian's "Big History" concept:
https://en.m.wikipedia.org/wiki/Big_History
fascinating, thanks :)
Widespread caesarean section? It would allow brains to grow bigger eliminating the main bottleneck - birth canal. But that's ahead of us.
Fire led to agriculture and metal working, which in turn led to society and war. The rest snowballs from there.
Chimpanzees have war, none of the other stuff is required for that.
Ants have war too.
Animals don't have the A bomb.
Neither did humans, for the first 99.856% of their existence.
There is no indication that society did not exist before Fire. A lot of apes are social animals and they don't have any fire at all.
maybe domesticating other animals such as horses, pigs, and cows?
By following this logic, would Dogs evolve to be more and more intelligent, given that we feed them nothing but a high-calorie diet with zero need for any survival skills? I suspect that high intelligence does not give them any evolutionary advantage and therefore wouldn't become dominant, but then humans do like "smart" dogs and could selectively breed them for intelligence. No?
this seems like something we could test... selective breeding for smarter dogs. Mind you, we'd have to establish a metric for smarter first.
Sheepdogs and their ability to control a mob of sheep always seemed to me to be pretty damned smart...
Sheepdogs and their ability to control a mob of sheep always seemed to me to be pretty damned smart...
[deleted]
One of the things it does is free up our skull to have more realtive space for the brain. Chewing uncooked food requires very robust teeth, jaws, and musculature to power the jaws. By cooking food, it is easier to chew so instead of having massive jaws and teeth, we can have much smaller jaws and teeth and more room for brain.
tldr; The article states:
"The superior cognitive capabilities of the human brain over the elephant brain can simply—and only—be attributed to the remarkably large number of neurons in its cerebral cortex."
which simply does not follow. Well, that and we cook!
"The superior cognitive capabilities of the human brain over the elephant brain can simply—and only—be attributed to the remarkably large number of neurons in its cerebral cortex."
which simply does not follow. Well, that and we cook!
No, sorry, it's completely wrong "tldr".
Instead, the author presents the first ever counting of the cells in the different parts of the elephant brain using a new method, different from the previous attempts, which results in the different numbers for the different sections of the brain. The new result shows that the elephant brain has indeed more cells than the human one, but that the distribution is different.
To those who don't know: cerebellum is the part of the brain at the back of the skull in vertebrates, in humans it's in the lower area of the brain.
http://brainmadesimple.com/cerebellum.html
Look at the brains compared:
http://natureinstitute.org/pub/ic/ic5/Images/IC5_page13.gif
The Cerebral Cortex of the elephant looks bigger, but, according to the author, has 5.6 billion neurons, compared to the 16 billion neurons in human's:
http://brainmadesimple.com/cortex-and-lobes-of-the-brain.htm...
This is new, as the estimates of the count of the cells of in the different parts of the brain of elephant varied before.
See nickledave's post for the link to the scientific work about the the method.
Instead, the author presents the first ever counting of the cells in the different parts of the elephant brain using a new method, different from the previous attempts, which results in the different numbers for the different sections of the brain. The new result shows that the elephant brain has indeed more cells than the human one, but that the distribution is different.
To those who don't know: cerebellum is the part of the brain at the back of the skull in vertebrates, in humans it's in the lower area of the brain.
http://brainmadesimple.com/cerebellum.html
Look at the brains compared:
http://natureinstitute.org/pub/ic/ic5/Images/IC5_page13.gif
The Cerebral Cortex of the elephant looks bigger, but, according to the author, has 5.6 billion neurons, compared to the 16 billion neurons in human's:
http://brainmadesimple.com/cortex-and-lobes-of-the-brain.htm...
This is new, as the estimates of the count of the cells of in the different parts of the brain of elephant varied before.
See nickledave's post for the link to the scientific work about the the method.
Furthermore the Long-finned pilot whale has been shown to have more neurons in the Cerebral cortex than humans. Given the lack of large-scale research in this area, it is not unreasonable to think that several other dolphin species could also beat this count.
https://en.wikipedia.org/wiki/List_of_animals_by_number_of_n...
https://en.wikipedia.org/wiki/List_of_animals_by_number_of_n...
The author of the article argues that stereology is less suited for making the whole brain cell counts, and it can be that her method gives different results, just like it gave for elephants:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4380666/
"Subsequent work using computer simulations, however, revealed that a considerably larger number of cells should be counted (e.g. 700–1,000, Schmitz and Hof, 2000). It is possible that too small of a sample size may explain some of the discrepant results seen in stereology studies."
Of course there's chance that her approach will confirm the current estimates for dolphins, and then the simple count of the neurons in the neocortex will be too simple explanation to be valid.
In computer terms, it's easy to show: the transistor count of the CPU is not the only count that can predict the suitability of CPU for some specific tasks. Her research showed that the brains of elephants do have bigger total count of the neurons, compared to the total count of the neurons of human brains.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4380666/
"Subsequent work using computer simulations, however, revealed that a considerably larger number of cells should be counted (e.g. 700–1,000, Schmitz and Hof, 2000). It is possible that too small of a sample size may explain some of the discrepant results seen in stereology studies."
Of course there's chance that her approach will confirm the current estimates for dolphins, and then the simple count of the neurons in the neocortex will be too simple explanation to be valid.
In computer terms, it's easy to show: the transistor count of the CPU is not the only count that can predict the suitability of CPU for some specific tasks. Her research showed that the brains of elephants do have bigger total count of the neurons, compared to the total count of the neurons of human brains.
"No, the human brain does not have more neurons than the much larger elephant brain—but the human cerebral cortex has nearly three times as many neurons as the over twice as large cerebral cortex of the elephant."
Does the mass of neurons in the cerebellum give the ele' any greater capability? Longer memory for revenge, perhaps?
Does the mass of neurons in the cerebellum give the ele' any greater capability? Longer memory for revenge, perhaps?
Probably has to do with control of the trunk and "infrasonic vocalizations" http://www.karger.com/Article/PDF/345565
if you believe the cerebellum mainly contributes to movement. Some argue that it also contributes to "cognition", as Herculano-Houzel points out. Interesting that her group previously reported that, across evolution, brains maintain a linear relationship between number of neurons in neocortex and number of neurons in the cerebellum:
https://www.ncbi.nlm.nih.gov/pubmed/20300467/.
The finding that 97.5% of neurons in the elephant brain are in the cerebellum would seem to contradict the idea that brains maintain a constant neocortical/cerebellar neuron ratio. The elephant paper attributes the huge number of cerebellar neurons to sensorimotor input, i.e., probably trunk stuff: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4053853/
Herculano-Houzel has published a number of surprising findings using the novel technique she invented for counting cells in the brain. In case you're interested: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4380666/