Sigh. Certainly the human brain is the most optimized (so far!) for being a human and the elephant's the most optimized for being an elephant. Clearly you need more neurons than a few to get higher functions, but above some (probably tiny) threshold structure dominates. It's like deriving function and performance by counting the number of transistors on a chip.
We see Apple's A9 is currently the peak performer ($/W, $/FLOPS) for a mobile device with a big screen... but is still very very far away from Intel's general purpose chips. Does that mean one is "better"? No, they just picked different optimization points.
Far more interesting is why a chihuahua with a walnut-sized brain is just as smart as an irish wolfhound that has a brain that masses about as much as a whole chihuahua!
I think you need to have a better understanding of how evolution works. It's not the Victorian model where the human is more evolved much less more perfect than any other animal. In fact animals that reproduce faster have more opportunity for evolutionary impact -- the cockroach is far "more evolved" than a human. Consider it a big parallel hill-climbing problem with each animal being a local optimum for its environment.
A human, including its brain, is the best general-purpose device for transmitting genes, but the human brain lacks structures that would be useful to an elephant, and vice versa. Brains are not general-purpose devices.
Consider my dog: the surface area of his nose is probably about the size of a football field and I would bet his olfactory cortex is about the size of his visual cortex (in some breeds, it's probably even larger). Of course our visual system is more dominant than our olfactory system. So that's a simple example...would you really call one of them "inferior" to the other?
[Edit: fixed the amusing typo "hill-sliming" -- we are not snails!]
> It's not the Victorian model where the human is more evolved much less more perfect than any other animal.
In colloquial terms, think we'd find few who'd argue humans flying around in helicopters shooting elephants with high power rifles are not more evolved than said elephants.
> Consider it a big parallel hill-climbing problem with each animal being a local optimum for its environment.
There is rarely "its" environment. Because environment is shared. Especially shared with humans, who have great ability to manipulate said environment (usually for the worse). They will polute it, introduce other species which would end up dominating the food chain, completely change the physical form (built a dam and alter the course of a river), end up enslaving species in order to provide food for themselves. Would you say chickens have evolved and got to an optimal point? Or have they been evolved by humans so they can turn into dinner.
> Consider my dog: ... would you really call one of them "inferior" to the other?
I would call the organism which types on the computer, connected to an artifically created world wide network, and who is able to contemplate the fate of the universe, evolution and other concepts, a bit more evolved ;-)
Domestic animals are more successful right now than the humans breeding them if we count the total mass of organisms sharing similar genes; which IMO simply demonstrates the absurdity of much of our thinking about evolution in terms of winners and losers. (Another example - if you look at "evolutionary success" as the prevalence of patterns in general and not necessarily genes, then simple molecules like H2O are infinitely more successful/prevalent in terms of their total mass than any kind of a living organism, which means that the best way to win the evolution game is not to play. If we think of evolution as a game where winning equals maximizing the number of times a pattern appears in the physical space, then it ought to be one of the stupidest and most pointless games ever.)
> In colloquial terms, think we'd find few who'd argue humans flying around in helicopters shooting elephants with high power rifles are not more evolved than said elephants.
You should try to understand what evolved actually means. What that shows is that we have gained a higher level of tool use than the elephants. Intelligence is not a sign of being more evolved, it is purely a sign of intelligence.
This is like a bird saying that they are more evolved than a human because they can fly without artificial aids.
>...would you really call one of them "inferior" to the other?
I think I would consider the dog brain to be generally inferior, sufficiently so that I would simply label it as inferior. With sufficient general intelligence, you can delegate tasks that your brain is inadequate to accomplish to technology (or possibly other entities, like dogs!), something dogs cannot do and something that makes the human brain clearly superior.
You can argue against human brain superiority without access to technology, but then we're comparing the two in more specific scenarios. Without any particular constraints, the human brain has sufficiently superior general intelligence to make it superior overall.
You have a solipsistic view: you consider the human brain "superior" because it's good at things you want to do. That simply says it's better for humans.
That doesn't mean a dog, whale, elephant or nematode wants to do those things. In fact the "superior" human brain would be useless for a nematode since that brain has support for organs (i.e. peripherals) the nematode doesn't have and requires a lot of energy and other resources the nematode also doesn't have access to. And the mass of nematodes far exceeds the mass of humans on this planet, so who's more successful? Humans are simply more successful at being human and nematodes at being nematoda.
You wouldn't argue that an i7 would be "superior" in a phone (much less an A9 in a laptop!!) so why is the human brain unequivocally better than all others?
I revel in my human brain and would not want to be an animal without opposable manipulators. But hell, seals and narwals have senses I do not and, Asimov aside, I am sorry I'll never know what those feel like.
It's called "anthropocentric" not "solipsistic". Solipsism has nothing to do with it. But except of terminology, I agree with you. I would even go as far as saying, that there's nothing that makes humans objectively "smarter" (not to mention "better") than rocks: it's just that the range of possible actions rocks are to perform is much more narrow than that of humans, and contains just one item — laying around. Which, I might add, rocks are executing much more perfectly than humans are typically performing actions they are to perform.
A lot of animals have brains that are cheaper than human brains, in terms of size and food. But usually when we're talking about what's better, we exclude budget. By those terms, the human brain is vastly superior to almost all others. Just like an i7 crushes every little embedded processor out there.
Being superior and being more optimized for a niche are not the same thing.
While value judgment of any sort requires perspective I don't think it's wrong to prefer our own. Rejecting all value judgements of any sort would simply leave us without anything to converse about.
I think the kind of things people can do have more value than the sort of things a dog can do and further that it's only the dogs limitations that prevent us from appreciating it. Our abilities are nearly a superset of theirs.
Finally survival beyond the scope of your biosphere ultimately requires intelligence of the human sort and that is certainly worth something.
>>While value judgment of any sort requires perspective I don't think it's wrong to prefer our own. Rejecting all value judgements of any sort would simply leave us without anything to converse about.
You have raised a very important point. Sadly I can't upvote it more than once.
Nowadays the political correctness is forcing people to shun from passing on any sort of such judgments. In fact, it has sort of become politically incorrect to call dogs and other animal species to be intellectually inferior to human beings. [1]
Please correct me if I am wrong.
>>Finally survival beyond the scope of your biosphere ultimately requires intelligence of the human sort and that is certainly worth something.
Those neurons not in the pre-frontal cortex are probably helping with things like controlling the complex trunk which contains over 40,000 muscles (compared to the only six hundred and some muscles in the entire human body).
I've read this report before, mainly it was used as a reference doc when debating others about the 10% brain myth. See here, as it directly references the 126 IQ example under "John Lorber and hydrocephalus": http://johnhawks.net/weblog/reviews/brain/development/ten_pe...
It appears the amount of white matter in the brain can vary wildly without having a large effect on cognition (as with the 126 IQ example). Usually it's the cerebral cortex, the outer, wrinkled brain layer that matters most. Humans have more neurons in this region than any other mammal by far.
This squares with the original article, which argues the absolute number of neurons in the cerebral cortex is more accurate for measuring cognition than sheer brain size. So we might derive that brain mass lost due to hydrocephaly is not nearly as important as the cortex neurons retained.
It adds a wrinkle, but appears to be larger due to brain volume rather than density:
However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. .... Our results underscore that correlations between cognitive performance and absolute neocortical neuron numbers across animal orders or classes are of limited value - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4244864/
Which I take to mean we shouldn't rely on one indicator to explain the emergence of consciousness. It used to be thought that brain size dictated intelligence. Corvid tool is one challenge to that assumption. We shouldn't replace brain size with neuron size. It looks like evolution fleshed out multiple paths to achieving certain reasoning behaviors.
>Far more interesting is why a chihuahua with a walnut-sized brain is just as smart as an irish wolfhound that has a brain that masses about as much as a whole chihuahua!
chihuahua has the largest among dogs ratio of brain to the body.
Another thing to note when size of brain is discussed is the Einstein's brain - smaller than average, it had greater ratio of glial/neuron cells and was much more interconnected among other things.
>>Far more interesting is why a chihuahua with a walnut-sized brain is just as smart as an irish wolfhound that has a brain that masses about as much as a whole chihuahua!
This is really interesting claim. If any expert on this matter here on HN provides some more information on whether this claim holds or not, it will be really helpful to this discussion.
For the size comparison I just estimated: a mammal's avg density isn't much more than 1 and the volume of a chihuahua is about the size of my Wolfhound's brain case (I see both kinds of dog daily).
The "intelligence" point is both uncontroversial and well attested: consider, for example, that you can train any dog to an agility course (adapting for size constraints of course) and in dog shows this is very common.
There are certain breeds of dog (or horse) that are considered "more intelligent" than others, but this rarely holds up under scrutiny -- some are more gregarious than others but all are apparently equally trainable to the kinds of tasks humans typically ask. Some are more gregarious than others or have other traits but they are well within the variations humans also exhibit.
The human brain is better than the elephant brain. The fact that the elephant faces extinction at the hands of human brains and is only being saved from extinction by the work of other human brains is evidence at least at some level.
The elephant brain is better than the human brain. The fact that the elephant faces extinction at the hands of human brains and is only being saved from extinction by the work of other human brains is evidence at least at some level.
You could as easily say that snails' brains are better than human brains because some humans try to save snails. It doesn't mean anything about the snails or elephants, it just means the human brains don't all agree on this one topic.
I don't think that's intrinsically a good argument [heuristic]; the Neanderthals were also intelligent and faced extinction at the hands of human brains..
Your first question presupposes that human-like intelligence is the "goal". If it's valuable, some other species could get there; unlikely to be another mammal, but after we kill ourselves off perhaps it will be some dependent of the cockroach or a fish.
Clearly a mutual ancestor of chimps, gorillas and humans did develop human-like intelligence. I'm not sure it's meaningful to ask why, say, chimps didn't develop in that way since they ended up being a subgroup subject to different evolutionary pressure.
Evolution isn't magic, it's just in an inherent process of an adaptive system. Like I wrote above, I think of it as a huge, loosely coupled hill-climbing computation, but the different nodes run at different rates and interact. You could also think of it as a neural net without a directed training system.
I think your second question is very interesting and I have wondered about it too. Ignoring the case of the neanderthalers for a moment, it's likely there were lots of variants who just suffered some environmental issue (e.g. a drought where they lived, or an invasion from some carnivore) that impacted a population too small to survive the threat. (and for purpose of discussion we presume this group were legitimately speciated from us). This happens to animals all the time. So we look back with survivorship bias.
The neanderthalers are more complex since they did survive until very recently and may not have been a completely different species. My guess is the threat they faced was homo sapiens sapiens. Is that an inherent property of humans? Seems like it :-(.
BTW by "human-like intelligence" I assume you mean "able to make complex tools that multiply its own functions in a non-linear fashion, support a complex society, and develop the capability to live apart from the earth". Since a cockroach civilization would have different objectives and metrics from ours their behavior wouldn't look anything like ours either.
It doesn't seem to talk about the plausible explanation that the ratio (of brain mass to body) also matters. So elephants have a bigger one but also loses a lot of its processing power to a greater number of neural signals (which probably increase linearly with weight).
According to this page, humans have the highest ratio except for a few species that have very small brains in absolute size, which probably miss out on benefits to scale.
I would also suggest that they're very disadvantaged in not having developed the tools for more wide scale intergenerstional transmission of cultural knowledge.
Hard to be a philosopher while having to invent philosophy in your head without hearing or speaking with anyone or reading anything. How good of a mathematician can someone become if they have to invent mathematics on a silent island with no books or even their parents teaching them to count? Without language, this is the situation an elephant-philosopher is in...
I heard an interesting argument for what a chance occurrence language is in humans: after all we talk by using the organs we chew with, fashioning our lips and tongues into phonemes.
If the freak "language gene" were given to elephants (spliced into DNA etc) so that they can develop phonemic values over generations using whatever speechlike abilities their mouths do have, it would be interesting to note whether they can develop philosophy then.
But man had modern brain and speech abilities for tens of thousands of years before our cultural situation and heritage became interesting. You likely wouldn't be impressed with the philosophical world view of members of an isolated hunter-gatherer tribe tens of thousands of years ago who had no writing. Interesting, surely, but as an curiosity. Would speaking elephants left to their own devices be the same? Or do humans have higher cognitive processes they cannot match, in addition to lacking our language skills? So that they would not be put at a prototypical human level, but insteqd forever stuck at the elephant level, their new language ability notwithstanding...
Strictly speaking birds don't even have a cerebral cortex. That is, cortex evolved in mammals after the split with the last common ancestor of mammals and birds. So in that sense, birds would be at the very back of the ordering, along with reptiles, fish and the other vertebrates that lack a cortex. That said, birds do have a well developed pallium that seems to play a similar role as cortex does in mammals, even though it is structurally quite different. If you let pallium stand in for cortex, crows would probably do okay.
It seems likely that avian pallium performs similar computations as cortex, despite having a different implementation. The more interesting question, in my opinion, is not who has the most neurons of any particular type, but how those cells enact computations. Does the avian pallium have representations that are similar to mammalian cortex. In other words, does it solve problems in similar ways/using similar algorithms as cortex or did its early divergence allow it to find different solutions?
To me it seems our ability to preserve and share knowledge is far more important for our intellectual pursuits than the individual brain is. E.g. it took hundreds of thousands of years for someone to think up the number 0, and then it spread like wildfire (after the authorities stopped resisting).
What I find curious is that parrots can vocalize at least as well as humans, they show some pretty solid reasoning ability, their tongue is practically an opposable thumb, and yet they don't seem to have developed complex spoken language or technology.
I wonder what's missing from bird brains that would help them with language. Actually, I just had a flash of memory about some part of the brain involved with putting ideas into linear sequences, as we do with words. Maybe that plays a part.
Corvids and cetaceans would be good for future study, but I doubt we're in for much of a surprise.
This is a study in line with interspecies differences. Intraspecies differences still require some teasing out. E.g., how does a Gauss differ from Joe Q. Public?
The elephant has a bigger brain, but it also has a much larger body it has to monitor and control which takes brain power. The sperm whale has an even bigger brain, and an even larger body.
It all comes down to the relative brainsize / bodysize. This wikipedia article describes it: https://en.wikipedia.org/wiki/Encephalization_quotient
And as you can see in that article, our quotient is far the highest of all animals. I find it weird that the authors of the article don't mention these things and do not seem to be aware of this.
Except when it isn't. Dinosaurs had much smaller brains than humans, not just relative to body mass but absolutely. A big body does not necessarily require a proportionally large brain.
They seem to skip the obvious explanation of why we tend to be smarter than Elephants is that our brains have in some ways a better design. It's not all about how many kilos of neurones you have or cows would be discussing metaphysics. Evolution works by random DNA mutations and quite likely we just got lucky in hitting some good ones.
How disappointing. The thing I most wanted out of this article was to learn what was so significant and powerful about the elephant cerebellum. Surely, that means elephants have superior abilities in the aspects relevant to the cerebellum. I want to hear about the amazing things elephants can do that this enables.
Superiority is the wrong word. The author should say human like behavior is correlated with a higher number of neurons in the cerebral cortex.. Additionally, I remember dolphins had more neurons in overall in their cerebral cortex..
We see Apple's A9 is currently the peak performer ($/W, $/FLOPS) for a mobile device with a big screen... but is still very very far away from Intel's general purpose chips. Does that mean one is "better"? No, they just picked different optimization points.
Far more interesting is why a chihuahua with a walnut-sized brain is just as smart as an irish wolfhound that has a brain that masses about as much as a whole chihuahua!