7 ms·

Does not necessarily mean more intelligent.

dredmorbius 5y ago
Good point. It could well be that our brains are more efficient (or more specialised) than earlier human / proto-human brains. Given the prodigious energy expenditure of the human brain, any gain in efficiency or shedding of unnecessary capabilities could well be a net win.
- bpodgursky 5y ago
  I have always found this theory questionable because the shrinkage happened somewhat uniformly across disparate human populations. There's no reason that every significant human subpopulation would suddenly evolve more efficient brains at the same time.
  - klyrs 5y ago
    There's evolutionary pressure to reduce brain size because big heads make childbirth more injurious/lethal to the mom. I find it quite plausible that it would happen everywhere along a similar timeline.
    - BuyMyBitcoins 5y ago
      I see what you’re getting at, but wouldn’t the same pressure to reduce head size also inhibit the heads from getting big in the first place?
      - bpodgursky 5y ago
        Exactly. And clearly there was pressure to downsize heads! But the tradeoff was that we lost brains, and until 40k years ago, that wasn't worth it. But with the advent of proto-civilization, the calculus changed...
      - dredmorbius 5y ago
        The fitness target isn't a stationary one. Larger heads might have been facilitated by a larger pelvic girdle (this seems to be the case in Neadnderthal skeletons AFAIU), which is an adaptation which would enable large (and possibly inefficient) brains, but at a cost for bipedal mobility, speed, and/or efficiency. Supposing a later competitor emerged with 1) smaller and 2) more effcicient brains as well as 3) narrower hips, then the previous advantage would become a (comparative) liability. It's a bit like Clayton Chistensen's Innovator's Dilemma: evolving yourself (or your species) into a corner. Advantageous for a while, but ultimately maladaptive, and hard to back out of. As with my other comments here, all but entirely conjecture.
  - dredmorbius 5y ago
    Disclaimers first: I'm not a geneticist or even remotely close. I'm mostly aware of this dynamic from h. sapies and h. neanderthalensis (or h. sapiens sapiens* and h. sapiens neanderthalensis* comparisons. In a nutshell, Neanderthals were in numerous ways the apparent heavy-duty / high-output model, Sapiens the more efficient / economy model. Neanderthals had larger muscles, shorter limbs (less speed but greater strength, simply on leverage), and larger cranial volumes. All of which would have, everything else being constant, increased overall energy demands. Mind: this is all my own conjecture, though I wouldn't be surprised to find some literature suggesting similar mechanisms. Where Neanderthals were competing against other mammalian species and each other, the differentiation was apparently favourable. Possibly also in an ice-age climage. With Sapiens on the scene ... Neanderthals largely disappeared from the record, though in all likelihood also interbred with Sapiens to some extent. For whatever the reasons, the Neanderthalic adaptations seemed less suitable than the Sapiens ones. The presumption is that this was a fitness selection, though it could well have been other factors (mating preferences, superior numbers for Sapiens, dumb luck and/or chance). But ... in general, while bigger can seem better and more appealing for various reasons, it often is not, and adaptations which require higher energy or have a higher minimum sustaining requirement ... could well prove to be less suitable especially where the environment itself is in transition, or where resources are highly marginal. There is a fair bit of research into the loss of vestigal function, particularly among sequestered cave populations such as blind fish and invertebrates. It turns out that visual processing has high energy demands, and in an environment in which sight conveys no advantage, lack of sight is actually advantageous, as it reduces neurlogical metabolic load (by as much as 1/5 to 1/4 if I'm recalling my sources correctly). In the case of "Dragon Man", we're looking at a new instance and have little data to go on. But other homo variants and general evolutionary trends suggest at the very least possible directions.
vincentpants 5y ago
But it could! I’ve always suspected some form of domestication syndrome affecting our species. https://en.m.wikipedia.org/wiki/Domestication_syndrome https://en.m.wikipedia.org/wiki/Domestication_syndrome
- Nursie 5y ago
  That doesn't suggest a reduction in intelligence .. ?
  - Symmetry 5y ago
    Yes, but being able to work productively in larger groups often means more for sophisticated tool use than an individual's intelligence.
    - astrange 5y ago
      "Intelligence" is a vague complementary attribute like "attractiveness" and it doesn't seem like you can do anything with the concept except make post-hoc fallacies with it. Nothing that "lacks intelligence" (a monkey, a person with dementia, a person who reads slowly) behaves all that similarly or is actually lacking the same single thing that causes them to "not be intelligent".
      - canadianfella 5y ago
        >"Intelligence" is a vague complementary attribute like "attractiveness" and it doesn't seem like you can do anything with the concept except make post-hoc fallacies with it. That’s just something unintelligent people say. It’s very easy to make predictions based on intelligence that are easily testable.
    - namenotrequired 5y ago
      Intelligence of the members is exactly what allows working productively in larger groups. See for instance: dunbar's number and how it was derived
  - 5y ago
astrange 5y ago
Newborn humans have more neurons than adults do, to this day.
- otabdeveloper4 5y ago
  Newborn humans are more intelligent than adults. (If we use the conventional definition of "intelligence" as "capability to learn and acquire new skills".)
  - astrange 5y ago
    Is that the conventional definition? People here seem to be using it as some combination of "sentient" "creative" and "can do math problems in their heads". There's a lot of confusion between future and present capability in its usage.
- nsonha 5y ago
  it could mean more potential for intelligence
- FooBarBizBazz 5y ago
  If I had access to a genetically identical infant, before its aware mind had formed, and I transplanted its brain into my own (suitably expanded) skull, could I grow a larger, coherent, brain? Would the younger neurons give me neuroplasticity? Would this increase my ability to learn? Would people who had undergone this procedure be more prone to schizophrenia -- which I think of as multiple minds trapped together in one brain and body? If cities are more economically productive than separate villages, because they increase communication among people... well, how much higher-capacity a communication channel than brains literally wired together? You can do better than bike lanes, people.
dr_dshiv 5y ago
Especially since human intelligence is distributed — it isn't just in the brain but it is distributed across other people and artifacts. https://en.m.wikipedia.org/wiki/Distributed_cognition https://en.m.wikipedia.org/wiki/Distributed_cognition
idoubtit 5y ago
Among modern humans, brain size is correlated to body size, meaning that, on average, a taller being has a bigger brain, and vice versa. Assuming that brain size is correlated to intelligence implies that, on average, taller people are more intelligent!

Good point. It could well be that our brains are more efficient (or more specialised) than earlier human / proto-human brains. Given the prodigious energy expenditure of the human brain, any gain in efficiency or shedding of unnecessary capabilities could well be a net win.

bpodgursky 5y ago
I have always found this theory questionable because the shrinkage happened somewhat uniformly across disparate human populations. There's no reason that every significant human subpopulation would suddenly evolve more efficient brains at the same time.
- klyrs 5y ago
  There's evolutionary pressure to reduce brain size because big heads make childbirth more injurious/lethal to the mom. I find it quite plausible that it would happen everywhere along a similar timeline.
  - BuyMyBitcoins 5y ago
    I see what you’re getting at, but wouldn’t the same pressure to reduce head size also inhibit the heads from getting big in the first place?
    - bpodgursky 5y ago
      Exactly. And clearly there was pressure to downsize heads! But the tradeoff was that we lost brains, and until 40k years ago, that wasn't worth it. But with the advent of proto-civilization, the calculus changed...
    - dredmorbius 5y ago
      The fitness target isn't a stationary one. Larger heads might have been facilitated by a larger pelvic girdle (this seems to be the case in Neadnderthal skeletons AFAIU), which is an adaptation which would enable large (and possibly inefficient) brains, but at a cost for bipedal mobility, speed, and/or efficiency. Supposing a later competitor emerged with 1) smaller and 2) more effcicient brains as well as 3) narrower hips, then the previous advantage would become a (comparative) liability. It's a bit like Clayton Chistensen's Innovator's Dilemma: evolving yourself (or your species) into a corner. Advantageous for a while, but ultimately maladaptive, and hard to back out of. As with my other comments here, all but entirely conjecture.
- dredmorbius 5y ago
  Disclaimers first: I'm not a geneticist or even remotely close. I'm mostly aware of this dynamic from h. sapies and h. neanderthalensis (or h. sapiens sapiens* and h. sapiens neanderthalensis* comparisons. In a nutshell, Neanderthals were in numerous ways the apparent heavy-duty / high-output model, Sapiens the more efficient / economy model. Neanderthals had larger muscles, shorter limbs (less speed but greater strength, simply on leverage), and larger cranial volumes. All of which would have, everything else being constant, increased overall energy demands. Mind: this is all my own conjecture, though I wouldn't be surprised to find some literature suggesting similar mechanisms. Where Neanderthals were competing against other mammalian species and each other, the differentiation was apparently favourable. Possibly also in an ice-age climage. With Sapiens on the scene ... Neanderthals largely disappeared from the record, though in all likelihood also interbred with Sapiens to some extent. For whatever the reasons, the Neanderthalic adaptations seemed less suitable than the Sapiens ones. The presumption is that this was a fitness selection, though it could well have been other factors (mating preferences, superior numbers for Sapiens, dumb luck and/or chance). But ... in general, while bigger can seem better and more appealing for various reasons, it often is not, and adaptations which require higher energy or have a higher minimum sustaining requirement ... could well prove to be less suitable especially where the environment itself is in transition, or where resources are highly marginal. There is a fair bit of research into the loss of vestigal function, particularly among sequestered cave populations such as blind fish and invertebrates. It turns out that visual processing has high energy demands, and in an environment in which sight conveys no advantage, lack of sight is actually advantageous, as it reduces neurlogical metabolic load (by as much as 1/5 to 1/4 if I'm recalling my sources correctly). In the case of "Dragon Man", we're looking at a new instance and have little data to go on. But other homo variants and general evolutionary trends suggest at the very least possible directions.

vincentpants 5y ago

But it could! I’ve always suspected some form of domestication syndrome affecting our species. https://en.m.wikipedia.org/wiki/Domestication_syndrome https://en.m.wikipedia.org/wiki/Domestication_syndrome

Nursie 5y ago
That doesn't suggest a reduction in intelligence .. ?
- Symmetry 5y ago
  Yes, but being able to work productively in larger groups often means more for sophisticated tool use than an individual's intelligence.
  - astrange 5y ago
    "Intelligence" is a vague complementary attribute like "attractiveness" and it doesn't seem like you can do anything with the concept except make post-hoc fallacies with it. Nothing that "lacks intelligence" (a monkey, a person with dementia, a person who reads slowly) behaves all that similarly or is actually lacking the same single thing that causes them to "not be intelligent".
    - canadianfella 5y ago
      >"Intelligence" is a vague complementary attribute like "attractiveness" and it doesn't seem like you can do anything with the concept except make post-hoc fallacies with it. That’s just something unintelligent people say. It’s very easy to make predictions based on intelligence that are easily testable.
  - namenotrequired 5y ago
    Intelligence of the members is exactly what allows working productively in larger groups. See for instance: dunbar's number and how it was derived
- 5y ago

astrange 5y ago

Newborn humans have more neurons than adults do, to this day.

otabdeveloper4 5y ago
Newborn humans are more intelligent than adults. (If we use the conventional definition of "intelligence" as "capability to learn and acquire new skills".)
- astrange 5y ago
  Is that the conventional definition? People here seem to be using it as some combination of "sentient" "creative" and "can do math problems in their heads". There's a lot of confusion between future and present capability in its usage.
nsonha 5y ago
it could mean more potential for intelligence
FooBarBizBazz 5y ago
If I had access to a genetically identical infant, before its aware mind had formed, and I transplanted its brain into my own (suitably expanded) skull, could I grow a larger, coherent, brain? Would the younger neurons give me neuroplasticity? Would this increase my ability to learn? Would people who had undergone this procedure be more prone to schizophrenia -- which I think of as multiple minds trapped together in one brain and body? If cities are more economically productive than separate villages, because they increase communication among people... well, how much higher-capacity a communication channel than brains literally wired together? You can do better than bike lanes, people.

dr_dshiv 5y ago

Especially since human intelligence is distributed — it isn't just in the brain but it is distributed across other people and artifacts. https://en.m.wikipedia.org/wiki/Distributed_cognition https://en.m.wikipedia.org/wiki/Distributed_cognition

idoubtit 5y ago

Among modern humans, brain size is correlated to body size, meaning that, on average, a taller being has a bigger brain, and vice versa. Assuming that brain size is correlated to intelligence implies that, on average, taller people are more intelligent!