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Why are our brains shrinking?

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Re: Why are our brains shrinking?

#151

Post by lambertsimnel »

aceBacker wrote: post #143
owenversteeg wrote: post #74

It seems like the majority of the comments are not taking into account that this trend began approximately 70,000 years ago - slightly before the various things people here are blaming such as TikTok, Google, writing, Javascript and Twitter. Cutting-edge (heh) technology 70,000 years ago was the stone blade as well as the earliest known primitive art. An interesting guide whenever you're trying to put this kind of th…

I think the answer is the same reason the male brain is larger than the female brain on average. The part of the brain that handles fighting. It's a pretty large part of our brains. The reptilian hindbrain that handles violence isn't needed nearly as much now that we have society and civilization. It's shrinking.

In that case, should we expect to find more shrinking among human male brains than among human female brains?

Re: Why are our brains shrinking?

#152

Post by danwills »

matheusmoreira wrote: post #97
vlovich123 wrote: post #76

Earlier quoted context omitted.

You're making a value judgement like "better" and "worse" as if there was a clear global optimum that you can reach. Why do you assume that's the case? Let's assume there even is a global optimum. Why do we think this global optimum would be invariant on environment? We have clear examples of species that fail to adapt to their changing environment quickly enough dying off. If you took the survivors of a change and t…

Surely having sharper and more intelligent humans is an objectively better uncontroversial outcome. If there's even a chance that our environment is somehow downregulating important features such as intelligence, we must find a way to reverse that process.

Is this perhaps too focused on the individual which might not lead to the optimum for the zoomed-out / group (population-level) case?

This reminds me of a meta-system-transition where simplified versions of individual (previously independent) units can lead to a unified cooperative whole that works better at the meta-system level (similar to what led to eukaryotes or to multicellularity). It's like a sacrifice that the individuals make (of things that might have looked like intelligence in the previous context) in order to be able to work together better, and these kinds of transitions have worked out extremely well for life, so far! (I guess I am biased, being alive and everything!?)

Should humans resist the formation of human meta-systems? Human/robot meta-systems? Certainly seems like a good chance that an extremely successful meta-system could be dangerous to the rest of the regular humans!? But if it's actually better, then that's just normal (meta) evolution.

Re: Why are our brains shrinking?

#153

Post by jacquesm »

algebraically wrote: post #72
jacquesm wrote: post #65

Earlier quoted context omitted.

Computers are less than 100 years old, the idea that their existence has lead to brains shrinking is preposterous.

That wasn't the argument. You seem to be saying that the increasing volume of digital information will require new cognitive adaptations and I'm saying that's not the case because I don't need to be as smart to appear smart on a digital medium, I can just rely on external cognitive aids like google.

> You seem to be saying

I'm not.

Re: Why are our brains shrinking?

#155

Post by thro1 »

algebraically wrote: post #5

Because we are being domesticated. Domesticated animals are all dumber than their wild counterparts. Every wild animal that ends up being domesticated ends up with a smaller brain. I should rephrase and maybe say that this doesn't necessarily mean the animals get dumber but they definitely change in the process of domestication and a smaller brain is one of those adaptations. [1] > The reduced amount of white matter…

Is there some study about brain sizes of kindergarten and free-range kids?

Re: Why are our brains shrinking?

#156

Post by pawelmurias »

owenversteeg wrote: post #103
silisili wrote: post #93

Earlier quoted context omitted.

> Cutting-edge (heh) technology 70,000 years ago was the stone blade as well as the earliest known primitive art I think it's important to remember that technology is highly, highly iterative. It's not like if Elon Musk were born 70k years ago we'd have cavemen with electric cars. In fact, if all of us were somehow warped back in time that far, I fear we'd be even worse off. We know how to roll fiber optic networks a…

If an intelligent modern person with some knowledge of history was sent back to 70,000 years ago (70 kya) we'd probably be able to bring significant help to the group - assuming we were accepted into the group and not immediately killed by our ancestors in peak physical condition. Personally, I'd attempt to introduce: - art and culture from the far future (flutes, 42 kya; figurative art, 40 kya) - Simple ovens (29 ky…

> peak physical condition

A lot of our ancestors where not in a particularly good physical condition because of how horrible their nutrition is.

Re: Why are our brains shrinking?

#157

Post by im3w1l »

cogman10 wrote: post #21
algebraically wrote: post #5

Because we are being domesticated. Domesticated animals are all dumber than their wild counterparts. Every wild animal that ends up being domesticated ends up with a smaller brain. I should rephrase and maybe say that this doesn't necessarily mean the animals get dumber but they definitely change in the process of domestication and a smaller brain is one of those adaptations. [1] > The reduced amount of white matter…

I think the only thing I really quibble a bit with is the description of "dumber". Our "domestication" has historically been more that we've gone from a generalist species to a specialist society. With that, things that were previously probably a boon for survival and reproduction become less so (For example, quick reaction times don't matter so much when you have a city wall to keep out predators and a backup huntin…

> Our "domestication" has historically been more that we've gone from a generalist species to a specialist society.

Outsourcing violence to the police is a huge step of domestication.

Re: Why are our brains shrinking?

#158

Post by pawelmurias »

leetcrew wrote: post #115
lostmsu wrote: post #110

Earlier quoted context omitted.

While the first one is probably really wrong, the other two are clearly fine. Imagine a unique cat with an IQ of human. Would you say it is more worth to society, than any other cat? Probably so. Is there a magic IQ threshold that renders other cats not as worthy as humans to not be given the same kind of resources? In a way yes, as you would draw a line. Intelligence is what makes humans humans.

I do love cats, but it's not clear to me what an extremely high IQ cat would be useful for. I suspect it would fall somewhere between lethal and unusually annoying.

A smarter cat plots better ways to murder small animals and calculate more comfortable resting places. Having a smart ones he seemed to be doing all the cat things pretty optimally. For social conflicts him being huge enough that other cats and roaming dogs where scared was a lot more useful. A super high IQ could maybe useful for hunting in dangerous places (it would avoid getting hit by cars and other hazards in cities).

Re: Why are our brains shrinking?

#159

Post by im3w1l »

snek_case wrote: post #98
lumost wrote: post #81

Earlier quoted context omitted.

Alternately, big brains are recessive/selected against in all circumstances except those from 6mya to 70kya. We've generally removed most selective pressure at this point, if having big brains is due to a combination of recessive traits we'd expect brain size to start shrinking.

I was going to say: maybe it's because we're so successful? We dominate our environment so well that we've made the world a much less threatening place, and so it's not as difficult to survive in the world anymore. Less selective pressure means we end up with a less selected population. I don't want to turn this into a political commentary, but the modern age is an extreme example of this. You could be the kind of pe…

Screening and abortion are already used to prevent serious disorders. For instance, a huge fraction of downies are aborted. But subtler things are more challenging.

Re: Why are our brains shrinking?

#160

Post by SideburnsOfDoom »

owenversteeg wrote: post #103
silisili wrote: post #93

Earlier quoted context omitted.

> Cutting-edge (heh) technology 70,000 years ago was the stone blade as well as the earliest known primitive art I think it's important to remember that technology is highly, highly iterative. It's not like if Elon Musk were born 70k years ago we'd have cavemen with electric cars. In fact, if all of us were somehow warped back in time that far, I fear we'd be even worse off. We know how to roll fiber optic networks a…

If an intelligent modern person with some knowledge of history was sent back to 70,000 years ago (70 kya) we'd probably be able to bring significant help to the group - assuming we were accepted into the group and not immediately killed by our ancestors in peak physical condition. Personally, I'd attempt to introduce: - art and culture from the far future (flutes, 42 kya; figurative art, 40 kya) - Simple ovens (29 ky…

> - "Water bottles": animal skins sealed with pitch

Where would you get pitch? Isn't it only found in a very few locations?

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