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Why are our brains shrinking?

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Re: Why are our brains shrinking?

#191

Post by kazinator »

Brain size is a bit of a red herring. Elephants have 3X the brain mass compared to humans. Though no dummies, but still.

When we think of brain and size, we naturally think of the connection to the intellect. But intellectual activities require patient and slow application of the brain, using external tools like making notes, drawing diagrams and checking one's work for mistakes.

Intellectual pursuits are not actually what the brain is good at. If we make an analogy to computing, it's almost like the intellect is a software layer that is bootstrapped on top of the brain in spite of its shortcomings, using some slow, inefficient scripting language. It's not native to the brain.

An example of what the brain is natively good at is real-time visual processing and control, like navigating in a complex environment full of obstacles and dangers. You don't have to concentrate your intellect for minutes at a time to tell apart a shape from the background; you just point your eyes at it and it pops out at you instantly and effortlessly, thanks to a power in the brain that you can't even control consciously. (Try as you might, you can't not see the shape.)

This is probably why domestication shrinks brains. Perhaps you don't need that much real-time processing in the relatively stable, calm, boring domestic environment.

Re: Why are our brains shrinking?

#192

Post by scoofy »

hchasestevens wrote: post #172
scoofy wrote: post #39

Earlier quoted context omitted.

Whoa... whoa... let's unpack all the intense presuppositions you're packing in here: "Domestication" is just a word for a natural evolutionary processes in a symbiotic system. The concept that "domestication" is like, actually a thing apart from evolution is a vastly more difficult idea to parse than it appears on it's face. >Domesticated animals are all dumber than their wild counterparts. I mean... again... there a…

> "Domestication" is just a word for a natural evolutionary processes in a symbiotic system. The concept that "domestication" is like, actually a thing apart from evolution is a vastly more difficult idea to parse than it appears on it's face. In mammals, there is a well-established "domestication syndrome" with a specific proposed underlying mechanism and associated symptoms, including many observed in humans in com…

The concept that some animals are able to be domesticated, generally, while other's are not, lends itself to the idea that drift toward docile qualities is probably working in the domesticator's favor, and is not an inherent quality of domestication as a concept.

The idea that we have an idea of a thing we can readily point at, does not mean that thing is the driving force behind it. It's just a post hoc argument. We can't domesticate zebras, we can domesticate horses. The idea that 'domestication' is a force, rather than a result of evolutionary pressure of a symbiotic relationship shows that the domestication can't be the driving force. It's just evolution.

I'm not arguing the concept that domestication syndrome doesn't exist. I obviously defer to these experts, I'm just arguing that the concept that free, independent humans 'domesticate themselves' is effectively nonsensical on it's face, as domestication, as such, requires symbiosis and controlled breeding, and is simply not possible for many species.

Re: Why are our brains shrinking?

#193

Post by vlovich123 »

matheusmoreira wrote: post #165
danwills wrote: post #152

Earlier quoted context omitted.

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 t…

> Should humans resist the formation of human meta-systems? Human/robot meta-systems? No. I'm saying humans should not lose abilities or features because of it. We should be able to live comfortable lives and still maintain peak physical and mental performance. Any changes in our nature should not go against that.

We specialize though. Some people might be able to maintain peak mental performance. Others peak physical. Some might be better at social things to make sure we have a cohesive well-functioning society. There's probably thousands of character traits and some are going to invariably be tradeoffs in our genome/social conditioning. There's a reason there aren't Einstein-level intelligences running around every day doing body building, modelling, race car driving all at once. You have to choose what you spend your time on and most people choose to intersect that with natural abilities and interests.

Also, assuming the conclusions of the article in any way prove a shift in intelligence (it doesn't), you'd still be looking at averages which tells you nothing about the effect it has on total number at population. Maybe there's an upper bound of "smart" people or "strong" people modern society demands. Certainly as a skill becomes more commoditized it becomes less valuable economically. Maybe we've got too many smart people now because a lot of people saw the explosion in value of such careers?

Re: Why are our brains shrinking?

#194

Post by drran »

arp242 wrote: post #183
owenversteeg wrote: post #103

Earlier quoted context omitted.

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…

I've sometimes wondered about this as well. We can all understand how saws work; but can you actually make one from scratch? How about a rope? Do you know where to find the right kind of fibre, how to correctly process it, and then make it in to a functional rope? Do you have the know-how to functionally domesticate wild animals and cultivate crops? I'd consider myself a pretty handy guy, but if I were whisked away t…

Primitive saw is just a rope + sand + water.

The problem was not to make things, ancients were able to produce few very advanced tools, mechanisms, and technologies, but to save them and pass knowledge of making them to future generations.

To make a dent, you will need a tool for mass spreading of knowledge en masse: a church, a library, a copier, or a book making machine.

Re: Why are our brains shrinking?

#195

Post by snek_case »

SamoyedFurFluff wrote: post #123
snek_case wrote: post #98

Earlier quoted context omitted.

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…

Wouldn’t being able to retain maximal genetic diversity actually be a good thing species wide though? Because it also means we have ever bigger achievers in ever more niche but valuable roles.

We can probably keep 99% of the diversity and just filter out diseases that significantly decrease quality of life.

Re: Why are our brains shrinking?

#196

Post by socceroos »

throwaway946513 wrote: post #181
wiz21c wrote: post #154

Earlier quoted context omitted.

after a hard burn out I can assure you I saw that my brain actually left my skull (and is now tiny far away on the horizon)

It's been pulled by the event horizon.

Surely it's been pulled by what is beyond the event horizon, not the event horizon itself.

Re: Why are our brains shrinking?

#197

Post by raattgift »

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…

Please teach them how to make durable records!

Re: Why are our brains shrinking?

#198

Post by notriddle »

exporectomy wrote: post #94
notriddle wrote: post #85

Earlier quoted context omitted.

Same reason so many people object to censorship: nobody can be trusted with that kind of power.

Is that really why eugenics is demonized? That the human race (not any living individuals) is giving up its freedom to some sort of fallible authority? I guess, like censorship, people only object to an arbitrary subset of it. People love censorship of "really bad" ideas just as they love eugenics of "really bad" genes. Most people seem happy with asserting our authority of gene selection over animals though :P Conse…

People select their own mates. On the assumption that you aren’t just advocating for stuff that’s always happening, you presumably want to set up some authority for who people mate with other than the couples involved. Why can’t they decide for themselves?

It really is pretty similar to the kinds of things that are used to advocate against E2E encryption. An attempt to have the state encroach on territory that used to be private.

Re: Why are our brains shrinking?

#199

Post by vlovich123 »

matheusmoreira wrote: post #188
vlovich123 wrote: post #179

Earlier quoted context omitted.

By what metric are you making the claim that humanity does not reproduce? To my eye we’ve simply unlocked medical science and have taken control of reproduction to the point where it’s not critical to the species for everyone to reproduce. I’d be more concerned about all the plastics and chemicals that are now circulating in our bodies slowly decreasing our ability to reproduce than us as a species being too dumb to…

> By what metric are you making the claim that humanity does not reproduce? I'm not. I was replying to the following question: > What if there's a level of intelligence above which humans decide not to reproduce? It seems obvious to me that a species that drives itself to extinction cannot be considered intelligent. Doubly so if it does that due to lack of reproduction. > it’s not critical to the species for everyone…

> It is. Every couple must have a certain amount of children in order to simply maintain a stable population.

On average. That doesn't mean that every single couple needs to reproduce. In fact, historically, that's certainly not been the case because some couples are just incapable while others reproduce far more than the average.

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