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Why are our brains shrinking?

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131–140 of 199 posts

Re: Why are our brains shrinking?

#131
post #44

Earlier quoted context omitted.

I definitely move through life seemingly in a mechanical fashion. I suspect in the wild I would be alert, all attention, always anticipating, planning.

in the wild I would be alert I am when I hike alone. Not super alert - since there are few dangerous animals in my country - but alert still. Also, you are very alert when you walk in bad neighbourhoods.

You mean bad neighbourhoods like Wall Street in NYC? :D

Re: Why are our brains shrinking?

#132

Earlier quoted context omitted.

From the article it indicates this shrinkage began 70K years ago, or 65K years before writing. In addition, vast majority of the population didn't know how to read or write until 100-150 years ago.

Maybe it’s just language in general. If I’m in a tribe with 100 people, and we all know to talk, not everyone needs to remember every single thing you might ever need. If you forget something, you can ask around, and probably someone remembers.

On the contrary, we create more abstractions and complexity from more people which create more complex social dynamics, more inventions, words, ideas, etc. In addition, tribes were not so static in Pre-agricultural eras. Tribes would regularly trade or swap members, and some would grow or collapse entirely.

Re: Why are our brains shrinking?

#133
It seems that now we use around 10% of the brain power. Maybe we were optimizing for energy consumption?

Until the second half of the last century it was hard for the majority of people to find enough food.

I would expect that our brain will start to grow slowly if food won't be a problem for a long period. The same way our bodies started to grow once we had enough food.

Re: Why are our brains shrinking?

#134

Earlier quoted context omitted.

From the article it indicates this shrinkage began 70K years ago, or 65K years before writing. In addition, vast majority of the population didn't know how to read or write until 100-150 years ago.

I definitely move through life seemingly in a mechanical fashion. I suspect in the wild I would be alert, all attention, always anticipating, planning.

Only habitual things that you've already learned are done so mechanically. But you've already learned magnitudes more than your ice age ancestors as well as your pre-industrial and pre-information age ancestors. You've flexed parts of your brain and had to use more abstract knowledge than they ever had to.

I suspect that some other factor is responsible for the shrinkage. It could just be pure sexual selection. Maybe we find smaller more symmetrical heads to be more attractive and we sexually selected for them over tens of thousands of years. Also could be responsible for domesticated animal brain shrinkage, as we select for more attractive animals.

Could it be true that our brains got more complex even as they got smaller or did we legitimately lose some IQ points from the shrinkage?

Re: Why are our brains shrinking?

#136

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…

Clearly they mean that TikTok is so bad it's actually shrunken our ancestors' brains posthumously.

Re: Why are our brains shrinking?

#137

Earlier quoted context omitted.

I wish I could upvote this more. I would be willing to bet a number of such comments did not even read the article and responding based on impulse with their gripe about modern society du-jour.

The HN rule about not being able to ask if someone read the article or imply/suggest that they did not is the worst rule on the site, because it encourages this behaviour :(

HN needs a lot of rule changes. The narrative of "dang is a great mod" and "HNs rules are actually great" flys in the face of repeated examples of complete incompetence/corruption within HN and it's moderation practices. (E.g. calling discussion about political topics dang doesn't like "ideological flame bait" and deleting the posts.)

Re: Why are our brains shrinking?

#138

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…

Clearly they mean that TikTok is so bad it's actually shrunken our ancestors' brains posthumously.

I think you meant retroactively.

Re: Why are our brains shrinking?

#139

Although our brains were getting bigger progressively, around 70,000 years ago they plateaued, and have been shrinking ever since. John Hawks, an anthropologist at the University of Wisconsin, explains how, over the last 20,000 years alone, human brains have shrunk from 1,500 cubic centimeters (cc) to 1,350 cc, roughly the size of a tennis ball. Except this requires extrapolating brain volume from the skull , which p…

Yes, exactly. I would say the error in measuring brain size over a 70,000 year period is sure to be at least 20%.

Re: Why are our brains shrinking?

#140

Earlier quoted context omitted.

I wish I could upvote this more. I would be willing to bet a number of such comments did not even read the article and responding based on impulse with their gripe about modern society du-jour.

The HN rule about not being able to ask if someone read the article or imply/suggest that they did not is the worst rule on the site, because it encourages this behaviour :(

Well, you can still point it out by starting your reply with "The article clearly states that [...]"

It's the offensive part that's not encouraged here - and I dig that.

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