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Comment by weinzierl | Hacker News Reader

I can't help thinking that this is where humanity is heading. Given that the different parts of the brain have to compete for resources and given what the cerebellum does, it makes sense that a lesser developed one can be an advantage: It frees up resources for parts of the brain that are more important in our times.

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Human society provides nowhere enough pressure for evolution to have effect (for good reasons), and our humanity timeline is nowhere near lengthy enough so far either. So I don’t think we are heading anywhere in that regards

Selective reproduction is evolutionary pressure; survival is mere prerequisite.

I agree but on the flip side it is interesting to consider what were the pressures and the timeline to bring us to where we are now.

Great ape brains are distinguished from monkey brains by their larger frontal and cerebellar lobes. The Neanderthals had bigger brains than us but smaller cerebella. And, most strikingly, modern humans have much bigger cerebella than “anatomically modern” Cro-Magnon humans of only 50,000 years ago (but relatively smaller cerebral hemispheres!)

How would you explain increasing average height in the US youth in the last 30 years? It can't be food availability, because 30 years ago people weren't hungry either

Absolutely food, or at most a hormonal change based on food. Possibly with s side-order of lack of a few of the childhood diseases that have been controlled with inoculations. 30 years is WAY too small a timeframe for human evolution. That works on the order of 50-100 generations, not a single generation.

Evolution doesn't happen quickly, but selection does. If something greatly changed how we select partners the past 100 years it could have an effect within a single generation generation. What could that be? Well, maybe feminism so women don't need to rely on a man to provide income, maybe socialist policies so nobody has to go hungry, and so on, plenty of reasons why some genes could be selected out of the gene pool that was previously fine there.

Height stopped increasing around the mid-1970s and has been flat or falling since

https://ourworldindata.org/grapher/average-height-by-year-of...

https://www.dailymail.co.uk/health/article-12868421/american...

Worse for city kids:

https://www.scientificamerican.com/article/rural-children-no...

Lack of disease and disease treatment. Mostly Vaccines. I got sick like 2-3 times grand total growing up, and only once any more than mildly. My parents and their parents all got badly sick more than that growing up, and both have stories about being on deaths door, e.g. my dad got german measels at 17 and was bed ridden for a month; I didn’t get my last growrh spurt until I was 19.

I'm not sure about that. Being unable to anticipate context sounds terrible for pretty much any task. Having to think through every step of anything is terrible. Not being able to form sentences fluently and instead having to arrange them like puzzles is far too time consuming. The article literally is explaining how a large cerebellum is crucial for humans' high intelligence. Reallocating resources to other parts of the brain would make us stupider.

Having no context does allow for a fresh perspective...

Having to think things through slowly step by step may reveal errors other's glossed over...

the cerebellum is important. But maybe, since we really know less about the brain than we think we do, differently wired does not equate 'stupider'. It takes all sorts to make a world.

I agree with the language part, tedious... but maybe in certain situations it might be useful.

I mean yes, people with disabilities often have a unique contribution to offer and a unique perspective. They often excel at very specific things. However, implying that it is so advantageous to be disabled that we would all evolve to be that way is ridiculous. Thinking things through slowly step by step may reveal errors others have glossed over...But it's perfectly possible for someone without a severe disability to do that. Meanwhile, the person with minimal to no cerebellum is totally incapable of stepping up to the task when, like a lot of the time, speed and intuition is important. If I wasn't able to rely on context and intuition at all I wouldn't be able to do my job, or even day to day tasks, with enough efficiency to get anything done. Furthermore, someone without a cerebellum will also have to learn to not smash themselves in the face when they're trying to eat and have to deal with constant sensory processing issues. This is not advantageous. It's a disability. So it's not going to be picked up by natural selection.

The premise that needs to be scrutinized is whether what we are deeming a “disability” is actually that. Thinking in systems, a component’s calibration (whether it is able or not) to a system can change due to the system as a whole changing (political, economic, cultural pressure).

One example is how the change from hunter/gatherer to agricultural lifestyles may have rendered the strengths of the hunter’s brain a weakness in an agricultural society.

The issue is nobody is convincing me that being unable to use context and sensory input properly would be advantageous in our current society. Because it wouldn't. And that's the end of that.

Being unable to anticipate context could reduce the prevalence of stereotyping, for instance.

I imagine it's like performing a task in software ("big" brain, cerebrum) or hardware (cerebellum). One of them is faster and more efficient but very specialized. If it breaks you're left with the task being performed slower and less efficiently on the brain that can execute arbitrary code.

But I can't imagine any change in this split in responsibilities will happen on human relevant timescales. The cerebellum is probably not evolving very fast anyway, while the cerebrum might evolve comparatively faster but it has no pressure to do it. And "faster" still means tens of thousands of years.

Movement is very important to our health. People who don't move as often just die younger than those who don't.

I don't know how it would impact our evolution long term.

Doesn’t matter if you live to 55 or 95 if you have some kids when you’re 25.

I don't think that's correct; raising your kids - and potentially involvement with grandkids! - impacts long term results.

In this same sense, people with no children can still help raise relatives, provide for them, or otherwise contribute for the long term success of their extended family, and thus indirectly spread their genes

What resources does it have to compete for? We basically have unlimited protein and carbs at this point.

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