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The human brain grew as a result of the extinction of large animals: new paper

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Re: The human brain grew as a result of the extinction of large animals: new paper

#61

This line of thinking falls into a common issue I have with evo-psych work. The paper proposes a mechanism that could select for intelligence, but doesn't provide evidence that the mechanism caused humans to evolve to be intelligent. It's the equivalent of the "Is-Ought" fallacy for empirical sciences.

I agree with your criticism. Still, I'm trying to figure out exactly what my issue is with evo-psych claims that I don't have with e.g. physics claims. There seem to be some commonalities between the two fields: developing models to explain empirical data. And when working with their models, they're willing to assume a certain degree of causality. I wonder if my issue is that evo-psych is a lot more like history than…

> Still, I'm trying to figure out exactly what my issue is with evo-psych claims that I don't have with e.g. physics claims.

Can you give an example of an analogous claim in physics that you have an easier time accepting?

Not flaming. Just trying to understand a similar situation that might arise from physics.

One of the main issues I have with evo-psych is that you can't run rigorous control experiments, so my "analysis" of the claims amounts to "Well, that seems like a reasonable explanation. But so do a hundred other models...."

Re: The human brain grew as a result of the extinction of large animals: new paper

#63

I believe that the series of extinctions that cleared the way for (and perhaps necessitated) the rise of intelligence in apes was the great filter . I can't ignore global warming as another possible filter, but I think the big one is behind us.

Assuming there is only one big filter, which I think is unlikely. Any mega black swan event is a filter in its own since it's disturbing the system you are adapted to. The worse event is one that disturbs the system you are dependant on. Climat change is terrible, but it could be worse. We depend on oxygen. Gravity. What else await for us ?

If you define a great filter as something that statistically prevents the preponderance of life in the galaxy, then "any mega black swan even" is just noise. With small likelihood, it will wipe out a civilization, (definition of black swan). But for it to be a great filter per definition, it has to somewhat reliably affect all potentially universe-spanning intelligence. All I'm saying is that most likely, once an intelligent tribe of creates arises, it's likely to go on to dominate the planet, and likely to go on to reach technological readiness to go to space (assuming it can get access to energy easily, which may be another small filter).

So, you're not wrong, all dangers events could be humanity's end, I'm just saying something more general -- that civilization-limiting events are probably clustered before the civilization arises.

Re: The human brain grew as a result of the extinction of large animals: new paper

#64

I believe that the series of extinctions that cleared the way for (and perhaps necessitated) the rise of intelligence in apes was the great filter . I can't ignore global warming as another possible filter, but I think the big one is behind us.

This is, at the very least, an interesting though experiment.

We often suppose:

  (we can't find intelligent extraterrestrials)⊃(there is a great filter ahead of us)
But what if:

  (we have passed a great filter)⊃(there aren't many intelligent extraterrestrials)
That doesn't mean there aren't other filters in our future. But it could help explain the Fermi Paradox. It also fits with the apparent dearth of marginally-intelligent and marginally-unintelligent species here on Earth with us.

Re: The human brain grew as a result of the extinction of large animals: new paper

#65
post #27

Earlier quoted context omitted.

Do we really currently use our brains as efficiently as possible? The decrease in size could be the outcome of one of the bottlenecks, like the one 200k years ago.

The problem could be with distribution. In a hunter-gatherer society, all members require this intelligence described in the article. In a hierarchical early agricultural society, only the ruling classes and to an extent middle classes do. Thus you end up with a distribution of intelligence (and brain size) aligned along caste, with a wide range. Who you sample influences your measurements.

Why do you assume that being a subsistence farmer requires less intelligence than being a landlord?

Peasants were poor, not stupid. [1]

Their landlords may have written about them as if they were, but they were hardly unbiased observers.

[1] https://acoup.blog/2020/07/24/collections-bread-how-did-they...

Re: The human brain grew as a result of the extinction of large animals: new paper

#66
post #30
post #21

so with the mass extinction of the honey bee, we'll turn into super geniuses and convert nuclear fusion directly into food.

The supply chain would have a few steps between fusion and food, but if we had fusion powered electricity generation then the end result isn't too far removed from that. Fusion > electricity > hydrogen via hydrolysis > Haber process produced fertilizer > food

[deleted]

Re: The human brain grew as a result of the extinction of large animals: new paper

#67
post #29

This line of thinking falls into a common issue I have with evo-psych work. The paper proposes a mechanism that could select for intelligence, but doesn't provide evidence that the mechanism caused humans to evolve to be intelligent. It's the equivalent of the "Is-Ought" fallacy for empirical sciences.

It is called ad hoc explanation.

Thanks, I didn't know about this: https://en.wikipedia.org/wiki/Ad_hoc_hypothesis

Re: The human brain grew as a result of the extinction of large animals: new paper

#68
post #61

Earlier quoted context omitted.

I agree with your criticism. Still, I'm trying to figure out exactly what my issue is with evo-psych claims that I don't have with e.g. physics claims. There seem to be some commonalities between the two fields: developing models to explain empirical data. And when working with their models, they're willing to assume a certain degree of causality. I wonder if my issue is that evo-psych is a lot more like history than…

> Still, I'm trying to figure out exactly what my issue is with evo-psych claims that I don't have with e.g. physics claims. Can you give an example of an analogous claim in physics that you have an easier time accepting? Not flaming. Just trying to understand a similar situation that might arise from physics. One of the main issues I have with evo-psych is that you can't run rigorous control experiments, so my "anal…

Again, I'm just trying to understand why my BS detector squeals at evo-psych and not physics.

Regarding an example: I was thinking along the lines of physics models that, in daily use, physicists treat as genuinely true. This includes concepts that are somewhat problematic, like true causality. (E.g., Newtonian mechanics as taught in high-school.)

But after some more thought, I think my real issue is how the two communities vet their theories. My simplistic take on it is:

The physics community has a healthy focus on refutability. IIUC, the community has little tolerance for someone even posing an unrefutable theory, let alone espouse it as likely truth.

The evo-psych community (and I could be mistaken) is much more tolerant of people advancing theories that are (practically speaking) untestable as though they were genuinely true.

Re: The human brain grew as a result of the extinction of large animals: new paper

#69
I’m not entirely convinced with their underlying assumption about big vs small animals...

It should be tested.

The authors of the study should try to catch a bear. And then try to catch a mouse. See if there is a correlation to their IQs.

Re: The human brain grew as a result of the extinction of large animals: new paper

#70

Earlier quoted context omitted.

As protohumans and humans invaded lands, they likely extincted megafauna and flora calorie and protein sources that were easiest to access. This then likely required more mental effort and creativity to solve food security problems with hunting and gardening.

It's interesting as it's a common argument that "meat caused us to have big brains, meat good", but that analysis might not be so clear cut. If this paper is right it may be more of the search for meat is what caused our brains to grow and less so meat protein.

It seems nonsensical to me that simply eating meat protein could somehow cause a genetic change leading to great-grandchildren with larger brains.
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