Evolution of the Human Mind: Understanding Brain Development Over Time

[PeterDonis]

What I am contending is that HOW people think has changed.

And whether this is true (I think it is), and to what extent, and what it means, and all the details related to that, isn't a question of biology; it's a question belonging to some other discipline (such as cognitive science, as I suggested before). Which means it's off topic for this thread and this forum. The original question of this thread was whether the brain itself, its raw biological capacity, has changed; it looks like you have gotten enough feedback on that question. If that's true, then this thread has probably run its course. The question of "how people think", considered apart from how brains have or have not changed biologically, belongs in a separate thread in the appropriate forum.

 

[Ygggdrasil]

What I am contending is that HOW people think has changed.

I'd agree with PeterDonis that this question is beyond the scope of biology. However, I will point out this study that may be relevant to this question:
http://news.sciencemag.org/archaeol...ay-have-evolved-help-our-ancestors-make-tools

 

[Mark44]

There are some excellent comments here for me to read and digest further. I thank those who have contributed so far, you have given me some excellent food for thought as well as a lot of further reading.

Mark44 and PeterDonis, the difficulty here is my effort to explain what I am thinking. I do realize my take on this is in all likelihood wrong, but at this stage you haven't shown me whether that is the case because I haven't made my argument clearly. I'll have nother quick stab at it.

For myself, your argument has seemed clear to me, but what's not clear is on what evidence you base your argument/opinion.

I assume that a brain of 20,000 years ago is the same as one from today. That has been largely confirmed by most here though DiracPool's comments suggest otherwise. But for the sake of discussion let's agree that an ancient braqin (20,000 years ago) is likely to be the same as today.

I completely agree that a man of today dropped 20,000 years ago would struggle to survive, if this really happened. For all sorts of reasons including that the locals might simply dispatch him. I also agree that the brain of 20,000 years ago has the same capacity or potential as one of today.

What I am contending is that HOW people think has changed. Yes knowledge has accumulated, but knowledge is useless without a means to apply it. An engineer, or a quantum physicist, must learn both the facts, and the methods for applying those. Teaching techniques have developed over time as we establish better ways to educate. And allied with this is the development of more complex language and other symbolic means to codify complex ideas and relationships, for example mathematics.

I imagine, without knowing what science may say, that a 40 year old brain has set up a pattern of internal connections and representations that are fairly 'fixed'. That is, once you've been taught what and how to think (and I mean this both in terms of specific skills and knowledge as well as more general matters of social relationships and behaviours), it is not easy to make major changes to those. Sort of like old dogs and new tricks.

A person of ancient times would have a way of thinking that has been set by his time. He would know far fewer actual facts and he would have quite limited ways to apply those facts.

I'm not sure that I agree with "far fewer facts" and "quite limited ways to apply those facts." On what do you base this conclusion? As a counter to your claim of "far fewer facts," and using Aleut and Eskimo cultures as a proxy for early mankind, my limited knowledge of their languages is that they had 15+ distinct words for snow, which suggests a pretty sophisticated understanding of their environment, not to mention that these societies were able to make a living for thousands of years in an environment that none of us participating in this discussion would be able to survive for more than a day or two.

I think the further back we go, the more limited would be his abilities in this respect. Once we get back to when language had not developed, I imagine his thinking would have been quite rudimentary by today's standards.

Regardless of how the brain is structured or whether it has changed appreciably in the past 50,000 years, it is language that allows us to introspect in more complex ways. It allows us to do complex analytical thinking, it permits us to share knowledge and pass it on, and it enables a greater level of shared understanding and cooperation.

Thus, a modern man with a more developed mind would, if placed in the distant past and given the support to learn local skills and knowledge, be able to do so. I think he may not be able to grasp the nuances of local social customs, but I think he should be able to learn all known facts and apply those.

Again, based on what evidence? What you're calling "nuances" I am arguing would be incorrect answers in the pass/fail exam of life. I have questioned your thinking in some of my previous replies, none of which you have replied to. Why do you believe that a modern man would be able to learn "all known facts" and apply them? Please back up your claims with some evidence.

I have given reasons for why I believe this is not plausible, based on the evident ability of those early people to survive in a harsh environment, and the equally evident inability of modern people to survive outside of civilization.

My take on your claims is that you place very little significance on what early mankind had to know to survive, such as what plants could be eaten or used for medicine, how to capture or kill animals for food, how to make clothing, how to make shelters, and many other skills. Do you know how to do any of these things? I would consider your opinion more valid if you were speaking from experience. On the other hand, if someone has no knowledge of, or appreciation of the difficulty of these skills, it is very easy to describe them as easily learned.

I do not think an ancient person brought into today could do so. But I aghree that 1 or 100000 babies from then raised today should display equal cognitive abilities as a modern person.

I think the mind has developed, or evolved, over time. Which in a mechanical sense means that the brain's processing capacity, while unchanged, is utilised in more complex ways. In a clumsy analogy, I mean that it is like a powerful computer that in the past was used to run a simple program while today it runs a more complex program.

Not a good metaphor. Assuming we're talking about the same computer, it would have the same instruction set then and now, so it would not be able to run a more complex program now.

However, there is one curious wrinkle to that idea which I think might be sensitive to discuss. I think what holds true due to time, also holds true today.

A question that @berkeman asked earlier is: what is your motivation here?

 

[Graeme M]

I agree that this has now strayed to a field outside the scope of biology. The original question was around the extent to which the brain had evolved over time, in particular whether it had changed substantially recently (being around the last 10-20,000 years). My specific interest is more to do with cognition I think, and this question was more to set the scene for further inquiry. My best guess based on what I'd read was that the brain hadn't changed much and that the potential to do what people do today had existed in distant times. Notwithstanding DiracPools comments, which I will follow up on, it seems that is the case.

For my purposes of learning about the mind and cognition, the basic fact is that an ancient brain (circa 20,000 years ago) is the same as a modern brain, as best we know.

Mark44, a part of the problem here is my use of language. When I say I "think" something, or venture an opinion, I am simply stating what my own consideration suggests to me. I don't know if I am right or wrong. Nor do I have a specific axe to grind, although I think I do have some broad idea in mind. My motivation is simply that I am interested in how the human mind works and why it might differ from that of another species. I have come at this with absolutely no knowledge beyond some high school biology and a few books I've read in the past. It's just a subject of interest, I don't think I am trying to defend a particular position.

My broad idea is that I think a modern mind is a more complex thing than an ancient mind. I don't think it makes sense to say that 'knowledge' has increased. What is knowledge? Is it just facts, or is it the way in which the mind makes use of those facts? I think, with no evidence beyond my own observations, that being able to know what plants to eat, or how to kill an animal, is a relatively simple set of skills.

By the way, I'm not specifically talking about any old Joe Average. I am more getting at the capability of the mind to grapple with complex ideas and develop new models of the world and how that filters down to Joe Average. Perhaps the words knowledge and mind are synonymous in this context, but I think there is a distinction. A modern mind does more in that sense than an ancient mind. That's my thinking on it, not a stated fact.

Think of it like this. If an astronomer were asked to learn all the facts available to an ancient - how to build a boat, how to cook food, how to worship a god, how to make a spear, how to track an animal - could he do it? With say an intensive 12 month course, with appropriate tutors and hands on experience and so on, could he do it? I suggest he could do a pretty fair job of it. He may not acquire the skills well enough in that time, but I think he would essentially understand the details and the processes. But could an ancient man be placed in a modern context, and with 12 months education make any sort of reasonable fist of any modern undertaking - eg cosmology, surgery, neuroscience? I suspect not. But again, that's just my thinking, I'm not saying it is so. I will have to read and inquire more into this side of things.

 

[AlephNumbers]

with 12 months education make any sort of reasonable fist of any modern undertaking

Of course not, that is absolutely ridiculous! The amount of education needed to understand neuroscience cannot possibly be compressed into a 12 month course. One needs to have a solid foundation in many other subjects- biology, the English language, chemistry, to name a few.

 

[Evo]

Think of it like this. If an astronomer were asked to learn all the facts available to an ancient - how to build a boat, how to cook food, how to worship a god, how to make a spear, how to track an animal - could he do it? With say an intensive 12 month course, with appropriate tutors and hands on experience and so on, could he do it? I suggest he could do a pretty fair job of it. He may not acquire the skills well enough in that time, but I think he would essentially understand the details and the processes. But could an ancient man be placed in a modern context, and with 12 months education make any sort of reasonable fist of any modern undertaking - eg cosmology, surgery, neuroscience? I suspect not. But again, that's just my thinking, I'm not saying it is so. I will have to read and inquire more into this side of things.

Could a modern adult man, with no previous education, given 12 months, make any sort of reasonable "fist" (your word, I have no idea what you meant) of any modern undertaking - eg cosmology, surgery, neuroscience? I suspect not. What you are comparing makes no sense. The astronomer didn't learn what he knows in only 12 months. He's had a lifetime of learning. Do you see your error in thinking here?

If you took a newborn from 10-20k years aqo and raised him in today's society and educational system, he'd have the same abilities to learn as a modern infant.

Edit, I see AlephNumbers beat me to it.

 

[Graeme M]

Evo, Aleph, the concept I am trying to express isn't coming through. I am not making sense to you, but perhaps the concept I have in mind is not sensible either (or so trivial that you haven't considered it). I will have another go in my lunch break, but I accept I am beyond the scope of this forum in doing so. if you wish to indulge me further I appreciate it, if not that's fine.

 

[Mark44]

By the way, I'm not specifically talking about any old Joe Average. I am more getting at the capability of the mind to grapple with complex ideas and develop new models of the world and how that filters down to Joe Average. Perhaps the words knowledge and mind are synonymous in this context, but I think there is a distinction. A modern mind does more in that sense than an ancient mind. That's my thinking on it, not a stated fact.

Think of it like this. If an astronomer were asked to learn all the facts available to an ancient - how to build a boat, how to cook food, how to worship a god, how to make a spear, how to track an animal - could he do it? With say an intensive 12 month course, with appropriate tutors and hands on experience and so on, could he do it? I suggest he could do a pretty fair job of it.

We'll have to disagree on this, I guess, but my answer would range from a flat "No" to "Probably not." Stephen Hawking counts as an astronomer, no? I don't think he would last one month, let alone twelve.

Your hypothesis here is somewhat akin to saying "If I had wings, then I could fly." First off I don't have wings, so this syllogism also doesn't fly. As for "all the facts available to an ancient" - the hypothetical interloper wouldn't just stroll down to the library and pick up a book conveniently titled "Compendium of All Known Facts." There would not be any central repository for these facts.

There's no guarantee that any people the modern man meets would greet him with open arms to share their hard-earned knowledge. In fact, if he were to alight in one of many places on Earth even as recent as 100 to 200 years ago, the people he met would be more likely to kill him and eat him than to share their hard-earned knowledge with him. After all, he isn't in their family or their clan, so he's fair game.

Have you ever built anything with your own hands? Built a fire without using matches? Caught a fish? Found your way in a place with no roads or trails? Built an igloo during a snowstorm? Please correct me if I'm wrong here, but you seem to assume that these are relatively trivial tasks that any intelligent person could perform, and that said person could learn "all available facts" in a short time. To me, and again, correct me if I'm wrong, this sounds like it comes from someone with little or no knowledge of the difficulty of these undertakings.

He may not acquire the skills well enough in that time, but I think he would essentially understand the details and the processes. But could an ancient man be placed in a modern context, and with 12 months education make any sort of reasonable fist of any modern undertaking - eg cosmology, surgery, neuroscience? I suspect not. But again, that's just my thinking, I'm not saying it is so. I will have to read and inquire more into this side of things.

 

[PeterDonis]

At this point the original question of the thread has been answered, and we are straying far beyond biology. Thread closed.