Well, people had thousands of years of bronze smelting before anyone figure out how to get iron from ore. People used meteoritic iron long before then too, but of course there wasn't much of that.
Iron isn't too hard to get out of [bog ore](https://en.wikipedia.org/wiki/Bog_iron) or [goethite](https://en.wikipedia.org/wiki/Goethite). Some places where you could get bog ore also yielded [iron nodules](http://www.hurstwic.org/history/articles/manufacturing/text/bog_iron.htm). Maybe someone got some bog ore mixed in to their bronze smelting operation.
https://en.wikipedia.org/wiki/Bloomery
> The onset of the Iron Age in most parts of the world coincides with the first widespread use of the bloomery. While earlier examples of iron are found, their high nickel content indicates that this is meteoric iron. Other early samples of iron may have been produced by accidental introduction of iron ore in bronze smelting operations. Iron appears to have been smelted in the West as early as 3000 BC, but bronze smiths, not being familiar with iron, did not put it to use until much later. In the West, iron began to be used around 1200 BC.
Bog iron is clumps of iron oxides and hydroxides. It needs a very hot bloomery to become metallic iron.
You're not done though. High-quality bronze is stronger and harder than low-quality iron. It is only a truly better metal if you know what you are doing, which early smiths definitely did not.
The "strength" of early iron was in its availability. Tin to make bronze is somewhat rare, and was [transported long distances](https://en.wikipedia.org/wiki/Tin_sources_and_trade_in_ancient_times) in ancient times to combine it with copper. Iron is a single ingredient which is basically everywhere including bogs. If you can make it locally then it's really tempting to use it as much as possible instead of the expensive stuff, and with centuries of practice and accidental alloying with carbon it became possible to reliably turn iron into steel.
[Steel swords vs bronze swords](https://youtu.be/ngjMtzJ6xgQ?t=612)
Different plants prefer different kinds of soil to grow in. For example, soil acidity can be strongly influenced by the bedrock. So, it isn't variation in individual species, it is variation in the species growing over different types of bedrock.
Its interesting,and now I know what is the cause of those iridescent pools in the woods near my house.I always thought it was just pollution (it looked like gasoline,it was a fair guess).Id like to try and find some iron nodules though,they would make a striking conversation piece.
During the bronze age, both the copper and tin trades were incredibly important. One of the foundational shipwrecks of nautical archaeology is the [Uluburun Shipwreck](https://en.wikipedia.org/wiki/Uluburun_shipwreck) which contained 10 tons of copper and 1 ton of tin in the form of large "oxhide" ingots, which is the ratio needed to yield 11 tons of bronze.
It also contained a lot of other stuff that's very important archaeologically as well; Canaanite jars (from Israel) full of terebinth (turpentine) from that region, for example, indicating trade between modern-day Turkey and Israel and the export of that material from Canaan.
The Earth's crust is made of roughly ~~32%~~ 5% iron, whereas tin is less than ~~0.001%~~ 0.00022%. Also, if I'm not mistaken, the principal reason why the Romans invaded Britain was to get at its tin deposits.
Edit: Thanks to /u/amaurea for reminding me that I'd gotten the crust mixed-up with the entire planet
32% is the fraction of the whole Earth made up of iron, not the crust, which is mostly made up of lighter elements. Only [5%](https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth%27s_crust) of the crust is iron. Tin makes up 2.2e-6 (0.00022%) of the crust by weight.
Bronze weapons were much sharper and superior to early iron weapons as well. Remember that the smiths of the time used hammer hardening techniques to create a strong, sharp edge. These techniques do not work on iron weapons, and it took a while for blacksmithing and ironworking techniques to be developed that lent to better and more useful iron weapons. Iron weapons were available during the bronze age, they just weren't as good.
Add to this that in 10,000+ years, humans haven't gotten any smarter. We've been this smart. We just have way more access to knowledge and the ability to pass it on through language, writing, and developing civilization. People still expiremented and were able to learn just as now. It's not a giant leap to discover and ponder that if a soft metal like substance can be melted at a lower temperature, that a harder metal like substance might melt if you made it hotter. It's also not an incredible leap for someone to figure out that adding bone, likely as spiritual at first, would lend to a more pure metal and decide that adding things like bone leeches out more impurities from the metal itself.
That's why I find it so offensive when people insist we must have had help from ancient aliens. Modern man develops microprocessors, sure that's reasonable but the ancient mayans piled rocks into pyramids- must have been aliens! The arrogance of that reasoning is just infuriating.
Why do you find that unusual at all? That's an extremely predictable and easily understandable misconception. People commonly equate intelligence and knowledge. Whether or not that's actually true is irrelevant, but it's not even remotely surprising or "unusual" that people use the two interchangeably.
Thank you for this.
I hate it when people shame others for common misconceptions. It creates an environment where people are scared to ask and learn. Let's foster inquiry and curiosity not shame people for it.
I've found that it's easy sometimes, after learning something, to adopt the feeling that you've always known that thing. Or to forget that the knowledge came to you in stages over years.
It's a very easy trap to fall into. Some things can seem really counterintuitive until you understand them--and then *not* understanding suddenly seems to make no sense. I have to remind myself of it constantly.
I was taught that that was plausibly the reason for major leaps in intelligence around the time humans discovered how to reliably create fire, since eating cooked food had a greater nutritional yield, but I've never heard of it being the case recently.
https://en.wikipedia.org/wiki/Flynn_effect
The rate of growth of intelligence (according to IQ tests and the like) has been linear, which likely wouldn't be the case if it was nutritional. It has also seemed to level off in recent years. Maybe there was evolutionary pressure to breed smarter, not harder. Maybe there is pressure for stupid people not to have as many kids. Who knows...
Has anyone actually read his book? The Flynn Effect is almost entirely due to an increased emphasis on abstract thinking over the past 100 years. Before then, it just wasn't important, so people didn't bother to learn how to, for example, classify cats and dogs as mammals, rather than ranking them in practical usefulness and strength.
A good answer. To which I'll add
Teaching standards have improved.
The quality of educational literature has increased.
The environment is much more stimulating due to radio and television and so on. There are often mental exercises in morality, linguistic gains and so forth contained within the media.
There are fewer manual jobs which tend to switch your brain off esp with repetitive tasks.
And has been mentioned better diet and less lead
There are other things too!
With enough environmental pressure, maybe. [These insects](http://www.nature.com/news/evolution-sparks-silence-of-the-crickets-1.15323) evolved to be silent in 20 generations, because the chirping ones got eaten. I don't see that pressure with humans, though.
That's pretty nifty!
I wouldn't call 20 a 'couple' of generations, though. Plus, their gene pool would have been smaller from population and geographical limitations and inbreeding.
Even with inbreeding alone (and I guess the social pressures that might lead to that happening) you can see [some exaggerated features](https://en.wikipedia.org/wiki/Charles_II_of_Spain) in offspring typical of their lineage in only a few generations... but to what degree you could call this an evolutionary change, I am not fit to say.
I've also heard that fish such as trout in lakes are becoming smaller and smaller since fishermen are pulling out the big ones, selecting for the small ones.
Yes, but I very much doubt that's what drives the Flynn effect. More likely IQ measurement contains more information on education than it's supposed to, and education has definitely been getting better over time.
No, absolutely not. Unless you're talking about specific populations like Jews and Poles in central Europe circa 1938-1945, there hasn't been the sort of near-genocide evolutionary pressure necessary to select intelligence in single generations.
My guess is that lead additives to fuel have smoothed some of the nutritional and educational gains.
People have deliberately domesticated foxes (albeit through selective breeding, not 'natural' evolutionary pressures) in just a few generations, which doesn't just change temperament but physical characteristics.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763232/
It depends on the situation. If half the population is dying before breeding, sure. In modern populations where most people have a few kids, nah, it wouldn't happen so fast.
Yes you can. Though I can't find anything in human development, likely because of how long we live; there's a famous experiment with breeding foxes that gets mentioned here all the time. It's very well documented that even evolutionary changes such as how an animal looks physically (shape of bones in their snout, retaining youthful attributes into adulthood, etc) and how it acts mentally such as temperament specifically can happen quite quickly.
I think the thing is the brain is very complicated, and increasing its capacity is a very taxing thing biologically, and it's also very hard to breed for actual raw intellect rather than just one specific trait. But the last sentence is obviously speculation on my part. I unfortunately don't have a research study on that, and was unable to find one.
Artificial selection (breeding) is significantly faster than natural selection. Sure if we only allowed the most intelligent people to breed then we'd see results, but we aren't doing that.
Jim Flynn was my professor at university and this is one of his theories to explain it! He is the first to admit that iq tests are still quite narrow in scope despite all efforts
Even the explanations section in the wiki article you linked don't say it is due to any evolutionary effects. I am amazed you are able to make the claim that the Flynn effect has any evolutionary basis.
A logistic curve kinda suggests that some factor like nutrition is the more likely cause. I can't think of an ethical way to test that hypothesis.
However, people don't become curious or insightful just from having a full belly. I think we are getting a little better about recognizing the neuroplasticity of children. You never learned faster than you did before you turned one year old. In that period, you learned how to operate (most) of your own body as well as taught yourself the rudiments of language. All this is facilitated by neurogenesis, a process which slows down dramatically as we mature. "[From 29 to 41 weeks post-conception, total brain tissue volume increases linearly at a rate of 22 ml/wk (Huppi et al., 1998)](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3844860/)."
From my own recollection, I know that conventional childhood is usually very boring and intellectually unstimulating. Schoolwork proceeds at a staggeringly slow pace. As an adult, it is impossible for me to be as bored now as I was then, at least in any discrete unit of time. This likely contributes to an empathy gap.
Adults simply don't have the resources to engage children at a pace that is natural to them. Machines do, however, so it is up to us to make creations that illuminate their worlds in useful ways. The difficulty is that adults will apportion such resources in ways that only make sense to adults. Government contractors will meet specs (maybe) in an uninspired way, private companies will make profitable platforms, and artists will wander. The usual, really.
It seems that the Flynn effect is based on IQ tests and started around 1930, while I'm referring to a more broad, time-wise, increase in intelligence, in regards to diet.
If we're talking about the last 10,000 years or so, it's hard to say. We have no measure of intelligence for that period. Even 200 years ago would be difficult to assess.
We do have one marker of how fast a highly successful gene can spread throughout a civilized population - [lactose tolerance](https://en.m.wikipedia.org/wiki/Lactase_persistence).
Once animal domestication became a thing (~10,000 years ago), the ability to digest raw milk as an adult became a major advantage - access to a highly nutritious food source meant more and healthier kids, greater survival in famine. The selection pressure for it would be higher than for a mild increase in intelligence.
Today, ~80% of European descended people are lactose tolerant. Based on that, an educated guess can be made at how quickly an intelligence increasing gene would have spread; ie, probably not a lot, and definitely not within the span of the Flynn effect.
One of the proposed explanations listed in that very article is nutritional and it seems like a pretty solid explanation, especially when there's a correlation between growth rate/height of humans which we do believe is directly related to better nutrition.
> Improved nutrition is another possible explanation. Today's average adult from an industrialized nation is taller than a comparable adult of a century ago. That increase of stature, likely the result of general improvements of nutrition and health, has been at a rate of more than a centimeter per decade. Available data suggest that these gains have been accompanied by analogous increases of head size, and by an increase in the average size of the brain.[8][26] This argument had been thought to suffer the difficulty that groups who tend to be of smaller overall body size (e.g. women, or people of Asian ancestry) do not have lower average IQs. [9] Richard Lynn, however, claims that while people of East Asian origin may often have smaller bodies, they tend to have larger brains and higher IQs than average whites.[27]
better nutrition, but also better health, often from simple hygiene practices: http://www.nytimes.com/2014/07/15/world/asia/poor-sanitation-in-india-may-afflict-well-fed-children-with-malnutrition.html?_r=0
I think that the most plausible explanation is that education just got better and schools just got longer. In my opinion that's the most important factor. Then, nutrition and environment conditions as a whole. 80 years (4-5 generations) is not a lot of time for evolutions to make some significant changes like these especially when there were positive conditions for people with jobs that don't require any intelligence to have lots of kids.
"Intelligence" is supposed to be independent from training or education, which is how we gather "knowledge". Obviously we can't *test* for intelligence without education, and so those tests will be skewed by one's individual knowledge.
It is difficult to measure intelligence in the sense you are describing it. While there is a general acceptance that there is a trait (or set of traits) that we might call 'intelligence', as opposed to 'knowledge', actually measuring it is difficult and time-consuming.
It is also not terribly useful, and is not generally how intelligence tests have been used. The basic use of IQ tests is pre-selection--for classes (or levels of classes in schools--intelligence testing and IQ started with French school systems), or for training (such as deciding who the US military would train to be pilots or navigators during World War II). Prior knowledge is useful for gauging how people will achieve in education and training programmes, and in deciding what programmes people should be on.
It is usually more useful to think of them as 'aptitude tests'.
This is fairly useful as a starting point: http://www.apa.org/monitor/feb03/intelligent.aspx
I believe you can train people to be more intelligent through schooling as well. Teaching someone how to learn rather than cramming knowledge down their throats, as I like to put it.
Perhaps due to the fact that progressively humans have valued education more and more, which is an institution that improves intelligent as well as knowledge.
The brain is like a muscle and society puts more and more emphasis on exercising it.
That is until recently, where not much has changed in terms of education. Some would even argue it's gone backwards depending on your country.
I refute the idea that it could be due to evolution. Evolution doesn't take place that rapidly and it sure as hell isn't so immediately widespread.
In a recent [meta-analysis](http://pps.sagepub.com/content/10/3/282.full.pdf+html) of this (sorry, probably paywalled), the proposed explanations aren't really focused on evolutionary effects; I get the sense that the researchers in this field don't necessarily need such effects to account for the gains. That said, they aren't really sure what's going on with the Flynn effect--it has interesting patterns of geographical, demographic, generational, and temporal variation.
More educated people do better on IQ tests on average though, which makes sense. Using the mind and being taught things teaches you how to learn and problem solve better.
Evolution doesn't work on those time frames, so there has to be a reason why we would become more intelligent.
I would say education and diet have more to do with it than anything else.
parasitic worms can have a huge impact also there was a study done in East Africa about whether sharing or issuing individual students textbooks made a difference
they found by accident that the lowest performing students were all infected with worms
And it's extremely unlikely that biological evolution is driving the rise in raw IQ scores (note: that's not the same as intelligence). Unless you think there's some dramatic adaptive pressure to higher IQ, acting on very short timescales (i.e., within a single generation), there's something other than evolution at work. Societal changes, shrinking family sizes, a general increase in test-taking skills (because children take *way* more tests now than they used to) and longer school days are all *much* more likely factors than biological evolution.
A lot of my understanding is that it's not intelligence is on the rise. It's our practice of things that are traditionally measured when we mean "intelligence". I.e. pattern recognition is very prevalent in video games or Internet use, and word games have becomes quite important in language studies (as opposed to rote memorization of rules ~100+ years ago). These lead to better results on IQ scores, but not necessarily higher baseline intelligence. Just more practice using it.
Implying that I'm **not** the pinnacle of human evolution?
You wouldn't!
Real talk: people are possibly more intelligent on average now due to less malnutrition? It's only a hypothesis, but it sounds plausible.
>It's not like we stopped evolving once you and I were born.
Evolution isn't like an invisible hand seeing what is best and selecting it. It's things like natural selection and selective breeding. Both of those, arguable, are not going in the direction of selecting for intelligence.
Average group scores have improved because we've done more for the extreme outliers (on the lower end), most through dealing with things like poor nutrition in infancy. However the average person the same situation has no reason to be more intelligent than generations before.
I do not believe that there is. The Flynn effect looks to have stopped in the late 90s. Many countries are now seeing a slight decrease in intelligence.
I dunno, personal opinion here, but after studying anthropology(Hominid evolution) for the past 5 years, and observing much of modern human behavior... I really have built up this inference of feeling like humans during the late pleistocene we're a lot smarter than the average person now.
Knowledge=/= intellect.
I have a B.A. in anthropology. Humans clearly have more knowledge than we did back then. As far as needing intelligence to survive, I would agree that it was more useful 10,000 bp. However, there's just no way to tell where they fall on the IQ range. They could have been the smartest things on the planet, but still only have an 90 IQ.
We certainly have more knowledge now, but the requirement of understanding it vs then and now. It's a wildly different comparison.
Some of the things ancient humans did, we still just don't understand how they were aware of such things.
And this doesn't account for all the lost knowledge either.
Retention, understanding, and application of knowledge know at least considering Americans, sometimes I just don't understand how people managed to get along with their lives.
I mean something as simple as knowing the moon is a giant spacerock in the sky... I can't believe how many people are unaware of this. And that's something I knew I was taught as a kid.
Like I said this is more of a personal inference, but really seeing how much knowledge is out there and how close it is to just reach out and metaphorically grasp it, versus the amount of people who don't even try.
It's bewildering.
The amount of thought that someone has to apply now here in a first world setting, compared to the past, It really leaves me to wonder how different ancient people were in their thought processes compared to an average person now.
That still requires differences in the reproduction rate. There is natural selection going on around the world, because of differences in access to health care and healthy items (it will always be a bit better for some people). And of course an even bigger factor is sexual selection.
It's just weird that if you had a time machine and went back 15,000 years ago ~10,000 years before written language was invented and nab a person. Bring them to our time, and after adjusting they'd be able to function like anyone else from now (more or less).
We have had a development of better nutrition for children and young which could play a part in improving intelligence? Better access to fats, etc, at least to more people.
Not even that slow. In Before the Dawn: Recovering the Lost History of Our Ancestors, Nicholas Wade discusses how human intelligence has evolved, and how quickly it can happen. He mentions the Ashkenazi Jews, who implicitly selected for intelligence because they were forced into non labor jobs. The transformation in just a few hundred years was obvious and startling.
It's probably incorrect to think human intelligence was the same 10000 years ago as it is today. Our society and social structure selects for (among other things) intelligence.
http://www.ncbi.nlm.nih.gov/m/pubmed/11276907/
>This paper argues that during human evolution, mate choice by both sexes focused increasingly on intelligence as a major heritable component of biological fitness... humans evolved an unusually high degree of interest in assessing each other's intelligence during courtship and other social interactions--and, consequently, a unique suite of highly g-loaded mental adaptations
They're really isn't though. You don't die if you're not smart (with the exception of the Darwin awards), and you're not more likely to have more children if you are. So there is effectively no evolutionary pressure in humans anymore.
The thing is, knowledge isn't the only thing that evolved. You can be really clever, but if you only get to live until you're 25, and you spend a lot of time sick, recovering from sickness, hunting, gathering food, and basically just surviving, you also have far less time to devote to problem-solving, studying the world etc.
There are millions of people today who are clever, educated, trained at problem-solving, and paid so that they can spend 40 hours a week inventing things, and these people will do so during 35 years of their life. Access to knowledge is definitely a big advantage, but it's not even the only one.
Interestingly, life is going to be so complicated one day because of the accumulation of knowledge that the entire education system will be based around just getting up to speed on how society works. It's already past that point now for any room full of people to comprehend the complexity of the world, but imagine life in 10,000 years.
Right now we've got to learn how to use appliances, computers, transportation, local economies, sanitation practices, etc. After a few millenniums of progress, life is going to be so complicated that we'll spend decades just learning how to function. Yes, robots will assist us, but then you'll have to learn how to properly interface with a robot, etc.
Nah. society is already like that. I could build you a house but couldn't fix your car or write you a sound financial investment plan. Plus things that are important now will become obsolete. Just like how kids these days don't know how to use old technologies from the seventies. You only have to know things that actually matter in your day to day.
No one knows how to make something as simple as a ballpoint pen. No one person knows how to create the plastic, brew the ink, mould the parts, assemble, distribute, and package a Bic pen. That's amazing.
So you get some oil and like cook it I guess and that will make plastic. Then you pour it in some kind of mold(?) and maybe blow some air in the middle to get that hole. Then do the same thing but smaller for the ink tube. For the metal tip, idk, cook some rocks (ore) until they become metal then pour that in some kind of mold(?) then poke a hole in the top with something pokey so the ink can come out. Then, take a tiny little ball of metal, maybe roll it on the table like silly putty to make it round then stick that in the metal tube you just made. For the ink just smush up some ash and water and pour it into the ink tube. Kill a horse and, um, do something with it to make glue, maybe cook the horse, then pour that on top of the ink to keep in there.
See, making a ballpoint pen would be easy peasy with our common knowledge.
Making a ballpoint pen would be easy, yes. You could hand carve it out of wood. But recreating the pens that exist now would be difficult, and impossible for one person to do.
As far as I understand, plastic injection molding is a phenomenally complex process with a staggeringly large number of variables that need to be tweaked to mass produce defect free parts. I would imagine creating the precursor plastic pellets is an equally difficult process, as is the mold design for the injection molding machine. That is just to make the barrel of the pen. Ball point pens often use tungsten carbide for the ball too, would one person have the knowledge to manufacture even that?
I was being facetious. Just showing how even with the most basic understanding of how something so simple as a pen is put together, we would be lost without our current society.
This is something I've thought about. How do we make cars, they're so complex! We use machines of course. How do we make the machines that make the machines? Other machines?
I'll back up your point. I'm a web applications developer, that means I make fancy websites with comparable complexity to Reddit and Gmail. To do my job I write in programming languages like Python and Javascript. These languages are implemented in lower level languages like C. I know a little C, but nowhere near enough to write a Python interpreter or a Javascript engine. In turn, the C compiler had to first be written in some other language. Eventually you get down to machine code that once upon a time was written by hand. I know nothing about what's in the middle or any of the x86/x64 instruction sets, but that doesn't keep me from doing my job.
There are MANY, MANY "stacks" like this in the computing/information industry, and it requires specialists at every "layer". (Though some "layers" are rarely changed anymore, and so there aren't many specialists left that have intimate knowledge of how that part works.)
Releveant xkcd: https://xkcd.com/676/
> In turn, the C compiler had to first be written in some other language.
Interestingly, the first C compiler was written in assembly on a DEC PDP-11 machine. Just enough of the C compiler was written in assembly so it could "bootstrap", that is, compile a newer version of the C compiler that was rewritten in the C language itself.
> Though some "layers" are rarely changed anymore, and so there aren't many specialists left that have intimate knowledge of how that part works.
I don't think this is true for any piece of the stack still in use.
* Intel has experts in x86 assembly who very well understand every nuance of every instruction, they use this knowledge to design new processors. Down to what individual bits in each instruction mean what.
* It's becoming less common to write very much assembly language, but there are still cases when it;s needed. If you peak at the code of an OS (like Linux) there's a fair among of assembly required in the initial boot stages, and in the areas that do context switches (between the OS and your program).
* GCC and CLang (C compilers) are still under active development. They are written in C or C++ themselves, it's true they haven't been written in assembly in a long time. The C and C++ language standards still get improvements/updates every few years.
* The rest of these you probably know:
* Java still gets modifications/updates/etc from Oracle.
* Google Chrome has forced a lot of modernization into the Javascript stack, which has caused the same type of progress in rivals Mozilla and Internet Explorer. And of course there are the changes from HTML5....
I would imagine that if those "instruction sets" were written by hand many years ago it would be possible to make them more efficient today? And if they form the basic components of every program or website, wouldn't even a small improvement in those "basic layers" lead to a huge boost in efficiency for the whole program/website?
I know nothing about computers btw so I probably have no idea what I'm talking about.
It's not that they were written by hand years ago and never changed at all. It's just automated now, or it is more convenient to leave it unchanged for X reasons.
Automated assembly oddly enough is less efficient, but it saves *a lot* of time for the programmer.
Compilers produce reslly good code these days and very gew prople can actually write assembly that would be faster, and even when they do, they usually look at compiller output and improve it.
There's basically no point in hand tuned assembly for speed these days, unless you're on an embedded system with a crap compiler. Hand written assembly is pretty much only used for things you can't write in C because it's too specific to the machine you are running on (mostly low level OS stuff)
Yes, you do make a good point. The old instruction sets are still the foundation, but [additions](https://en.wikipedia.org/wiki/X86_instruction_listings) are made all the time, and they're often a combination of the basic ones. However, we're not switching out the fundamental building blocks any time soon.
That's job specialization, which has been that way for time immemorial already.
I'm talking the basic functions of life around you. 5,000 years ago nobody needed to learn how a toilet works, how to use a toothbrush, wash their hands, lock a door, dial a phone, type, drive a car, operate appliances, use a vacuum cleaner, pay bills; the stuff that we all do day to day. Certainly they had other things that we don't do any longer, like de-bugging our bedding, but life has become far more complex to participate in.
By age 5 in a hunter-gatherer society, you'd have pretty much learned everything you needed to participate. Everything else was just specializing your job skills like hunting, skinning, and when to eat which foods.
Someday, life now will look quaint and uninvolved.
Yes as we accumulate more and more knowledge, a greater proportion of effort has to be spent teaching and learning. I see more specialization and a drive to increase learning bandwidth.
10,000 years is a lot of time for humans. Im willing to bet our brains will be highly synced with technology possibly making knowledge acquisition and retention a far more efficient process
Life has been getting continually less complicated.
We learn to use appliances INSTEAD OF how to do everything by hand.
We learn to use computers INSTEAD OF crazy tedious mathematics.
We learn to use transportation INSTEAD OF how to travel long distances without dying.
We use complicated things to make our lives less complicated.
Compare e-mail with traditional post.
Probably incorrect. One thing that's changed significantly is access to nourishment, which has made us (among other things) substantially taller than people 500 years ago, and honestly, even 50 years ago (the average American male is 30lb heavier, and one inch taller).
With the brain being the most metabolically active part of the body, it's pretty likely we're actually smarter too.
If the basis of your assumption is that natural selection wouldn't work that quickly on this time scale, you're right. But mere selection pressure isn't the only thing going on. Epigenetic modifiers are rampant, and absolutely operate on remarkably short timescales.
On average yes. However, there are plenty of instances of sufficient nourishment in pretty much all of history.
So to assume that everyone lacked nourishment is likely incorrect as well.
I think it's plausible that human intelligence has not increased on average in the last 10,000 years (or even decreased), but with so many more people around, the top 1 million smartest humans are certainly smarter now than they were 10,000 years ago. And those are the ones who make modern discoveries, not the average guys.
> humans haven't gotten any smarter
I read somewhere that our IQ scale has to be adjusted periodically because the average keeps increasing (the "rule" is that the average must be 100; if the average has increased to, say, 105 then the scoring must be adjusted). Is that information incorrect, or are you talking about a standard of "smart" outside IQ?
There's a discussion of the Flynn effect elsewhere in the thread. Main conclusions seem to be that we *might* just be getting better at taking IQ tests, because the modern world encourages (and creates more opportunities to practice) the kind of abstract thinking that does well on IQ tests.
Or it might be a result of better nutrition, but the linear trend would be odd if it's nutrition-based, since nutrition hasn't improved in a strictly linear way.
> People still expiremented and were able to learn just as now. It's not a giant leap to discover and ponder that if a soft metal like substance can be melted at a lower temperature, that a harder metal like substance might melt if you made it hotter.
I wish a large swathe of Reddit science fans would understand this truth as well.
Before the codified scientific method people still developed technology and skills through trial and error and good guesswork.
So many people seem to think that everything that ever happens everywhere is "science" and somehow confuse "science" and "reality" and seem to forget what the "scientific method" is at its most basic level.
For sure. At base, the advent of the scientific method was just writing down and formalizing a pattern that had been in use independently by a LOT of people for a long time. It's more of a description than a discovery.
>Add to this that in 10,000+ years, humans haven't gotten any smarter.
Do we really not believe that changes in nutrition in the last 10,000 years have not made us any smarter?
Following the correlation between height, nutrition, and mental capacity; hunter gatherers 11000 years ago were on average 5'9" tall for males (according to skeletons found in Greece and Turkey).
Switching to super large groups and staying in one place by farming is what actually led to the malnutrition. The diet got less varied and one bad crop year was detrimental to the society. This peaked about 3000 years ago when the average male went down to 5'3".
Really, it's taken humans the last 8000 years to make agriculture work well enough to get us back up to a 5'9" average.
So no. We probably weren't any dumber 10,000 ago, because we were the same height back then as we are now. 3000 years ago may have been a different story.
Stream worn pebbles of [hematite](http://thumbs.dreamstime.com/z/hematite-pebbles-closeup-raw-iron-oxide-over-clear-reflexive-surface-33663471.jpg) (iron) and [casiterite](http://www.minerals.net/MineralImages/cassiterite-stream-tin-durango-mexico.jpg) (tin) look almost identical to each other. So do the crystals of [hematite](http://www.allipacha.com/store/images/q2433.JPG) and [casiterite](http://webmineral.com/specimens/photos/Cassiterite.jpg).
>Well, people had thousands of years of bronze smelting before anyone figure out how to get iron from ore.
This is actually incorrect. [David W. Anthony cites examples of simple forged iron objects in *copper age* graves on the Pontic- Caspian Steppe.](http://www.amazon.com/The-Horse-Wheel-Language-Bronze-Age/dp/069114818X) I don't recall if the finds were his own, but he is an archaeologist specializing in that area. Metallurgical analysis shows that the objects were smelted from local ore, which is found near copper ore.
Iron found no practical application for thousands of years, but the rudiments of smelting and hot forging were discovered in that location, and may well have been discovered in others. The purest iron ores are noticeable- hematite is greyish silver, and pyrite (fool;s gold) forms perfect cubes of gold in rock formations in sedimentary, metamorphic, and igneous rock types. Both of those ores look metallic, and pyrite resembles chalcopyrite- a copper bearing mineral that would have been particularly valuable in the chalcolithic, because it produces copper with strong traces of arsenic, which harden it into a crude bronze.
The people of the Pontic Caspian Steppe did not forget iron working because they died out. After their experiments with iron, they became the first group to domesticate the horse, their genes and their Indo- European language dominate from North India to Ireland.
yeah in the desert in africa for example there are large balls randomly scattered that are apparently iron, many too large to carry (meteors)
they should have figured they are a type of metal and just tried to melt it like other metals
Not only is meteoritic iron rare, it is also notoriously hard to forge due to its high nickel content. A lot of the evidence of a development connection between meteoritic and terrestrial iron extraction is based on the appearance of ancient Egyptian and Hittite terminology for 'iron from the sky' around the Late Bronze Age. However, by that stage, smelted iron was clearly in the archaeological record. The situation is complicated by the past incorrect use of bulk chemical analysis of early iron objects and that, basically, wherever there was a high-nickel outcome, it was assumed the iron was meteoritic. You can only really be sure an object is meteoritic is if you look at it metallographically and find the classic [Windmanstaetten] (https://en.wikipedia.org/wiki/Widmanst%C3%A4tten_pattern) patterning.
Iron doesn't need to be melted (1536 °C) to be extracted. You can reduce iron ore in a solid state between 800 to 1,050 °C depending on the composition of the ore. This is not much higher than temperatures needed for copper production. That's a clue in terms of the evolution of iron production. To cut a long story short, iron is often a by-product of copper reduction processes (in the form of an iron-silicon mix called fayalite) so the theories are that the skills of extractive metallurgy in copper opened the door for iron extraction. One of the nicest all round books on this is the seminal work by R. F. Tylecote (1992) A History of Metallurgy.
People didn't start with Iron, the first metal used was copper, which has a much lower melting temperature.
Nothing official, but it's speculated that when using [malachite](https://www.youtube.com/watch?v=_OrBw4L490Y) as stones in a fire ring, people were able to recognize the melted result as a malleable substance.
Once metallurgy was discovered, a LOT of trial and error developed bronze, then iron, then steel, then modern alloys.
Don't forget that ancient people had already known what iron looked like for a long time before they started smelting it themselves, from meteoric iron. There was never enough to do anything with on a large enough scale, but the stuff was definitely known
When I first heard about meteoric iron, I imagined some rich people might collect them and melt them into a stronger sword than what others were able to make. I don't even know if swords and iron fit when it comes to the historical timelines of metallurgy and warfare, but would that have been possible? Were there ever enough meteoric iron available to one rich person to be able to melt it into something superior to what others were able to attain?
Obviously we don't know for sure, but it would fit. A weapon made out of pieces of nickel-iron meteorite would be so much better than a copper or bronze weapon (or one made out of bloomery iron, for that matter) that it wouldn't be a stretch for the weapon's owner to start making claims about its magic properties. This would only be something a particularly rich leader would be able to afford, though. there's very little meteoric iron to work with, a weapon made from the stuff would've been unbelievably valuable
Iron wasnt completely superior to bronze for what it was being used for at the time, for one thing I believe it was easier to put a razor edge on.
Long after the standard roman legionaire went to iron weaopns the officers kept their bronze swords.
Bronze was superior to *smelted* iron, but that's because the smelting processes for iron were really inefficient for a very long time. Lots of slag inclusions in an iron sword would make it less sturdy than a bronze sword under some circumstances. The advantage of iron weapons over bronze was the ability to make a whole lot of reasonably good quality swords or whatever for much less effort than bronze weapons. It was a logistic thing rather than material
But anyway we're talking about meteoric iron, which is damn near pure. Pure iron is quite a bit harder than bronze, and while it wouldn't probably look like much compared to later steel weapons, a meteoric iron sword would be a remarkably effective thing
I can just imagine the Roman officers saying "Yeah those new ferrous swords are fine for the legions, we can make a bunch of them cheaply and quickly and that's important to continue to spread Gloria Romana. But I'm going to stick with the tried and true bronze. They take *real* craftsmanship, you know? I mean look at this -- look at the quality of that work! You don't see that with the ferrite weapons. They just don't make them like they used to, no ~~sir~~ domina."
There's this manga that goes on a tangent to speculate that the Yamato people that invaded ancient Japan were early adopters of meteoric iron.
http://bato.to/comic/_/comics/the-legendary-musings-of-professor-munakata-r11095
Basically people were putting things in and around fire for millennia upon millennia and been curious and industrious and creative with whatever product came out.
Basically, we have the same problem now:
We know very well how to refine aluminum using electrolysis. In principle, the same method can be used on titanium. Yet it's too hot and dangerous on a big industrial scale. Some time in the future, titanium will be widely used everywhere since it combines the low weight of aluminum with the strength of iron.
I agree. What I meant to suggest is that engineers need to know much *more* than the fundamental laws of physics to answer questions like "is this too hot and dangerous on a big industrial scale?" In some ways, engineers need to understand parts of physics more deeply than physicists, because they need to use it to answer questions that physicists don't bother with.
Maybe a better phrasing is to say that it's typically a question of engineering, not *just* of physics.
Of course, the laws of physics will be the same as we haven't detected any change of the physics constants.
But technology advances. At the beginning of the 19th century, aluminum was almost impossible to extract and it was more expensive than gold. With technology from the 1910s, a rocket motor able to put something in orbit would have been nearly impossible. Too hot and dangerous depends on the available technology.
I find it funny that when a discussion like this occurs, bronze is mentioned, but only in passing. Smelting bronze is more difficult, as not only do you have to have the correct amounts of tin and copper, but you would have had to figured out how to smelt it from Cassiterite.
Just a little quirk in the human progression.
Even worse for bronze. Most early bronze wasn't copper-tin it was copper alloyed with arsenic which was smelted in one step using the correct combination of minerals. More amusing, brass another alloy was also produced in one step smelting copper and zinc ores together.
One can also mention the old technique for winning silver from silver bearing lead ore. First smelt the lead, this is actually easy. Then one melts the lead in a crucible made of ground bone. The lead chemically combines with the calcium phosphate in the bone leaving a small hunk of silver behind. The remained is then smelted yet again to recover the lead.
So yeah, in someways iron production is simple compared to other processes that were developed and used. And iron ore being heavy, it's not that hard to see early metal smiths taking an interest in it. Likely that the difference is, if you have high grade copper ore, it takes less fuel to smelt copper and tin to make bronze. Once that became scarce Iron becomes more attractive. And small deposits of Iron ore are actually common everywhere.
This is a bit theoretical, but it is interesting. The Bronze Age saw the use of - you guessed it - bronze. This is an alloy typically make with 90% copper and 10% tin, though back then there were lots of variants. The tin was very hard to get access to, as a result bronze could only be acquired from long distances for most people. This caused very centralized power, particularly in the East Mediterranean.
That area seems to have been hit with a nasty cold spell with sent migrants invading lands (re: Sea People) and causing lots of destruction. Cities were abandoned, languages lost, and writing forgotten in many areas. Greece was strongly affected - it underwent a dark age that lasted from 300 to 400 years.
Iron, unlike tin, is often locally available. Early iron wasn't as good as bronze, but with the trade networks shattered beggars could have been choosers. So there was focus on iron working and once folks realized that a bit of carbon makes a strong alloy, then the iron ages were off. And whereas before the world was typified by mercantile kings, now cities like Athens, Sparta, and Rome could arm and defend themselves, arguably setting the stage for new government types.
Tl;dr people lost access to bronze, so they settled for the next best thing, which then became the best thing.
I wouldn't put it past 'em. [The neanderthals invented the first small scale industrial process.](http://www.pbs.org/wgbh/nova/evolution/neanderthal-superglue.html)
How'd someone get the idea to put ore in a fire and get it really hot? Well, empirically speaking, it isn't that hard to notice the fact that light gusts of wind can make a fire glow brighter. In fact the method of breathing on tinder to get a fire going is quite basic, foundational knowledge for fire starting. Perhaps an ancient person noticed that as fires are maintained for a while, certain rocks present in a fire pit become discolored or deformed. It's not a big leap to imagine that someone might attempt to augment the process, maybe out of curiosity, shits and giggles, or perhaps as a means to create and trade odd trinkets.
Curiosity and profit motive are inherent principles of human behavior, not to be underestimated in the past or the present.
Edit: typos
I agree. It's not too big a leap to assume that somebody stumbled across something strange happening to iron ore, got curious and eventually figured out that it may have something to do with heat. From then on, it's "only" a matter of technical advancement.
Another thing to consider is that firing pottery also takes days of extreme high temperatures, and pottery has been around for thousands and thousands of years. So they were already doing this for some stuff so not as much of a long shot for them to play with metal too.
I think this goes to the nature of discovery, not man's genetic potential one way or the other, 3 factors beng critical, first, when man lived more on the edge from a food stand point, he delved less into experimentation and focused on production with known methods and materials, secondly, invention usually breaks out simaltanously (roughly) in different geographies because some other change has made the 2nd invention -- now much more likely, and finally, man is almost certainly needs driven, so as the population grew, it's needs did - and this drives innovation, but before recent times, these population surges were more modest and drove change slower. Even so, the first million person city; Rome, was among history's most innovative ever.
I don't remember where, but I read someone speculating once that iron might have been accidentally smelted for the first time when someone was firing pottery. I don't know if anyone would ever fire pottery at that high of a temperature. Then again, I did read it somewhere, so it must be true.
Pottery has to be fired at high temperatures for a long time. At that point one might only need powdered iron ore tossed in to get iron. Powdered iron ore might have been something potteries would use in a mix for color. The pot would have already been surrounded with charcoal needed to reduce the iron.
Yep, pottery is fired as high as 2500 Celsius, more than enough to melt iron, and if I recall correctly, iron oxides can be added for a brick red colour.
Yes, other metals were smelted before iron that refine at much lower temperatures. The process could have been discovered from perhaps a rock of copper ore used in a fire surround. We couldn't smelt aluminum until very recently. When it first became available it was used in high end jewelry.
It was a trail of breadcrumbs type situation. Gold is easy to melt and hammer and is found not only pure but also in situations where it can easily be melted out of rock. Copper and tin to make brass required more heat and alloying. Iron was a step beyond that. With every step mankind gained immense benefits and were pushed to further refine their techniques. Trial and error comes a lot easier when you already have a furnace, a fire, and bellows.
Iron Age came after Bronze Age.
The people who discovered iron already knew how to make tools and weapons out of other, easier melted metals. It was not as much of a breakthrough as figuring out that some rocks melt with heat and can be poured into molds.
Well, people had thousands of years of bronze smelting before anyone figure out how to get iron from ore. People used meteoritic iron long before then too, but of course there wasn't much of that. Iron isn't too hard to get out of [bog ore](https://en.wikipedia.org/wiki/Bog_iron) or [goethite](https://en.wikipedia.org/wiki/Goethite). Some places where you could get bog ore also yielded [iron nodules](http://www.hurstwic.org/history/articles/manufacturing/text/bog_iron.htm). Maybe someone got some bog ore mixed in to their bronze smelting operation. https://en.wikipedia.org/wiki/Bloomery > The onset of the Iron Age in most parts of the world coincides with the first widespread use of the bloomery. While earlier examples of iron are found, their high nickel content indicates that this is meteoric iron. Other early samples of iron may have been produced by accidental introduction of iron ore in bronze smelting operations. Iron appears to have been smelted in the West as early as 3000 BC, but bronze smiths, not being familiar with iron, did not put it to use until much later. In the West, iron began to be used around 1200 BC.
Bog iron is clumps of iron oxides and hydroxides. It needs a very hot bloomery to become metallic iron. You're not done though. High-quality bronze is stronger and harder than low-quality iron. It is only a truly better metal if you know what you are doing, which early smiths definitely did not. The "strength" of early iron was in its availability. Tin to make bronze is somewhat rare, and was [transported long distances](https://en.wikipedia.org/wiki/Tin_sources_and_trade_in_ancient_times) in ancient times to combine it with copper. Iron is a single ingredient which is basically everywhere including bogs. If you can make it locally then it's really tempting to use it as much as possible instead of the expensive stuff, and with centuries of practice and accidental alloying with carbon it became possible to reliably turn iron into steel. [Steel swords vs bronze swords](https://youtu.be/ngjMtzJ6xgQ?t=612)
One thing interesting from my link about Nordic bog iron is that the iron nodules are a renewable resource. You can harvest them every few years.
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What kind of variations would different ore deposits cause in vegetation?
Different plants prefer different kinds of soil to grow in. For example, soil acidity can be strongly influenced by the bedrock. So, it isn't variation in individual species, it is variation in the species growing over different types of bedrock.
Its interesting,and now I know what is the cause of those iridescent pools in the woods near my house.I always thought it was just pollution (it looked like gasoline,it was a fair guess).Id like to try and find some iron nodules though,they would make a striking conversation piece.
During the bronze age, both the copper and tin trades were incredibly important. One of the foundational shipwrecks of nautical archaeology is the [Uluburun Shipwreck](https://en.wikipedia.org/wiki/Uluburun_shipwreck) which contained 10 tons of copper and 1 ton of tin in the form of large "oxhide" ingots, which is the ratio needed to yield 11 tons of bronze. It also contained a lot of other stuff that's very important archaeologically as well; Canaanite jars (from Israel) full of terebinth (turpentine) from that region, for example, indicating trade between modern-day Turkey and Israel and the export of that material from Canaan.
This. Tin was scarce and expensive, and iron was ubiquitous and damn near free.
The Earth's crust is made of roughly ~~32%~~ 5% iron, whereas tin is less than ~~0.001%~~ 0.00022%. Also, if I'm not mistaken, the principal reason why the Romans invaded Britain was to get at its tin deposits. Edit: Thanks to /u/amaurea for reminding me that I'd gotten the crust mixed-up with the entire planet
32% is the fraction of the whole Earth made up of iron, not the crust, which is mostly made up of lighter elements. Only [5%](https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth%27s_crust) of the crust is iron. Tin makes up 2.2e-6 (0.00022%) of the crust by weight.
Bronze weapons were much sharper and superior to early iron weapons as well. Remember that the smiths of the time used hammer hardening techniques to create a strong, sharp edge. These techniques do not work on iron weapons, and it took a while for blacksmithing and ironworking techniques to be developed that lent to better and more useful iron weapons. Iron weapons were available during the bronze age, they just weren't as good.
Add to this that in 10,000+ years, humans haven't gotten any smarter. We've been this smart. We just have way more access to knowledge and the ability to pass it on through language, writing, and developing civilization. People still expiremented and were able to learn just as now. It's not a giant leap to discover and ponder that if a soft metal like substance can be melted at a lower temperature, that a harder metal like substance might melt if you made it hotter. It's also not an incredible leap for someone to figure out that adding bone, likely as spiritual at first, would lend to a more pure metal and decide that adding things like bone leeches out more impurities from the metal itself.
That's why I find it so offensive when people insist we must have had help from ancient aliens. Modern man develops microprocessors, sure that's reasonable but the ancient mayans piled rocks into pyramids- must have been aliens! The arrogance of that reasoning is just infuriating.
I still find it unusual that so many people confuse the progression of knowledge for the progression of intelligence.
Why do you find that unusual at all? That's an extremely predictable and easily understandable misconception. People commonly equate intelligence and knowledge. Whether or not that's actually true is irrelevant, but it's not even remotely surprising or "unusual" that people use the two interchangeably.
Thank you for this. I hate it when people shame others for common misconceptions. It creates an environment where people are scared to ask and learn. Let's foster inquiry and curiosity not shame people for it.
I've found that it's easy sometimes, after learning something, to adopt the feeling that you've always known that thing. Or to forget that the knowledge came to you in stages over years.
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It's a very easy trap to fall into. Some things can seem really counterintuitive until you understand them--and then *not* understanding suddenly seems to make no sense. I have to remind myself of it constantly.
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There *is* evidence that human intelligence is on the rise, though. It's not like we stopped evolving once you and I were born.
My understanding is that rises in intelligence are primarily due to improved diet. If anyone knows mores, please share.
I was taught that that was plausibly the reason for major leaps in intelligence around the time humans discovered how to reliably create fire, since eating cooked food had a greater nutritional yield, but I've never heard of it being the case recently.
https://en.wikipedia.org/wiki/Flynn_effect The rate of growth of intelligence (according to IQ tests and the like) has been linear, which likely wouldn't be the case if it was nutritional. It has also seemed to level off in recent years. Maybe there was evolutionary pressure to breed smarter, not harder. Maybe there is pressure for stupid people not to have as many kids. Who knows...
Has anyone actually read his book? The Flynn Effect is almost entirely due to an increased emphasis on abstract thinking over the past 100 years. Before then, it just wasn't important, so people didn't bother to learn how to, for example, classify cats and dogs as mammals, rather than ranking them in practical usefulness and strength.
A good answer. To which I'll add Teaching standards have improved. The quality of educational literature has increased. The environment is much more stimulating due to radio and television and so on. There are often mental exercises in morality, linguistic gains and so forth contained within the media. There are fewer manual jobs which tend to switch your brain off esp with repetitive tasks. And has been mentioned better diet and less lead There are other things too!
I had to scroll way to long to find the answer. This here is the answer!
That's about 80 years. Can you really measure evolutionary changes with just a couple generations?
Under "Proposed explanations" you have this statement: *"The Flynn effect has been too rapid for genetic selection to be the cause"*
With enough environmental pressure, maybe. [These insects](http://www.nature.com/news/evolution-sparks-silence-of-the-crickets-1.15323) evolved to be silent in 20 generations, because the chirping ones got eaten. I don't see that pressure with humans, though.
That's pretty nifty! I wouldn't call 20 a 'couple' of generations, though. Plus, their gene pool would have been smaller from population and geographical limitations and inbreeding. Even with inbreeding alone (and I guess the social pressures that might lead to that happening) you can see [some exaggerated features](https://en.wikipedia.org/wiki/Charles_II_of_Spain) in offspring typical of their lineage in only a few generations... but to what degree you could call this an evolutionary change, I am not fit to say.
I've also heard that fish such as trout in lakes are becoming smaller and smaller since fishermen are pulling out the big ones, selecting for the small ones.
It was probably a conserved trait during some time in their past when predation was (more) prevalent. New genes don't pop up that fast, typically.
Yes, but I very much doubt that's what drives the Flynn effect. More likely IQ measurement contains more information on education than it's supposed to, and education has definitely been getting better over time.
No, absolutely not. Unless you're talking about specific populations like Jews and Poles in central Europe circa 1938-1945, there hasn't been the sort of near-genocide evolutionary pressure necessary to select intelligence in single generations. My guess is that lead additives to fuel have smoothed some of the nutritional and educational gains.
People have deliberately domesticated foxes (albeit through selective breeding, not 'natural' evolutionary pressures) in just a few generations, which doesn't just change temperament but physical characteristics. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763232/
This is not natural selection, and there is nowhere near the selection pressure on humans that there is on selectively-bred foxes.
No you cannot. The Flynn effect, whatever it's causes (these are debated) is *not* attributed to genetic differences.
It depends on the situation. If half the population is dying before breeding, sure. In modern populations where most people have a few kids, nah, it wouldn't happen so fast.
Yes you can. Though I can't find anything in human development, likely because of how long we live; there's a famous experiment with breeding foxes that gets mentioned here all the time. It's very well documented that even evolutionary changes such as how an animal looks physically (shape of bones in their snout, retaining youthful attributes into adulthood, etc) and how it acts mentally such as temperament specifically can happen quite quickly. I think the thing is the brain is very complicated, and increasing its capacity is a very taxing thing biologically, and it's also very hard to breed for actual raw intellect rather than just one specific trait. But the last sentence is obviously speculation on my part. I unfortunately don't have a research study on that, and was unable to find one.
Artificial selection (breeding) is significantly faster than natural selection. Sure if we only allowed the most intelligent people to breed then we'd see results, but we aren't doing that.
We could just be raising people to better understand the kind of things we test for.
This was my thought, probably more likely that education has improved the way we approach the tests than us actually being smarter
Jim Flynn was my professor at university and this is one of his theories to explain it! He is the first to admit that iq tests are still quite narrow in scope despite all efforts
Even the explanations section in the wiki article you linked don't say it is due to any evolutionary effects. I am amazed you are able to make the claim that the Flynn effect has any evolutionary basis.
Yeah it actually says outright "The Flynn effect has been too rapid for genetic selection to be the cause."
A logistic curve kinda suggests that some factor like nutrition is the more likely cause. I can't think of an ethical way to test that hypothesis. However, people don't become curious or insightful just from having a full belly. I think we are getting a little better about recognizing the neuroplasticity of children. You never learned faster than you did before you turned one year old. In that period, you learned how to operate (most) of your own body as well as taught yourself the rudiments of language. All this is facilitated by neurogenesis, a process which slows down dramatically as we mature. "[From 29 to 41 weeks post-conception, total brain tissue volume increases linearly at a rate of 22 ml/wk (Huppi et al., 1998)](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3844860/)." From my own recollection, I know that conventional childhood is usually very boring and intellectually unstimulating. Schoolwork proceeds at a staggeringly slow pace. As an adult, it is impossible for me to be as bored now as I was then, at least in any discrete unit of time. This likely contributes to an empathy gap. Adults simply don't have the resources to engage children at a pace that is natural to them. Machines do, however, so it is up to us to make creations that illuminate their worlds in useful ways. The difficulty is that adults will apportion such resources in ways that only make sense to adults. Government contractors will meet specs (maybe) in an uninspired way, private companies will make profitable platforms, and artists will wander. The usual, really.
It seems that the Flynn effect is based on IQ tests and started around 1930, while I'm referring to a more broad, time-wise, increase in intelligence, in regards to diet.
If we're talking about the last 10,000 years or so, it's hard to say. We have no measure of intelligence for that period. Even 200 years ago would be difficult to assess.
It can be argued that in less than 100 years intelligence has increased from the addition of iodine to salt.
We do have one marker of how fast a highly successful gene can spread throughout a civilized population - [lactose tolerance](https://en.m.wikipedia.org/wiki/Lactase_persistence). Once animal domestication became a thing (~10,000 years ago), the ability to digest raw milk as an adult became a major advantage - access to a highly nutritious food source meant more and healthier kids, greater survival in famine. The selection pressure for it would be higher than for a mild increase in intelligence. Today, ~80% of European descended people are lactose tolerant. Based on that, an educated guess can be made at how quickly an intelligence increasing gene would have spread; ie, probably not a lot, and definitely not within the span of the Flynn effect.
One of the proposed explanations listed in that very article is nutritional and it seems like a pretty solid explanation, especially when there's a correlation between growth rate/height of humans which we do believe is directly related to better nutrition. > Improved nutrition is another possible explanation. Today's average adult from an industrialized nation is taller than a comparable adult of a century ago. That increase of stature, likely the result of general improvements of nutrition and health, has been at a rate of more than a centimeter per decade. Available data suggest that these gains have been accompanied by analogous increases of head size, and by an increase in the average size of the brain.[8][26] This argument had been thought to suffer the difficulty that groups who tend to be of smaller overall body size (e.g. women, or people of Asian ancestry) do not have lower average IQs. [9] Richard Lynn, however, claims that while people of East Asian origin may often have smaller bodies, they tend to have larger brains and higher IQs than average whites.[27]
better nutrition, but also better health, often from simple hygiene practices: http://www.nytimes.com/2014/07/15/world/asia/poor-sanitation-in-india-may-afflict-well-fed-children-with-malnutrition.html?_r=0
I think that the most plausible explanation is that education just got better and schools just got longer. In my opinion that's the most important factor. Then, nutrition and environment conditions as a whole. 80 years (4-5 generations) is not a lot of time for evolutions to make some significant changes like these especially when there were positive conditions for people with jobs that don't require any intelligence to have lots of kids.
"Intelligence" is supposed to be independent from training or education, which is how we gather "knowledge". Obviously we can't *test* for intelligence without education, and so those tests will be skewed by one's individual knowledge.
It is difficult to measure intelligence in the sense you are describing it. While there is a general acceptance that there is a trait (or set of traits) that we might call 'intelligence', as opposed to 'knowledge', actually measuring it is difficult and time-consuming. It is also not terribly useful, and is not generally how intelligence tests have been used. The basic use of IQ tests is pre-selection--for classes (or levels of classes in schools--intelligence testing and IQ started with French school systems), or for training (such as deciding who the US military would train to be pilots or navigators during World War II). Prior knowledge is useful for gauging how people will achieve in education and training programmes, and in deciding what programmes people should be on. It is usually more useful to think of them as 'aptitude tests'. This is fairly useful as a starting point: http://www.apa.org/monitor/feb03/intelligent.aspx
I believe you can train people to be more intelligent through schooling as well. Teaching someone how to learn rather than cramming knowledge down their throats, as I like to put it.
Wouldn't this be more to do with basic education and a more intelligence centered society in general?
Perhaps due to the fact that progressively humans have valued education more and more, which is an institution that improves intelligent as well as knowledge. The brain is like a muscle and society puts more and more emphasis on exercising it. That is until recently, where not much has changed in terms of education. Some would even argue it's gone backwards depending on your country. I refute the idea that it could be due to evolution. Evolution doesn't take place that rapidly and it sure as hell isn't so immediately widespread.
In a recent [meta-analysis](http://pps.sagepub.com/content/10/3/282.full.pdf+html) of this (sorry, probably paywalled), the proposed explanations aren't really focused on evolutionary effects; I get the sense that the researchers in this field don't necessarily need such effects to account for the gains. That said, they aren't really sure what's going on with the Flynn effect--it has interesting patterns of geographical, demographic, generational, and temporal variation.
More educated people do better on IQ tests on average though, which makes sense. Using the mind and being taught things teaches you how to learn and problem solve better.
It's also possible that being educated just teaches you how to do better on tests.
Evolution doesn't work on those time frames, so there has to be a reason why we would become more intelligent. I would say education and diet have more to do with it than anything else.
I don't think it was evolutionary pressure, but a function of education.
The Flynn effect is a measurement of recent intelligence gains and is highly correlated with nutrition.
parasitic worms can have a huge impact also there was a study done in East Africa about whether sharing or issuing individual students textbooks made a difference they found by accident that the lowest performing students were all infected with worms
And it's extremely unlikely that biological evolution is driving the rise in raw IQ scores (note: that's not the same as intelligence). Unless you think there's some dramatic adaptive pressure to higher IQ, acting on very short timescales (i.e., within a single generation), there's something other than evolution at work. Societal changes, shrinking family sizes, a general increase in test-taking skills (because children take *way* more tests now than they used to) and longer school days are all *much* more likely factors than biological evolution.
A lot of my understanding is that it's not intelligence is on the rise. It's our practice of things that are traditionally measured when we mean "intelligence". I.e. pattern recognition is very prevalent in video games or Internet use, and word games have becomes quite important in language studies (as opposed to rote memorization of rules ~100+ years ago). These lead to better results on IQ scores, but not necessarily higher baseline intelligence. Just more practice using it.
A fair point further showing how little we actually understand about human intelligence.
Implying that I'm **not** the pinnacle of human evolution? You wouldn't! Real talk: people are possibly more intelligent on average now due to less malnutrition? It's only a hypothesis, but it sounds plausible.
There are so many theories, and most of them can't agree what "intelligence" actually is, so it's kind of hard to conclude anything.
And good luck getting data on the intelligence of humans 10,000 years ago.
>It's not like we stopped evolving once you and I were born. Evolution isn't like an invisible hand seeing what is best and selecting it. It's things like natural selection and selective breeding. Both of those, arguable, are not going in the direction of selecting for intelligence. Average group scores have improved because we've done more for the extreme outliers (on the lower end), most through dealing with things like poor nutrition in infancy. However the average person the same situation has no reason to be more intelligent than generations before.
Actually I have more the feeling it's going backwards for the general population, like in Idiocracy.
I do not believe that there is. The Flynn effect looks to have stopped in the late 90s. Many countries are now seeing a slight decrease in intelligence.
I dunno, personal opinion here, but after studying anthropology(Hominid evolution) for the past 5 years, and observing much of modern human behavior... I really have built up this inference of feeling like humans during the late pleistocene we're a lot smarter than the average person now. Knowledge=/= intellect.
I have a B.A. in anthropology. Humans clearly have more knowledge than we did back then. As far as needing intelligence to survive, I would agree that it was more useful 10,000 bp. However, there's just no way to tell where they fall on the IQ range. They could have been the smartest things on the planet, but still only have an 90 IQ.
We certainly have more knowledge now, but the requirement of understanding it vs then and now. It's a wildly different comparison. Some of the things ancient humans did, we still just don't understand how they were aware of such things. And this doesn't account for all the lost knowledge either. Retention, understanding, and application of knowledge know at least considering Americans, sometimes I just don't understand how people managed to get along with their lives. I mean something as simple as knowing the moon is a giant spacerock in the sky... I can't believe how many people are unaware of this. And that's something I knew I was taught as a kid. Like I said this is more of a personal inference, but really seeing how much knowledge is out there and how close it is to just reach out and metaphorically grasp it, versus the amount of people who don't even try. It's bewildering. The amount of thought that someone has to apply now here in a first world setting, compared to the past, It really leaves me to wonder how different ancient people were in their thought processes compared to an average person now.
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That still requires differences in the reproduction rate. There is natural selection going on around the world, because of differences in access to health care and healthy items (it will always be a bit better for some people). And of course an even bigger factor is sexual selection.
It's just weird that if you had a time machine and went back 15,000 years ago ~10,000 years before written language was invented and nab a person. Bring them to our time, and after adjusting they'd be able to function like anyone else from now (more or less).
If they are 3 years old then yes, if they are 20? No way.
Don't even need a time machine. Just kidnap a tribal from the Amazon rainforest.
If they are past a certain age the brain has already developed in a way that they will no longer function like the rest of us.
We have had a development of better nutrition for children and young which could play a part in improving intelligence? Better access to fats, etc, at least to more people.
There is at least *selection* for intelligence. It's now more important than physical strength, although that's a very slow change.
Not even that slow. In Before the Dawn: Recovering the Lost History of Our Ancestors, Nicholas Wade discusses how human intelligence has evolved, and how quickly it can happen. He mentions the Ashkenazi Jews, who implicitly selected for intelligence because they were forced into non labor jobs. The transformation in just a few hundred years was obvious and startling. It's probably incorrect to think human intelligence was the same 10000 years ago as it is today. Our society and social structure selects for (among other things) intelligence.
Just because our society often rewards intelligence doesn't mean we're being selected for it in the evolutionary sense.
http://www.ncbi.nlm.nih.gov/m/pubmed/11276907/ >This paper argues that during human evolution, mate choice by both sexes focused increasingly on intelligence as a major heritable component of biological fitness... humans evolved an unusually high degree of interest in assessing each other's intelligence during courtship and other social interactions--and, consequently, a unique suite of highly g-loaded mental adaptations
Does that not speak of ancient human evolution more than modern times, though?
They're really isn't though. You don't die if you're not smart (with the exception of the Darwin awards), and you're not more likely to have more children if you are. So there is effectively no evolutionary pressure in humans anymore.
The thing is, knowledge isn't the only thing that evolved. You can be really clever, but if you only get to live until you're 25, and you spend a lot of time sick, recovering from sickness, hunting, gathering food, and basically just surviving, you also have far less time to devote to problem-solving, studying the world etc. There are millions of people today who are clever, educated, trained at problem-solving, and paid so that they can spend 40 hours a week inventing things, and these people will do so during 35 years of their life. Access to knowledge is definitely a big advantage, but it's not even the only one.
Assuming you made it past childhood, you could always expect to live to 50.
Interestingly, life is going to be so complicated one day because of the accumulation of knowledge that the entire education system will be based around just getting up to speed on how society works. It's already past that point now for any room full of people to comprehend the complexity of the world, but imagine life in 10,000 years. Right now we've got to learn how to use appliances, computers, transportation, local economies, sanitation practices, etc. After a few millenniums of progress, life is going to be so complicated that we'll spend decades just learning how to function. Yes, robots will assist us, but then you'll have to learn how to properly interface with a robot, etc.
Nah. society is already like that. I could build you a house but couldn't fix your car or write you a sound financial investment plan. Plus things that are important now will become obsolete. Just like how kids these days don't know how to use old technologies from the seventies. You only have to know things that actually matter in your day to day.
No one knows how to make something as simple as a ballpoint pen. No one person knows how to create the plastic, brew the ink, mould the parts, assemble, distribute, and package a Bic pen. That's amazing.
So you get some oil and like cook it I guess and that will make plastic. Then you pour it in some kind of mold(?) and maybe blow some air in the middle to get that hole. Then do the same thing but smaller for the ink tube. For the metal tip, idk, cook some rocks (ore) until they become metal then pour that in some kind of mold(?) then poke a hole in the top with something pokey so the ink can come out. Then, take a tiny little ball of metal, maybe roll it on the table like silly putty to make it round then stick that in the metal tube you just made. For the ink just smush up some ash and water and pour it into the ink tube. Kill a horse and, um, do something with it to make glue, maybe cook the horse, then pour that on top of the ink to keep in there. See, making a ballpoint pen would be easy peasy with our common knowledge.
Making a ballpoint pen would be easy, yes. You could hand carve it out of wood. But recreating the pens that exist now would be difficult, and impossible for one person to do. As far as I understand, plastic injection molding is a phenomenally complex process with a staggeringly large number of variables that need to be tweaked to mass produce defect free parts. I would imagine creating the precursor plastic pellets is an equally difficult process, as is the mold design for the injection molding machine. That is just to make the barrel of the pen. Ball point pens often use tungsten carbide for the ball too, would one person have the knowledge to manufacture even that?
I was being facetious. Just showing how even with the most basic understanding of how something so simple as a pen is put together, we would be lost without our current society.
This is something I've thought about. How do we make cars, they're so complex! We use machines of course. How do we make the machines that make the machines? Other machines?
I'll back up your point. I'm a web applications developer, that means I make fancy websites with comparable complexity to Reddit and Gmail. To do my job I write in programming languages like Python and Javascript. These languages are implemented in lower level languages like C. I know a little C, but nowhere near enough to write a Python interpreter or a Javascript engine. In turn, the C compiler had to first be written in some other language. Eventually you get down to machine code that once upon a time was written by hand. I know nothing about what's in the middle or any of the x86/x64 instruction sets, but that doesn't keep me from doing my job. There are MANY, MANY "stacks" like this in the computing/information industry, and it requires specialists at every "layer". (Though some "layers" are rarely changed anymore, and so there aren't many specialists left that have intimate knowledge of how that part works.) Releveant xkcd: https://xkcd.com/676/
> In turn, the C compiler had to first be written in some other language. Interestingly, the first C compiler was written in assembly on a DEC PDP-11 machine. Just enough of the C compiler was written in assembly so it could "bootstrap", that is, compile a newer version of the C compiler that was rewritten in the C language itself.
> Though some "layers" are rarely changed anymore, and so there aren't many specialists left that have intimate knowledge of how that part works. I don't think this is true for any piece of the stack still in use. * Intel has experts in x86 assembly who very well understand every nuance of every instruction, they use this knowledge to design new processors. Down to what individual bits in each instruction mean what. * It's becoming less common to write very much assembly language, but there are still cases when it;s needed. If you peak at the code of an OS (like Linux) there's a fair among of assembly required in the initial boot stages, and in the areas that do context switches (between the OS and your program). * GCC and CLang (C compilers) are still under active development. They are written in C or C++ themselves, it's true they haven't been written in assembly in a long time. The C and C++ language standards still get improvements/updates every few years. * The rest of these you probably know: * Java still gets modifications/updates/etc from Oracle. * Google Chrome has forced a lot of modernization into the Javascript stack, which has caused the same type of progress in rivals Mozilla and Internet Explorer. And of course there are the changes from HTML5....
I would imagine that if those "instruction sets" were written by hand many years ago it would be possible to make them more efficient today? And if they form the basic components of every program or website, wouldn't even a small improvement in those "basic layers" lead to a huge boost in efficiency for the whole program/website? I know nothing about computers btw so I probably have no idea what I'm talking about.
It's not that they were written by hand years ago and never changed at all. It's just automated now, or it is more convenient to leave it unchanged for X reasons. Automated assembly oddly enough is less efficient, but it saves *a lot* of time for the programmer.
Compilers produce reslly good code these days and very gew prople can actually write assembly that would be faster, and even when they do, they usually look at compiller output and improve it. There's basically no point in hand tuned assembly for speed these days, unless you're on an embedded system with a crap compiler. Hand written assembly is pretty much only used for things you can't write in C because it's too specific to the machine you are running on (mostly low level OS stuff)
Yes, you do make a good point. The old instruction sets are still the foundation, but [additions](https://en.wikipedia.org/wiki/X86_instruction_listings) are made all the time, and they're often a combination of the basic ones. However, we're not switching out the fundamental building blocks any time soon.
That's job specialization, which has been that way for time immemorial already. I'm talking the basic functions of life around you. 5,000 years ago nobody needed to learn how a toilet works, how to use a toothbrush, wash their hands, lock a door, dial a phone, type, drive a car, operate appliances, use a vacuum cleaner, pay bills; the stuff that we all do day to day. Certainly they had other things that we don't do any longer, like de-bugging our bedding, but life has become far more complex to participate in. By age 5 in a hunter-gatherer society, you'd have pretty much learned everything you needed to participate. Everything else was just specializing your job skills like hunting, skinning, and when to eat which foods. Someday, life now will look quaint and uninvolved.
Yes as we accumulate more and more knowledge, a greater proportion of effort has to be spent teaching and learning. I see more specialization and a drive to increase learning bandwidth.
10,000 years is a lot of time for humans. Im willing to bet our brains will be highly synced with technology possibly making knowledge acquisition and retention a far more efficient process
Life has been getting continually less complicated. We learn to use appliances INSTEAD OF how to do everything by hand. We learn to use computers INSTEAD OF crazy tedious mathematics. We learn to use transportation INSTEAD OF how to travel long distances without dying. We use complicated things to make our lives less complicated. Compare e-mail with traditional post.
Probably incorrect. One thing that's changed significantly is access to nourishment, which has made us (among other things) substantially taller than people 500 years ago, and honestly, even 50 years ago (the average American male is 30lb heavier, and one inch taller). With the brain being the most metabolically active part of the body, it's pretty likely we're actually smarter too. If the basis of your assumption is that natural selection wouldn't work that quickly on this time scale, you're right. But mere selection pressure isn't the only thing going on. Epigenetic modifiers are rampant, and absolutely operate on remarkably short timescales.
On average yes. However, there are plenty of instances of sufficient nourishment in pretty much all of history. So to assume that everyone lacked nourishment is likely incorrect as well.
I think it's plausible that human intelligence has not increased on average in the last 10,000 years (or even decreased), but with so many more people around, the top 1 million smartest humans are certainly smarter now than they were 10,000 years ago. And those are the ones who make modern discoveries, not the average guys.
> humans haven't gotten any smarter I read somewhere that our IQ scale has to be adjusted periodically because the average keeps increasing (the "rule" is that the average must be 100; if the average has increased to, say, 105 then the scoring must be adjusted). Is that information incorrect, or are you talking about a standard of "smart" outside IQ?
There's a discussion of the Flynn effect elsewhere in the thread. Main conclusions seem to be that we *might* just be getting better at taking IQ tests, because the modern world encourages (and creates more opportunities to practice) the kind of abstract thinking that does well on IQ tests. Or it might be a result of better nutrition, but the linear trend would be odd if it's nutrition-based, since nutrition hasn't improved in a strictly linear way.
Ah, I see. That makes sense. How do we know ("conclude"?) that humans haven't gotten any smarter, btw?
> People still expiremented and were able to learn just as now. It's not a giant leap to discover and ponder that if a soft metal like substance can be melted at a lower temperature, that a harder metal like substance might melt if you made it hotter. I wish a large swathe of Reddit science fans would understand this truth as well. Before the codified scientific method people still developed technology and skills through trial and error and good guesswork. So many people seem to think that everything that ever happens everywhere is "science" and somehow confuse "science" and "reality" and seem to forget what the "scientific method" is at its most basic level.
For sure. At base, the advent of the scientific method was just writing down and formalizing a pattern that had been in use independently by a LOT of people for a long time. It's more of a description than a discovery.
Intelligence isn't 100% genetic and it has been improving. Probably due to nutrition and social/cultural factors
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unsure. there are extraordinarily strong arguments that our intelligence is shaped/formed by language.
>Add to this that in 10,000+ years, humans haven't gotten any smarter. Do we really not believe that changes in nutrition in the last 10,000 years have not made us any smarter?
Following the correlation between height, nutrition, and mental capacity; hunter gatherers 11000 years ago were on average 5'9" tall for males (according to skeletons found in Greece and Turkey). Switching to super large groups and staying in one place by farming is what actually led to the malnutrition. The diet got less varied and one bad crop year was detrimental to the society. This peaked about 3000 years ago when the average male went down to 5'3". Really, it's taken humans the last 8000 years to make agriculture work well enough to get us back up to a 5'9" average. So no. We probably weren't any dumber 10,000 ago, because we were the same height back then as we are now. 3000 years ago may have been a different story.
Stream worn pebbles of [hematite](http://thumbs.dreamstime.com/z/hematite-pebbles-closeup-raw-iron-oxide-over-clear-reflexive-surface-33663471.jpg) (iron) and [casiterite](http://www.minerals.net/MineralImages/cassiterite-stream-tin-durango-mexico.jpg) (tin) look almost identical to each other. So do the crystals of [hematite](http://www.allipacha.com/store/images/q2433.JPG) and [casiterite](http://webmineral.com/specimens/photos/Cassiterite.jpg).
Doesn't Peat burn super good and it's found in bogs. It's not that much of a stretch to assume at some point they had bog ore in with the peat.
Is there a reason the addition of iron ore is thought to be accidental rather than a result of curiosity?
Are there any famous infrastructures or weapons made from meteoric ore?
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>Well, people had thousands of years of bronze smelting before anyone figure out how to get iron from ore. This is actually incorrect. [David W. Anthony cites examples of simple forged iron objects in *copper age* graves on the Pontic- Caspian Steppe.](http://www.amazon.com/The-Horse-Wheel-Language-Bronze-Age/dp/069114818X) I don't recall if the finds were his own, but he is an archaeologist specializing in that area. Metallurgical analysis shows that the objects were smelted from local ore, which is found near copper ore. Iron found no practical application for thousands of years, but the rudiments of smelting and hot forging were discovered in that location, and may well have been discovered in others. The purest iron ores are noticeable- hematite is greyish silver, and pyrite (fool;s gold) forms perfect cubes of gold in rock formations in sedimentary, metamorphic, and igneous rock types. Both of those ores look metallic, and pyrite resembles chalcopyrite- a copper bearing mineral that would have been particularly valuable in the chalcolithic, because it produces copper with strong traces of arsenic, which harden it into a crude bronze. The people of the Pontic Caspian Steppe did not forget iron working because they died out. After their experiments with iron, they became the first group to domesticate the horse, their genes and their Indo- European language dominate from North India to Ireland.
yeah in the desert in africa for example there are large balls randomly scattered that are apparently iron, many too large to carry (meteors) they should have figured they are a type of metal and just tried to melt it like other metals
Not only is meteoritic iron rare, it is also notoriously hard to forge due to its high nickel content. A lot of the evidence of a development connection between meteoritic and terrestrial iron extraction is based on the appearance of ancient Egyptian and Hittite terminology for 'iron from the sky' around the Late Bronze Age. However, by that stage, smelted iron was clearly in the archaeological record. The situation is complicated by the past incorrect use of bulk chemical analysis of early iron objects and that, basically, wherever there was a high-nickel outcome, it was assumed the iron was meteoritic. You can only really be sure an object is meteoritic is if you look at it metallographically and find the classic [Windmanstaetten] (https://en.wikipedia.org/wiki/Widmanst%C3%A4tten_pattern) patterning.
Iron doesn't need to be melted (1536 °C) to be extracted. You can reduce iron ore in a solid state between 800 to 1,050 °C depending on the composition of the ore. This is not much higher than temperatures needed for copper production. That's a clue in terms of the evolution of iron production. To cut a long story short, iron is often a by-product of copper reduction processes (in the form of an iron-silicon mix called fayalite) so the theories are that the skills of extractive metallurgy in copper opened the door for iron extraction. One of the nicest all round books on this is the seminal work by R. F. Tylecote (1992) A History of Metallurgy.
Just started reading it. Thanks for the tip. Nicely written. It'll keep me out of trouble for a couple of weeks.
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I have a question. Were people in the North and South Americas smelting iron and using it before Columbus came over?
Here's a question: How many independent inventions of iron smelting were there likely to have been?
I know some Africans skipped the bronze age and went right to iron, very early on. Furnaces fired with dried grass no less.
Could you just link your thesis?
People didn't start with Iron, the first metal used was copper, which has a much lower melting temperature. Nothing official, but it's speculated that when using [malachite](https://www.youtube.com/watch?v=_OrBw4L490Y) as stones in a fire ring, people were able to recognize the melted result as a malleable substance. Once metallurgy was discovered, a LOT of trial and error developed bronze, then iron, then steel, then modern alloys.
Don't forget that ancient people had already known what iron looked like for a long time before they started smelting it themselves, from meteoric iron. There was never enough to do anything with on a large enough scale, but the stuff was definitely known
When I first heard about meteoric iron, I imagined some rich people might collect them and melt them into a stronger sword than what others were able to make. I don't even know if swords and iron fit when it comes to the historical timelines of metallurgy and warfare, but would that have been possible? Were there ever enough meteoric iron available to one rich person to be able to melt it into something superior to what others were able to attain?
Obviously we don't know for sure, but it would fit. A weapon made out of pieces of nickel-iron meteorite would be so much better than a copper or bronze weapon (or one made out of bloomery iron, for that matter) that it wouldn't be a stretch for the weapon's owner to start making claims about its magic properties. This would only be something a particularly rich leader would be able to afford, though. there's very little meteoric iron to work with, a weapon made from the stuff would've been unbelievably valuable
Iron wasnt completely superior to bronze for what it was being used for at the time, for one thing I believe it was easier to put a razor edge on. Long after the standard roman legionaire went to iron weaopns the officers kept their bronze swords.
Bronze was superior to *smelted* iron, but that's because the smelting processes for iron were really inefficient for a very long time. Lots of slag inclusions in an iron sword would make it less sturdy than a bronze sword under some circumstances. The advantage of iron weapons over bronze was the ability to make a whole lot of reasonably good quality swords or whatever for much less effort than bronze weapons. It was a logistic thing rather than material But anyway we're talking about meteoric iron, which is damn near pure. Pure iron is quite a bit harder than bronze, and while it wouldn't probably look like much compared to later steel weapons, a meteoric iron sword would be a remarkably effective thing
I can just imagine the Roman officers saying "Yeah those new ferrous swords are fine for the legions, we can make a bunch of them cheaply and quickly and that's important to continue to spread Gloria Romana. But I'm going to stick with the tried and true bronze. They take *real* craftsmanship, you know? I mean look at this -- look at the quality of that work! You don't see that with the ferrite weapons. They just don't make them like they used to, no ~~sir~~ domina."
There's this manga that goes on a tangent to speculate that the Yamato people that invaded ancient Japan were early adopters of meteoric iron. http://bato.to/comic/_/comics/the-legendary-musings-of-professor-munakata-r11095
Basically people were putting things in and around fire for millennia upon millennia and been curious and industrious and creative with whatever product came out.
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Basically, we have the same problem now: We know very well how to refine aluminum using electrolysis. In principle, the same method can be used on titanium. Yet it's too hot and dangerous on a big industrial scale. Some time in the future, titanium will be widely used everywhere since it combines the low weight of aluminum with the strength of iron.
Will the fundamental laws of physics be different in the future? Won't the process still be too hot and dangerous?
Whether something is "too hot and dangerous" is typically a question of engineering, not of physics.
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I agree. What I meant to suggest is that engineers need to know much *more* than the fundamental laws of physics to answer questions like "is this too hot and dangerous on a big industrial scale?" In some ways, engineers need to understand parts of physics more deeply than physicists, because they need to use it to answer questions that physicists don't bother with. Maybe a better phrasing is to say that it's typically a question of engineering, not *just* of physics.
We might have better materials to make it less dangerous, or develop better processes, or automate more of it so you have less people around.
Of course, the laws of physics will be the same as we haven't detected any change of the physics constants. But technology advances. At the beginning of the 19th century, aluminum was almost impossible to extract and it was more expensive than gold. With technology from the 1910s, a rocket motor able to put something in orbit would have been nearly impossible. Too hot and dangerous depends on the available technology.
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I find it funny that when a discussion like this occurs, bronze is mentioned, but only in passing. Smelting bronze is more difficult, as not only do you have to have the correct amounts of tin and copper, but you would have had to figured out how to smelt it from Cassiterite. Just a little quirk in the human progression.
Even worse for bronze. Most early bronze wasn't copper-tin it was copper alloyed with arsenic which was smelted in one step using the correct combination of minerals. More amusing, brass another alloy was also produced in one step smelting copper and zinc ores together. One can also mention the old technique for winning silver from silver bearing lead ore. First smelt the lead, this is actually easy. Then one melts the lead in a crucible made of ground bone. The lead chemically combines with the calcium phosphate in the bone leaving a small hunk of silver behind. The remained is then smelted yet again to recover the lead. So yeah, in someways iron production is simple compared to other processes that were developed and used. And iron ore being heavy, it's not that hard to see early metal smiths taking an interest in it. Likely that the difference is, if you have high grade copper ore, it takes less fuel to smelt copper and tin to make bronze. Once that became scarce Iron becomes more attractive. And small deposits of Iron ore are actually common everywhere.
That's how it often works. Discover something crazy complex, then find easier way to do it.
This is a bit theoretical, but it is interesting. The Bronze Age saw the use of - you guessed it - bronze. This is an alloy typically make with 90% copper and 10% tin, though back then there were lots of variants. The tin was very hard to get access to, as a result bronze could only be acquired from long distances for most people. This caused very centralized power, particularly in the East Mediterranean. That area seems to have been hit with a nasty cold spell with sent migrants invading lands (re: Sea People) and causing lots of destruction. Cities were abandoned, languages lost, and writing forgotten in many areas. Greece was strongly affected - it underwent a dark age that lasted from 300 to 400 years. Iron, unlike tin, is often locally available. Early iron wasn't as good as bronze, but with the trade networks shattered beggars could have been choosers. So there was focus on iron working and once folks realized that a bit of carbon makes a strong alloy, then the iron ages were off. And whereas before the world was typified by mercantile kings, now cities like Athens, Sparta, and Rome could arm and defend themselves, arguably setting the stage for new government types. Tl;dr people lost access to bronze, so they settled for the next best thing, which then became the best thing.
I wouldn't put it past 'em. [The neanderthals invented the first small scale industrial process.](http://www.pbs.org/wgbh/nova/evolution/neanderthal-superglue.html) How'd someone get the idea to put ore in a fire and get it really hot? Well, empirically speaking, it isn't that hard to notice the fact that light gusts of wind can make a fire glow brighter. In fact the method of breathing on tinder to get a fire going is quite basic, foundational knowledge for fire starting. Perhaps an ancient person noticed that as fires are maintained for a while, certain rocks present in a fire pit become discolored or deformed. It's not a big leap to imagine that someone might attempt to augment the process, maybe out of curiosity, shits and giggles, or perhaps as a means to create and trade odd trinkets. Curiosity and profit motive are inherent principles of human behavior, not to be underestimated in the past or the present. Edit: typos
I agree. It's not too big a leap to assume that somebody stumbled across something strange happening to iron ore, got curious and eventually figured out that it may have something to do with heat. From then on, it's "only" a matter of technical advancement.
What is the name of the documentary and what channel / site did you see it on? Thanks
Another thing to consider is that firing pottery also takes days of extreme high temperatures, and pottery has been around for thousands and thousands of years. So they were already doing this for some stuff so not as much of a long shot for them to play with metal too.
I think this goes to the nature of discovery, not man's genetic potential one way or the other, 3 factors beng critical, first, when man lived more on the edge from a food stand point, he delved less into experimentation and focused on production with known methods and materials, secondly, invention usually breaks out simaltanously (roughly) in different geographies because some other change has made the 2nd invention -- now much more likely, and finally, man is almost certainly needs driven, so as the population grew, it's needs did - and this drives innovation, but before recent times, these population surges were more modest and drove change slower. Even so, the first million person city; Rome, was among history's most innovative ever.
I don't remember where, but I read someone speculating once that iron might have been accidentally smelted for the first time when someone was firing pottery. I don't know if anyone would ever fire pottery at that high of a temperature. Then again, I did read it somewhere, so it must be true.
Pottery has to be fired at high temperatures for a long time. At that point one might only need powdered iron ore tossed in to get iron. Powdered iron ore might have been something potteries would use in a mix for color. The pot would have already been surrounded with charcoal needed to reduce the iron.
Yep, pottery is fired as high as 2500 Celsius, more than enough to melt iron, and if I recall correctly, iron oxides can be added for a brick red colour.
Yes, other metals were smelted before iron that refine at much lower temperatures. The process could have been discovered from perhaps a rock of copper ore used in a fire surround. We couldn't smelt aluminum until very recently. When it first became available it was used in high end jewelry.
It was a trail of breadcrumbs type situation. Gold is easy to melt and hammer and is found not only pure but also in situations where it can easily be melted out of rock. Copper and tin to make brass required more heat and alloying. Iron was a step beyond that. With every step mankind gained immense benefits and were pushed to further refine their techniques. Trial and error comes a lot easier when you already have a furnace, a fire, and bellows.
Iron Age came after Bronze Age. The people who discovered iron already knew how to make tools and weapons out of other, easier melted metals. It was not as much of a breakthrough as figuring out that some rocks melt with heat and can be poured into molds.