Are humans getting cleverer?
bbc.co.uk
bbc.co.uk
The problem is, that's about the only part that has risen. The limited number of subtests showing the gains has long been one of the big question marks about how the Flynn effect could possibly be about the underlying intelligence rather than an artifact (https://en.wikipedia.org/wiki/Flynn_effect).
> This is a puzzle not just for the US, but for all countries demonstrating the Flynn Effect. "Does it make sense," Flynn wrote in one paper, "to assume that at one time almost 40% of Dutch men lacked the capacity to understand soccer, their most favoured national sport?"
This sort of point comes up often, but it's not a good point to make. The people discussing IQ tests typically have lived in a tight bubble their entire lives and have not meaningfully interacted with the general population. They typically have even less interaction with the populations of poor countries who might be comparable to long ago. For example, just today I was reading a Wired article which remarks offhand that "In some areas of the country, up to 40 percent of children under 5 are affected. The effects are mental as well as physical. A 2008 study by the National Intelligence Council found that a quarter of North Korean military conscripts are disqualified for cognitive disabilities". Flynn asks whether it's possible for a quarter of Dutch men at some point to not be able to follow soccer well; I ask whether it's possible for a quarter of North Korean men to be rejected by the notoriously voracious NK military because they are too stupid or mentally broken. The latter seems to be true, however...
1. Better nutrition and medical care. 2. Teaching abstract concepts such as predicate logic early on. 3. Increasing complexity of the world in terms of information streams. 4. Urbanization of population. 4. Mandatory schooling and various programs aimed at increasing graduation rate, which is proxy for total amount of time an average child is schooled [0].
I was writing out long and detailed argument based on clustering of scholars and their presence in ancient civilizations, but after realizing amount of details such argument would need to stand I gave up. My argument was along the lines of: presence of clusters of extraordinary scholars in ancient civilizations show that prospering economy[1], knowledge communication, and education play crucial role in preparing those scholars.
[0] Now thinking about it - I think there should be strong correlation between average time children are schooled and standardized test scores. Probably also has additional wide variety of rippling effects including better economic growth.
[1] An economy that is capable of bearing load of academia.
Surely the simpler explanation is that the tests don't really measure "pure" intelligence, and the results are affected by all sorts of social features, including a general familiarity with IQ tests. Time-in-school is part of that.
Jared Diamond makes a similar argument in Guns, Germs, and Steel for why the people of New Guinea are smarter than their western counterparts.
The important thing to note is the human population covers the globe. There are plenty of sifts in populations like Lactose tolerance becoming widespread over the last 7,500 years, but even that is a long way from becoming effectively universal.
That's generally a vary slow change consider most animals don't need dietary vitamin C even if there diets provide plenty of the stuff.
However, you used the term "a few generations" as in below 1,000 years and that's rediculusly fast for a species that takes as long as we do to reproduce and have so few children.
That said, you mentioned a beneficial trait becoming neutral, and that's making the assumption that greater intelligence is neutral. It could be that larger social organizations reward slightly less intelligent critters. That would do the trick rather quickly. I'm not making that claim, but am saying that discussions around evolution and traits that we have bias toward seeing as "good" are fraught.
There's also the further issue of intelligence being a very nebulous term that encompasses tons of cognitive traits, which makes any discussion of intelligence in evolutionary terms even more difficult.
It's also possible that some of what we call intelligence is epigenetic.
Just 500 years ago lots of people in North America where living nomadic hunter gather lifestyles. Even just 100 years ago you could find tribes in many parts of the world still living hunter gather lifestyles little changed over the last 15,000+ years and probably similar to how people lived 100,000+ thousand years ago.
As to epigenetic factors, the classic hunter gather lifestyle could be very healthy as long as population numbers stayed low. Farming actually lowered many heath indicators even as it allowed for massive increases in population sizes.
PS: Anyway, evolution is only 'fast' when there are significant benefits or harms. If a single mutation or environment change increases survival chances by say +/- 1% it takes exponentially longer to spread than a +/- 10% change.
"Farming actually lowered many heath indicators ..."
Indeed, it's uncontroversial that farming degrades the heath.
I do want to mention that larger social organizations were quite widespread in the Americas, despite the existence of hunter-gatherer tribes. The new world certainly wasn't an uncivilized wasteland when Europeans arrived.
Epigenetic factors can be triggered buy group size (domestication) as well. So those hunter-gatherer tribes might share the same genetic traits but express them differently based on their environment.
I don’t recall the study, it was either men in the US or Britton. But, income was positively correlated with number of children. Income and intelligence are also linked so that's evidence that right now intelligence is positively correlated with number of children. This may be strongly linked with prison time but again that links with intelligence.
The important thing to note is men often have children with more than one person and can have children vary late in life.
http://en.wikipedia.org/wiki/Human_height#History_of_human_h...
There is a fundamental mistake in assuming a "couple generation" linear trend will continue to infinity providing us with 30 foot tall men with IQs of 200+. We are probably at or around peak height and peak IQ right now for various rather obvious income inequality reasons, and we can expect both to decline in the future.
There is a coupling between womens pelvis size and newborn head size and medically assisted survival during childbirth which could provide some multigenerational effect to growth.
There have been a lot of arguments relying on generational inheritance of intelligence / IQ, however:
"As Flynn pointed out in his Ted Talk on the Flynn Effect, in 1900 only 3% of Americans performed "cognitively demanding" jobs - now the figure is 35%"
That would imply the percentage of humanity where cognition has no effect on their job, and presumably lifestyle, is at least 65% and has always historically been higher, as high as 97%, so an evolutionary argument for IQ growth seems extremely weak. It would be as if doctrine were peacock females select their mates based on tail feather size leading to large tail feathers, yet actual data shows 97% to 65% of actual living peacocks come from bald ancestors.
Other humans!
You have to outsmart them and avoid being outsmarted by them, because they compete for the same resources and some of them will act in a predatory manner.
1. http://en.wikipedia.org/wiki/Fertility_and_intelligence 2. Kaufman, Scott Barry, et al. "The role of creativity and humor in human mate selection." Mating intelligence: Sex, relationships, and the mind’s reproductive system (2008): 227-262.
What about the multi-generational odds of survival and reproduction? What about surviving famines or predators? What about competition in sexual selection?
Idiocracy was an amusing movie, but it's underlying premise was never realistic.
You know, like when you're Amazon and you build a huge infrastructure to serve existing business, only to realize later you could do a lot more with it by simply re-purposing and re-configuring.
http://en.wikipedia.org/wiki/Heterosis
http://en.wikipedia.org/wiki/Heterozygote_advantage
I also must point out that "hard selection" (differential survival) is not the only operating mechanism in evolution. In complex organisms that reproduce sexually, it might not even be the dominant mechanism. You've got sexual selection and genetic drift, which in a species with low infant mortality and low mortality in general (a.k.a. us) are probably the dominant mechanisms. Beyond those you have things like the Baldwin effect, which get very interesting when coupled with epigenetics. Epigenetics is unquestionably real but as yet is not well understood. There could be all kinds of interesting things going on here.
It's almost like how a goldfish will grow to the size of its bowl-- new humans will grow to and exceed the standards of the last generation, it's just human nature.
It's a bit trickier to apply the principle to creative pursuits than it is to physical ones, but I think it may help explain why students could appear cleverer over time without anything changing biologically.
To give one final example that doesn't involve sports. I am a trumpet player and am pretty familiar with the phenomenon that the best of the best in trumpet playing goes up as the decades go by. Rafael Mendez, Maynard Ferguson, etc. will forever be considered as the all time great virtuosoes, but the cold hard fact is that their technical abilities were only good in light of the time-- exceeded by hundreds if not thousands of the best trumpet players today. It's all about context.
We evolved to be the master hunters and nowadays our children aren't even aware meat comes from animals.
This same limited amount of intelligence we evolved with, is then free to do something else, like literature, art and music.
"The second factor is what Alexander Luria discovered when he tested rural Russian peasants in the 1930s. He discovered that pre-scientific people can't take the hypothetical seriously. That is, if you pose to them questions like, "There is snow at the North Pole; where there is snow, bears are white; what color are bears at the North Pole?" they would say, "Well, I've only seen brown bears. And only if a person came from the North Pole with testimony would I believe that the bears there are white."
It seems like the brain doesn't think abstractly when it doesn't need to, and for many thousands of years it didn't. The nice thing about culture and education is that it seems like more than just knowledge is passed down. Whole modes and ways of thinking, perspectives on the world that are useful and revealing now exist in the greater collective consciousness. We can't really measure this, but I think it makes a huge difference that there is this idea that everything in the world is not simply magical or arbitrary and that given the right tools we can figure it out. The idea that there ARE knowable underlying principles that govern the universe (even randomness!) completely changes the way that we think about the world.
Thank you.
Perhaps it's the same with intelligence, where more of us are forced to develop to our potential now but we haven't necessarily raised the bar for our species. I think if you look at other statistics such as college attendance rates they would support this scenario.
Given some truly clueless people I've interacted with in my lifetime, it seems to me that there are plenty of people who may have more generalized knowledge or even be able to reason about some things better but still can't think of a way out of a paper bag let alone a box.
Just because you can use an iPhone, or a remote control for a TV with some understanding of how it works isn't the same as being able to build one. The average man in the 60's in the U.S. had a better understanding of relatively simple things like changing a light switch, or replacing a toilet than the average man today. Understanding more of the machines we use every day is being lost in recent generations imho.
TFA mentions reasoning over memorizing names and numbers, but doesn't mention much in support of that.. I'd say general health of the overall population beyond historic poverty and starvation has had more effect than actual increases in human reasoning.
More than ever is it attractive to be intelligent. We celebrate Intelligence like never before. Intelligence is more likely to lead to work/money/power, and people are more likely to seek mates that are intelligent.
Any trait that is preferable at the time, is more likely to lead to offsprings. Ask your local sperm bank.
I'm not saying I think it's the only, or necessarily the most important trait (Hitler was likely quite intelligent), but it is increasingly important, and therefore increasingly likely to affect the human evolution.
Human evolution is constantly changing us, and I'd say it makes little to no sense, to argue that our intelligence specifically, is not changing with it (for better or worse). But with our short lifespan, it might not change fast enough for some to recognize it.
I think I prefer more clever.
'More intelligent' would probably have been a better choice.