In fact some of our genetic inheritance comes only from one parent. For the two sexes respectively the X chromosomes and mitochondria. But it was mostly a joke. But mostly because this appears to be a recent development and the difference too slight to effect a large evolutionary pressure and rapid changes. However if intelligence is an evolutionary disadvantage for one sex over an extended period, then this is something that will, over time, result in changes to the genome and the intelligence of the two sexes. The reverse would be to say that since we inherit equally from both parents then there could be no sex-difference in either body or brain. Neither of which fortunately is correct.
Actually it’s my understanding that quite a lot of our active genetic inheritance comes from only one parent or the other. It turns out that many genes are “locked down” during the creation of the sperm or egg; which gets locked down being determined by the gender of the parent. For example, women normally have better social skills than men; but a women born with only one X chromosome will on average have social skills no better than a man if the X she inherits comes from her mother, while if she inherits it from her father she’ll on average have the normal female level of ability. So not only are female social skills inherited according to the gender of the parent, it’s from the father not the mother which is interesting.
The thing that everyone should bear in mind when extrapolating human evolution is that evolution is torturously slow compared to the rate of social and technological progress of our society.
So even if the trend is there, it’s just not worth worrying or thinking about; there’ll be virtually no change to average intelligence in the next couple of centuries, but we may well acquire the tech to manually increase our cognitive abilities in that time (e.g. GE, nanotech, implants etc).
Then there’s the whole thing of whether “slow” people having more children necessarily means the population becoming more slow.
To this I think there are a lot of factors that make things more difficult to predict.
e.g. Homo sapiens has quite poor genetic variety. So things like the gradual mixing of African genes into other populations may help to boost intelligence simply as a “hybrid vigour” type of effect.
I’m not saying this is happening; I’m just saying the extrapolation may not be as simple as many assume.
I haven’t had time to read the entire thread yet, so I apologize if this has already been debunked. As it happens, the premise of your argument is false. The fact that the rich have the fewest children is one of those things that everybody knows, just like everybody knows that Hispanic immigrants commit crimes at a higher rate than American citizens. But, in fact, many things that everybody knows are false. Hispanic immigrants commit crimes at a lower rate than American citizens, and the rich actually have a lot more children than any other economic class.
Please do take the time to read the thread. The initial premise has changed and become more robust now. Also, pardon me for not thinking that you have ‘debunked’ the premise of my initial argument when, even if this somewhat suspect source is correct*, 1.5% of americans** have .2 more kids than the replacement rate, when the entire middle class, which can vary from 40% to 75% of the population depending on how you define it(the article does not) is at .3 below the replacement rate. And how on earth did Hispanics and crime rates come into it? Rhetorical flourishes do not serve to make your point any stronger I’m afraid. The opposite is true if anything.
*(it does not explain where the numbers come from, it just plonks them down in one line of an other wise 3 page long, completely unrelated article)
** ( this is the percentage of households earning above 250k a year, individuals will be even fewer - sourced from US census data)
It does happen in the real world to significant extent though, as the data I’ve shown you above indicates. So you’re really quibling over the rate in which selection is happening.
The big problem is international affairs. If you look at the total fertility rate, it is highest in the basket case countries. Niger, Afghanistan, Sudan, Congo, Liberia, etc. People have 5-7 kids per woman.
At the same time countries that are fairly advanced like Japan, Taiwan, South Korea, Italy, Greece, Germany, etc. have a rate of about 1.3. The EU has a TFR of 1.5, so every 20 women on average have 15 kids, which isn’t sustainable long term.
Of course things can and do change. Maybe Northern Africa and the middle east will become wealthy, educated democracies in the next 100 years and the developed world will maintain its population. But the current trend line shows a shrinking in the parts of the world that, at least in contemporary times, play a big role in solving the worlds problems (a lot of medical, energy, scientific, politicial, communications, etc advances come from wealthy countries) and a growth in the parts of the world that can’t even solve their own problems. Japan is investing heavily in robotics and their population may be cut in half over the next 100 years. Somalia is an anarchistic mad max hellhole where over half the population can’t read and women there average 6-7 kids each. The cure for Alzheimers is much more likely to come from Japan than Somalia.
But who knows. I’m sure things will change.
@ Wesley Clark,
Good point, that is likely to have disastrous long term results.
High TFRs in the countries you mention is mitigated to some extent by higher mortality rates in the countries with high fertility rates as well. Even though overall population growth rates are higher, most of these countries are starting out with small bases. Even if they were to get large populations though, it would mostly only be a problem for the populations themselves wouldn’t it? And…
… things don’t really need all that long to change. Take S.Korea for example. It went from a growth rate of 2.8% in 1965 to below 1% in 1985, and has kept dropping. Also ‘democracy’ isn’t a necessary or sufficient condition. Wealthy might be.
Most advances of any sort boil down only to scientific and technological advances. And negative population growth rates don’t necessarily imply a slowdown in science/tech research IMO. For that you’d have to show reduction in funding, research, the number of PhDs etc. Besides, if some places like Japan are on the decline, much larger potential science powerhouses like China (and maybe India, though this is further away in the future) are rising.
bldysaaba, what’s your point in even starting this thread? The fact is that the average I.Q. has been slowly rising in every country where I.Q. tests have been administered for most of the past century, on average by about 3 I.Q. points per decade. This is for environmental reasons, not genetic ones. The things that have fueled this increase are basically effects of the rise in the standard of living. In other words, if all children are brought up in circumstances where everyone will get enough nutricious meals, enough medical care, and a overall background where no one is mistreated and everyone gets an intellectually stimulating upbringing, they will all grow up to reach their intellectual potential and thus the average I.Q. will rise to the highest level possible consistent with their genetic potentials.
What you’re talking about is a possible (not certain, just possible) genetic effect which has been utterly swamped by the environmental effect of rising standards of living causing rising average I.Q.'s. Yes, it’s theoretically possible that if every country in the world has its median standard of living brought up to a level that’s approximately equivalent to that of most upper-class households in the present-day U.S. and if the distribution of income was very equitable in every country in the world, this genetic effect might no longer be swamped by the environmental effect. So what? This is like claiming that you’ve found a theoretical way that global cooling should be happening. You would then claim that obviously the effects of putting more carbon dioxide into the atmosphere that is causing global warming is completely swamping your theoretical effect. You don’t want to worry about global warming though. You prefer that we think about this theoretical global cooling effect which could only become noticeable if the entire world greatly reduces the amount of carbon dioxide produced and otherwise became environmentally stable.
In every country in the world the average I.Q. has been rising except for maybe (maybe!) a couple ones in the past decade which have a very high standard of living and have a very equitable distribution of income. Compared to this, your theoretical mechanism by which the average I.Q. might be lowered by genetic effects is tiny. Even if it proves to be true, what do you want us to do about it? What’s your agenda? Do you want us to ship all stupid people off to concentration camps and have them executed? Do you want us to have them all sterilized?
If you want to do something about the relative level of children produced by people of various incomes, here’s several possibilities: For upper-middle-class people, reduce the amount of overtime they work and make child care available. They really do want to have more children. They are just too exhausted to have them because of the overtime they work. For middle-class people, raise the minimum wage (and, again, make child care available). Increase the number of good jobs. They really want to have more children. They are just too exhausted by having to work two jobs to support their families. For poor people, to decrease the number of children, see that there are good jobs for them. If someone is unemployed, they might be having children just because they see no hope in the future as a contributor to society except by having children.
The fundamental problem with the OP is the implied suggestion that lower class = stupid.
For example, here in Texas, it’s not at all uncommon for recently immigrated Hispanic families to have lots of kids like they would in rural Mexico. However, the number of kids goes down each generation- a friend of mine is one of a family of six, and his parents had something like 5-6 siblings each. He and his siblings however, are having 1-2 kids, or even no kids.
Looking at his family in the first couple generations (who I’m pretty sure were fairly poor), if you made the assumption that poor=stupid, you could easily jump to the conclusion that the stupid were outbreeding the smart.
That isn’t the case; his family is not stupid at all- quite the contrary, as a matter of fact. In some sense, they directly added to the pool of smart people out there instead of the reverse, but it was masked by their lower socio-economic status at the time.
Even in Mexico the fertility rate has declined drastically as the population has become more urbanized.
It might imply that to you, but it doesn’t to the rest of us. It implies: lower class = congenitally stupid, on average, ceteris paribus.
- it’s not clear to what extent the secular rise in IQ scores represents a real rise in general intelligence. For one, the rise is generally negatively correlated with general intelligence (-.3) (though in some cases the correlation is positive), and, for another, strict measurement invariance does not always hold between generations. Both these indicate that at least some of the IQ score increase is “hollow.” It’s, at least partially, the kind of increase that you would get if you handed out test answers before a test or taught to a test.
- and a partial genetic explanation has not been ruled out.
Look, from this and previous posts it’s quite evident that you’re not paying much attention to what’s posted in the thread or in response to you directly, but keep repeating the same point and are now ascribing motivations to me that run counter to what I’ve explicitly stated and implied. If this gives you a warm fuzzy, you’re welcome to it. Now go prove Godwin right somewhere else.
I think the policy implications are that governments should aim to make it affordable and practical for smart women to have children.
In terms of the long term unemployed, welfare entitlements should be conditional on using contraception.