# Select only smart people for a colony. Do their descendants remain smart? **URL:** \ **Category:** Great Debates\ **Created:** [August 13, 2012, 3:20am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341 "2012-08-13T03:20:21Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [August 13, 2012, 4:56pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/41 "2012-08-13T16:56:41Z")
> [@Der\_Trihs](#): > > Or they’d just die out; 500 people is a dangerously small population to start with. They’d also suffer from low genetic diversity; that’s an effect of such population bottlenecks. I’m just curious how accurate that is. There’s likely dozens of cases that contradict that - how many polynesian islands were settled by very small numbers of initial immigrants? Or other isolated locations? Newfoundland, Tierra del Fuego, the Andamans, Madgascar etc. - I suspect that the settlement of Easter Island was from a single canoeload or two of explorers, although there is no record of the details; but there is certainly no record that there was any back and forth after the original settlement. you would think that especially with Easter Island, the initial pool that the settlers came from was at the extreme end of the polynesian expansion and so a very limitied gene selection. Howver there’s no indication that they suffered from problems that prevented them from growing to possibly 13,000 people and a thriving (ultimately self-destructive) civilization. ---
**Author:** ![monstro](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@monstro](https://boards.straightdope.com/u/monstro)\ **Post date:** [August 13, 2012, 6:05pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/42 "2012-08-13T18:05:03Z")
> [@DSeid](#): > > So yes those traits that get measured as intelligence are highly inheritable - the question remains open however if a higher load of those genes results in more intelligence or becomes deleterious at some level resulting in brain dysfunctions or disease susceptibilities. > > [One hypothesis for autism is based on that thought process](http://www.nature.com/news/2011/111102/full/479025a.html): the genes that lead to superiority in various analytic sorts of skills (including those that underlie math ability) when present in larger amounts from _both_ parents result in a higher incidence of autism. Schizophrenia/schizotypy has also been conceptualized along these lines. Except that instead of analytical thinking, creativity is the trait that is believed to be selected for. So in the Utopia, no math geeks or artsy/fartsy people should be allowed. ---
**Author:** ![Darwins\_Finch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darwins_finch/32/20304_2.png) [@Darwins\_Finch](https://boards.straightdope.com/u/Darwins_Finch)\ **Post date:** [August 13, 2012, 6:27pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/43 "2012-08-13T18:27:51Z")
> [@al27052](#): > > Because geniuses aren’t human? > > Dude, come on. Two points: > > 1. The studies _controlled_ for environment. You know, like peer-reviewed studies are SUPPOSED to do. > > 2.The example hinged on the assumption that environment would not vary. Again, controlling for environment. Two points in rebuttal: 1. The ‘controlled’ environment of the studies is not the same as the environment in which this colony would exist, therefore any heritability seen in those controlled experiments cannot be extrapolated to this theoretical colony; 2. Really, that’s the only point that matters. Heritability is not determinism. Heritability is not a genetic guarantee. Heritability is a correlation, nothing more. Further, given that the precise genetics of the actual underlying genome aren’t even fully known, it is simply impossible to state anything about the relative intelligence of this proposed sequestered population over time. Not even 100% heritability is a guarantee of anything. ---
**Author:** ![al27052](https://avatars.discourse-cdn.com/v4/letter/a/41988e/32.png) [@al27052](https://boards.straightdope.com/u/al27052)\ **Post date:** [August 13, 2012, 6:40pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/44 "2012-08-13T18:40:38Z")
> [@Darwins\_Finch](#): > > Two points in rebuttal: > > 1. The ‘controlled’ environment of the studies is not the same as the environment in which this colony would exist, therefore any heritability seen in those controlled experiments cannot be extrapolated to this theoretical colony; > 2. Really, that’s the only point that matters. > > Heritability is not determinism. Heritability is not a genetic guarantee. Heritability is a correlation, nothing more. Further, given that the precise genetics of the actual underlying genome aren’t even fully known, it is simply impossible to state anything about the relative intelligence of this proposed sequestered population over time. Not even 100% heritability is a guarantee of anything. Yes, that’s true. Epigenetics can have a very great effect, as well as just general environmental influences. However, there’s nothing in any scientific study that would lead one to believe there’s any real possibility that environment could pull the average IQ of the hypothetical group back to 100 within, say, 20 generations, without there being serious health consequences. IOW, it’s pretty difficult to lower someone’s IQ through environmental and epigenetic influences without also seriously harming their physical health. We need adequate nutrition and social and intellectual stimulation. Take those away, and, while you might be able to lower the average IQ, you’re also going to mess up a lot of other stuff too. ---
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [August 13, 2012, 8:50pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/45 "2012-08-13T20:50:04Z")
There was a plethora of truly bad studies of the heritablilty of intelligence, largely from the “tabula rasa” crowd in the mid 20th century. More recent carefully controlled studies included the following kinds of studies to discern genetic vs. environmentally heritability: - twins reared apart - fraternal twins - natural siblings vs. adopted siblings According to Steven Pinker’s “The Blank Slate”, genetics accounted for 50% of the variation. Parental/family enviroment accounted for up to 10%. The other 40-50% was unaccountable, and probably due to chance factors in fetal development. These studies also tended to show that while parents can increase the IQ scores of their kids, these differences don’t tend to persist; they fade over a decade or two. If we agree that intelligence is 50% genetic, then the average intelligence of the next generation would be lower, but would stabilize for successive generations. The book I cited above is dated 2002. It is consistent with similar facts cited in Paul Erlich’s “Human Natures”. Research since then might have yielded different results, but would need to be carefully scrutinized for methodology. It’s terribly easy to do misleading research in heritability. ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [August 13, 2012, 11:00pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/46 "2012-08-13T23:00:59Z")
> [@al27052](#): > > If you can find 5 or 6 relevant, peer-reviewed studies on the first page of google results, then yes, it IS reasonable to ask people to do their own googling. Nope. On this MB, it is never acceptable to do that, except maybe in the Pit. In this forum, particularly, you should expect to be able to back up any assertion you make with a cite. ---
**Author:** ![samclem](https://avatars.discourse-cdn.com/v4/letter/s/a9a28c/32.png) [@samclem](https://boards.straightdope.com/u/samclem)\ **Post date:** [August 13, 2012, 11:08pm UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/47 "2012-08-13T23:08:52Z")
I don’t see this question as answerable in General Questions, so I"m moving it to Great Debates to allow greater lattitude in answers., **samclem** , Moderator ---
**Author:** ![Iggy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/iggy/32/3364_2.png) [@Iggy](https://boards.straightdope.com/u/Iggy)\ **Post date:** [August 14, 2012, 12:17am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/48 "2012-08-14T00:17:28Z")
Genome-wide association studies establish that human[intelligence is highly heritable and polygenic](http://www.nature.com/mp/journal/v16/n10/abs/mp201185a.html) > [@](#): > > …Our results unequivocally confirm that a substantial proportion of individual differences in human intelligence is due to genetic variation, and are consistent with many genes of small effects underlying the additive genetic influences on intelligence. [Genetic and environmental influences on adult intelligence and special mental abilities.](http://ukpmc.ac.uk/abstract/MED/9549239/reload=0;jsessionid=oyxwKILBAUyzYyHAnr5L.0) > [@](#): > > I review representative biometric studies of adult twins and adoptees that have been used to generate estimates of genetic and environmental influence on intelligence (IQ) and special mental abilities. The various studies converge on a heritability estimate between 0.60 and 0.80 for IQ. Estimates of common environmental influence from the same studies are near zero. … The messy part is recognizing that in a lot of studies IQ tests are often (and perhaps controversially?) used as a measure of intelligence. You could argue that a correlation is revealed in how well IQ tests are taken and then argue whether that has much of anything to do with a broader idea of intelligence, but that would be a different thread. **TriPolar** seems to be confusing population level effects with individual level effects. There is nothing mutually exclusive about 1)the mean of a trait (height, intelligence, or whatever) being higher in the descendants of a cherry picked founder group and 2)some members of that F1 or subsequent generation being below the old mean. You don’t have to know the genetic cause of the trait in question for this to be so. Suppose you selected all professional basketball players from the NBA (average height 6’7") and WNBA (average height 6’0") and isolated them to start a new population. Take as a given that the average height of these individuals is taller than the average height of the origin population as a whole. Suppose for the sake of example that the average height of all adults in the original source population is 5’10" for males and 5’5" for females. You then come back in 500 years to measure the height of the descendants. The average height of all adults is likely to form a bell curve distribution, with a mean somewhat higher than 5’10" and 5’5" male and female heights of the source population. And that can be true even though there may be some significant part of that population that is shorter than those heights. This expectation is based upon the observed heritability of height being about 0.6 to 0.8 and thus substantially genetically influenced. Genetic heritability of height can be inferred from [twin studies](http://www.ncbi.nlm.nih.gov/pubmed/14624724) with no need to identify specific responsible genes. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [August 14, 2012, 1:19am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/49 "2012-08-14T01:19:25Z")
The answer to this question is that it depends on which selection pressures drive successful reproduction. In general, of course, if you want to breed smarter people you have to keep breeding every succeeding generation selected out for intelligence. That way, you get the smartest genes. However, the original group contains a vast selection of genes, so there is going to be a natural regression toward a less-smart average than the parent pool for the first generation. After that, and for subsequent generations, it depends on what the selection pressure is. At least you have some high-performing genes in the pool, sure, but what if the smart people are best able to take advantage of everyone else and become rich and lazy, and decide kids are too much work, and the dumber people are poorer and harder working, and decide large families are a greater blessing than poverty is a curse? You’ll regress toward a much lower average than if there is selective breeding with high reproduction rates for those with high-intelligence genes. Evolution is about descent with modification, and the descent part is pretty darn important. It is definitely not tied just to intelligence. One can imagine a world where a species gets so smart they manage to wipe themselves out (nukes; AGW;modified viruses…) while the cockroaches still hang out just fine after several hundred million years. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [August 14, 2012, 1:22am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/50 "2012-08-14T01:22:29Z")
So let me see if I understand what seems to actually be the consensus here: A wide variety of cognitive and physical abilities have some degree of genetic basis, some basis in cultural factors from family factors to broader community and societal ones, some other physical environment basis, and some who knows random variation. How much of each for any particular trait or ability is up for some debate. All agreed so far? To the degree that any factor has a genetic contributor the founder effect would mean that the population would be score “higher” in that trait than the originator population. Everything else being equal to the degree that the trait is not genetically based there would be some degree of regression towards (but not completely to) the mean. It of course is improbable that everything else would be equal. A population that consisted of the sigma outliers of abilities and accomplishments would likely be providing an environment more likely to facilitate each child reaching their potential than the originator society did. These are not just kids whose parents are smart and who have a better chance at having the genes associated with intelligence; they are being raised in a family with smart parents and surrounded by people smarter than average, possibly including those better skilled at teaching as well. They are being exposed to the work of the best artists, coached by the best athletes … “Would the total population remain smarter, stronger, etc than the average of the people they left behind?” Well sure. Does that seem reasonable to all? Although I still wonder about adverse effects … [here](http://rspb.royalsocietypublishing.org/content/274/1627/2801.full), for example, is an article going into detail about the association **monstro** mentioned. > [@](#): > > Schizophrenia has also been associated with creativity throughout recorded history (Claridge et al. 1990; Nettle 2001). Diverse evidence from psychological experiments, biographical survey studies and neurophysiology has been accumulating for many years in support of the hypothesis that schizotypal cognition is associated with creativity and divergent thinking (see reviews in Claridge et al. 1990; Nettle 2001, 2006a; Barrantes-Vidal 2004). An untested prediction of this hypothesis is that schizophrenia has evolved, and is maintained, in part as a maladaptive by-product of recent positive selection and adaptive evolution in humans (Crow 1997; Horrobin 1998). … > > … Our results provide evidence for a significantly stronger signal of positive selection specific to the human lineage for schizophrenia-associated genes than for a control set of neuronal activities genes, for both the HapMap-based analyses of recent selective sweeps and the PAML analyses of positive selection. Furthermore, significant evidence of positive selection was found for several genes that exhibit some of the best-replicated and best-understood genetic and functional associations with this disorder, including DISC1, DTNBP1 and NRG1. … > > … Evidence from previous work salient to the hypothesis that the adaptive evolution of genes underlying schizophrenia has involved phenotypic selection comes from studies of genetic linkages between schizophrenia-risk genes and aspects of creativity. Allelic variants of three genes associated with schizophrenia, SLC6A4, TPH1 and DRD2, have recently been associated with measures of creativity and imagination in normal population (Bachner-Melman et al. 2005; Reuter et al. 2006). Notably, the STin2.12 allele of an intronic polymorphism in the SLC6A4 gene and the A allele of the A779C polymorphism in the TPH1 gene are each associated with both increased creativity and increased risk of schizophrenia (Bachner-Melman et al. 2005; Reuter et al. 2006). Alleles of several genes associated with schizophrenia also influence measures of schizotypal cognition and ‘openness to experience’ in non-clinical populations, including COMT and HTR2A (Ott et al. 2005), MAOA (Samochowiec et al. 2004) and SLC6A4 (Golimbet et al. 2003). Description of the linkages of creativity and cognition with schizotypy and schizophrenia is provided for the four genes, SLC6A4, TPH1, COMT and DRD2, with sufficient integrative information available for detailed analysis (electronic supplementary material). We also describe here the neurological and psychological evidence that links schizotypy with aspects of creativity and divergent thinking, and epidemiological data for variation in measures of fitness between schizophrenics, first-order relatives and controls. > > The mechanisms connecting schizotypal cognition and creativity with postulated fitness benefits are unclear, but may include sexual selection, creative and artistic skills, or general benefits from insight problem solving (Shaner et al. 2004; Nettle 2006a; Karimi et al. 2007). Such processes could potentially help to explain the paradoxical high heritability and persistence of schizophrenia, owing to some combination of multilocus balancing selection, antagonistic pleiotropy affecting fitness and mutation–selection balance. > > We stress that enhanced creativity is not expected to be a function of schizophrenia itself (which involves profound cognitive impairments), but rather is inferred to be a function of schizotypal cognition (Claridge et al. 1990; Nettle 2001, 2006a,b; Barrantes-Vidal 2004). Indeed, alleles underlying the deleterious aspects of schizophrenia or schizotypal cognition are expected to be selected against (Keller & Miller 2006; Nettle 2006b). We also note that most studies of the cognitive correlates of genetic liability to schizophrenia have focused on documenting deficits in clinical populations, rather than testing for potentially positive aspects of cognition in healthy relatives or other individuals who carry schizophrenia-associated alleles or genotypes. The parallel with Bar-Cohen’s autism hypothesis are indeed strong. A little is good; too big a load is deleterious. (Similarly with sickle cell, one allele protects from malaria, two causes a bad disease). Concentrating those genes may have unforeseen adverse consequences. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [August 14, 2012, 1:29am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/51 "2012-08-14T01:29:46Z")
> [@Sunspace](#): > > … thus ensuring the next generation of athletes. Off-topic, but did they run out of their 100,000 condoms (or did the organizers forget to order magnums), or what? ETA: your article says they did, but I think the ESPN article might have gotten it more correct… ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 14, 2012, 1:34am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/52 "2012-08-14T01:34:40Z")
> [@Iggy](#): > > **TriPolar** seems to be confusing population level effects with individual level effects. There is nothing mutually exclusive about 1)the mean of a trait (height, intelligence, or whatever) being higher in the descendants of a cherry picked founder group and 2)some members of that F1 or subsequent generation being below the old mean. You don’t have to know the genetic cause of the trait in question for this to be so. I understand what you are saying. And I think anybody would assume that the most likely outcome of selection for traits is to see those traits remain or enhanced. But intelligence may be more complex than height as a trait, and there are a variety of reasons to consider in the OPs scenario that there may be no enhancement of intelligence over time. I think it requires more specific indicators that there would be significant increase in intelligence in this group in the end. I certainly didn’t say anything about it being impossible. I don’t even know what **al27052** is arguing about. My responses to him were directed at his statements that never seemed to relate to my original post. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 14, 2012, 1:48am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/53 "2012-08-14T01:48:43Z")
> [@TriPolar](#): > > Since the basis for forming the group wasn’t heritable intelligence, **there may be no effect at all.** Perhaps I was not clear there and someone thinks I meant that intelligence would regress, but I only meant there might be no increase in intelligence on average as an effect. That would apply to my use of individual examples as well, to explain why intelligence might not increase over time for individuals, not to say that it would decrease across the population over time. But I also think that selecting the most measurably intelligent people on earth would tend to pick up outliers who wouldn’t necessarily pass the genes for such super intelligence to their children. 100,000 people is a tiny percentage of the world population who’s intelligence level may be so high and have occurred as a result of a variety of factors that may not reproduce easily, and it’s entirely possible there would be an average decrease in the first generation. This is the difference between picking from NBA players, and the tallest people on earth. ---
**Author:** ![Steve\_MB](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steve_mb/32/5339_2.png) [@Steve\_MB](https://boards.straightdope.com/u/Steve_MB)\ **Post date:** [August 14, 2012, 2:44am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/54 "2012-08-14T02:44:27Z")
There’s also the issue of “what kind of ‘smarter’”? A rocket scientist guy who couldn’t spot a mating opportunity if a girl gave him her phone number written on a no-tell motel business card? A gal who could build a rocket out of a box of scraps in a cave and then break it down and mail it to somebody in Nigeria who is offering the former dictator’s bank account in trade? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 14, 2012, 3:32am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/55 "2012-08-14T03:32:05Z")
> [@Steve\_MB](#): > > There’s also the issue of “what kind of ‘smarter’”? A rocket scientist guy who couldn’t spot a mating opportunity if a girl gave him her phone number written on a no-tell motel business card? A gal who could build a rocket out of a box of scraps in a cave and then break it down and mail it to somebody in Nigeria who is offering the former dictator’s bank account in trade? That is a problem in this discussion. We have to assume the measure is consistent, and there should be some strong evidence that the trait can be inherited. ---
**Author:** ![al27052](https://avatars.discourse-cdn.com/v4/letter/a/41988e/32.png) [@al27052](https://boards.straightdope.com/u/al27052)\ **Post date:** [August 14, 2012, 3:52am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/56 "2012-08-14T03:52:18Z")
> [@Chief\_Pedant](#): > > The answer to this question is that it depends on which selection pressures drive successful reproduction. In general, of course, if you want to breed smarter people you have to keep breeding every succeeding generation selected out for intelligence. That way, you get the smartest genes. > > However, the original group contains a vast selection of genes, so there is going to be a natural regression toward a less-smart average than the parent pool for the first generation. After that, and for subsequent generations, it depends on what the selection pressure is. At least you have some high-performing genes in the pool, sure, but what if the smart people are best able to take advantage of everyone else and become rich and lazy, and decide kids are too much work, and the dumber people are poorer and harder working, and decide large families are a greater blessing than poverty is a curse? You’ll regress toward a much lower average than if there is selective breeding with high reproduction rates for those with high-intelligence genes. > > Evolution is about descent with modification, and the descent part is pretty darn important. It is definitely not tied just to intelligence. One can imagine a world where a species gets so smart they manage to wipe themselves out (nukes; AGW;modified viruses…) while the cockroaches still hang out just fine after several hundred million years. This is a good point. We know a random pattern of reproduction would produce a partial regression to the mean. The question is, what would evolution, given a very similar environment as the rest of humanity, do to the bell curve for this special population? Move it even closer to the mean, farther from the mean, or have little noticeable effect? ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 14, 2012, 4:04am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/57 "2012-08-14T04:04:16Z")
> [@al27052](#): > > This is a good point. We know a random pattern of reproduction would produce a partial regression to the mean. > > The question is, what would evolution, given a very similar environment as the rest of humanity, do to the bell curve for this special population? Move it even closer to the mean, farther from the mean, or have little noticeable effect? How long are you talking about? And is this population growing? There should be some idea of what happens to general characteristics over time. Also, you should be happy to know that after doing a little math which I should have done before, I see that the top 100,000 people would be 1 in 70,000 people, which wouldn’t be a bunch of extreme outliers. So you’re right that this population should expect to follow a predictable pattern based on the general heritability of the trait. But do you know of something that would indicate the level of intelligence would increase in a group already selected for high intelligence? ---
**Author:** ![al27052](https://avatars.discourse-cdn.com/v4/letter/a/41988e/32.png) [@al27052](https://boards.straightdope.com/u/al27052)\ **Post date:** [August 14, 2012, 4:16am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/58 "2012-08-14T04:16:54Z")
> [@TriPolar](#): > > How long are you talking about? And is this population growing? There should be some idea of what happens to general characteristics over time. How long? Maybe 60-70 generations. For the sake of the example, we’ll say no, the population isn’t growing or shrinking (although that is a good question, and I agree that it might have multiple effects on different levels). > [@TriPolar](#): > > Also, you should be happy to know that after doing a little math which I should have done before, I see that the top 100,000 people would be 1 in 70,000 people, which wouldn’t be a bunch of extreme outliers. So you’re right that this population should expect to follow a predictable pattern based on the general heritability of the trait. But do you know of something that would indicate the level of intelligence would increase in a group already selected for high intelligence? No, I doubt they would become even more intelligent. I am open to the possibility that there might be a “tipping point”, though, above which the average person is so intelligent that…well, I don’t know, but I refuse to discount the possibility, anyway, at this point. I might later, though. And I believe the original number was 1000, not 100,000. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [August 14, 2012, 4:27am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/59 "2012-08-14T04:27:36Z")
> [@al27052](#): > > And I believe the original number was 1000, not 100,000. Well if it was 1000 I think you be selecting a lot of extreme outliers. But the OP said “a few hundred thousand people from the top 1% of humanity” so that’s an even better selected group than I thought the second time around. ---
**Author:** ![al27052](https://avatars.discourse-cdn.com/v4/letter/a/41988e/32.png) [@al27052](https://boards.straightdope.com/u/al27052)\ **Post date:** [August 14, 2012, 5:06am UTC](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341/60 "2012-08-14T05:06:24Z")
> [@TriPolar](#): > > Well if it was 1000 I think you be selecting a lot of extreme outliers. But the OP said “a few hundred thousand people from the top 1% of humanity” so that’s an even better selected group than I thought the second time around. Yeah, I’m wondering how socially functional the top 1000 even are. Can they mate? ROFL [Previous page](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341.md?page=2) [Next page](https://boards.straightdope.com/t/select-only-smart-people-for-a-colony-do-their-descendants-remain-smart/631341.md?page=4)