
Chimpanzee Intelligence Is Heritable [pdf] - gwern
https://pdf.yt/d/0MSB48zQSooDz5Zw
======
ytturbed
Fascinating stuff but the concept of intelligence is rather nebulous. Their
operational definition is cobbled together from things that people have
intuitively considered important like eye tracking and tool use. But these
aren't connected to any deeper explanatory theories. Personally I'd be
inclined to selectively breed chimps on the basis of how well they _follow
instructions_ (since instructions are perforce couched in abstract symbols and
language is the quintessentially human trait).

~~~
jsnk
I feel like every chatter about intelligence comes down to arguing over the
operational definition of intelligence. Isn't it obvious that abilities such
as simple arithmetics, memory, linguistic ability, recognizing patterns have
at least something to do with intelligence?

~~~
ytturbed
No, it's not obvious. If it were then we'd have programmed an AGI by now.

~~~
JamesArgo
So basically, we can't make a photodetector without first being able to create
a sun?

~~~
ytturbed
We can't measure things we don't understand. Note that a photodetector detects
light, not suns.

~~~
JamesArgo
>We can't measure things we don't understand.

What? Was everyone blind before the discovery of quantum mechanics? If we
can't measure things we don't understand, how the heck would we come to
understand them? Through their affects on the world? "No, you say, "we can not
perceive things whose causes we don't understand." Where did you get your
epistemology? Was it The Secret?

~~~
ytturbed
>Where did you get your epistemology?

Karl Popper.

>If we can't measure things we don't understand, how the heck would we come to
understand them?

We get new ideas, such as the concept of distance, by guessing them in
response to problems.

------
lumberjack
Slightly related but I always wondered why is it that children of geniuses
rarely if ever reach the same level of accomplishment as their parent(s)
despite having a better chance over all than their genius parent(s) had.

~~~
dnautics
[https://en.wikipedia.org/wiki/Regression_toward_the_mean](https://en.wikipedia.org/wiki/Regression_toward_the_mean)

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tormeh
How is this stuff still controversial?

~~~
api
For the same reason that evolution, global warming, the historical study of
religion, etc. are controversial: it conflicts with popular political beliefs
and leads to taboo discussions.

It's taboo to both the left and the right. Both like to pretend differences in
innate ability don't exist. The left likes to explain disadvantage exclusively
as a socially constructed phenomenon that can be remedied through social
engineering. The right likes to chalk it up to laziness or moral corruption,
arguing that the disadvantage more or less deserve it.

If it's biological to any significant degree, they're both wrong. It's
heritable, so no amount of social engineering will fix it, and it's also not a
result of chosen moral deficiencies or laziness so it's not a moral failing.
Being born with a lower IQ is no more your fault than being born without an
arm.

It also leads to taboo discussions around wealth distribution. If our success
rates are largely a result of our success at winning the genetic lottery, can
you morally justify really massive levels of wealth inequality? Is it just
that random initial conditions completely dictate outcome?

If intellectual ability is largely heritable, then both the left's PC
moralizing and the right's Calvinist moralizing are bullshit.

I've toyed around with the concept of a kind of transhumanist socialism in
which these kinds of enhancements -- both germ-line and for already living
people -- would be made universally available to everyone. I wonder to what
extent the failure of socialist schemes is the result of their technical
inability (or unwillingness) to address the root causes of inequality. Use a
progressive income tax not to fund the zero-sum redistribution of wealth, but
the positive-sum redistribution of _ability_. Transform humanity into a
"runaway self-improving AI."

As far as I know, virtually everyone in every political persuasion or "wing"
would be horrified by that concept. Given what garbage pretty much all of
today's political discourse is, it kinda makes me think I'm onto something.

~~~
jqm
Very good explanation. I think you are spot on. It's funny how ideology so
often flies in the face of reality and comes back full circle to resemble it's
opposite.

~~~
api
I sometimes wonder if politics is biased toward this kind of thing, since much
of politics is about finagling advantage. Truth, fact, and reality offers
little opportunity for deception, duplicity, and issue smuggling.

------
dengnan
This is off topic: Is it the typical length of a biological paper? I mean in
computer science field, a full paper would be 10~14 pages. Composed of 5~7
pages of experiment results. On the other hand, this paper only contains one
table of result and a figure with quite large fonts. I would like to know if
this is normal in this field?

Edit: typo

~~~
gwern
It really depends on the journal and format. I've seen some very long articles
and also biology articles in Nature which are maybe 2 pages, including
references in teen-tiny font (and nigh-incomprehensible).

In this case, there's something similar: a lot of the information a CS paper
might include inline has been shunted aside to "Supplemental Information
includes one figure, three tables, and Supplemental Experimental Procedures
and can be found with this article online at
[http://dx.doi.org/10.1016/j.cub.2014.05.076](http://dx.doi.org/10.1016/j.cub.2014.05.076)
", and much of the background here (eg the development of the test battery) is
in previous papers. This is more reporting the apex of their work, if you
will.

------
Humjob
Very interesting. This topic has some rather pertinent parallels to our
current civilization.

Suppose:

a) Human intelligence is heritable.

b) Less intelligent humans are more fertile than their brighter peers.

c) The breeding of the less intelligent is subsidized by society over a long
period of time.

What are the long term consequences going to be? I'd bet Peter Thiel has
secretly considered this among his theories of why innovation has slowed, but
wouldn't dare say so in public.

~~~
JamesArgo
>Human intelligence is heritable.

This is indisputable. Denying IQ and its heritability is equivalent to denying
global warming. It’s settled science. Dysgenics is certainly possible. I think
technology like iterated embryo selection and genetic engineering will come
into common use before dysgenics kicks in. China is already investigating
these possibilities, and their culture does not have the same memetic immune
response to such ideas. After one country makes it legal, competitive
pressures will force the rest of the world to do it, too. Iterated embryo
selection could conservatively raise IQ by 60 points, likely much much more:
[http://www.nickbostrom.com/papers/embryo.pdf](http://www.nickbostrom.com/papers/embryo.pdf)

A government would have to be supernaturally incompetent to allow such a gap
to develop.

~~~
vixen99
With you on IQ but 'settled science' & 'denying global warming'? You evidently
enjoy cliches. I don't know anyone on
[http://wattsupwiththat.com/](http://wattsupwiththat.com/) or other respected
sceptical sites who says there's been no warming this and last century and
that it's not partly related to CO2 levels. Anyway, here's a cliche for the
collection: 'If you can't explain the 'pause', you can't explain the
cause...". Where's the settled science there?

As well to remember that address to the British Association for the
Advancement of Science in 1900, when (probably) Lord Kelvin - he, of degrees
absolute, remarked "There is nothing new to be discovered in physics now. All
that remains is more and more precise measurement.". Meanwhile a bloke called
Planck ...

------
tokenadult
I read this article earlier when it was first published. I have also read most
of the prior literature cited in the article's references. A review article,
by some of the same authors the article kindly submitted here cites, gets at
the nub of the issue.

"Moreover, even highly heritable traits can be strongly manipulated by the
environment, so heritability has little if anything to do with
controllability. For example, height is on the order of 90% heritable, yet
North and South Koreans, who come from the same genetic background, presently
differ in average height by a full 6 inches (Pak, 2004; Schwekendiek,
2008)."[1]

It is completely unremarkable that chimpanzee studies show "heritability" for
what counts as intelligence (by this study's model) among chimpanzees. In
general, for any trait, closely related individuals show a stronger
resemblance than less closely related individuals, and that is what
"heritability" means, nothing more. Eric Turkheimer (one of the authors cited
in the article submitted here, and a co-author of the review article I have
just quoted and cited) declared as the "first law of behavior genetics" that
all human behavioral characteristics are heritable, and that is very close to
being literally true. But he also writes, in a later commentary article,
"Heritability isn't an index of how genetic a trait is. A great deal of time
has been wasted in the effort of measuring the heritability of traits in the
false expectation that somehow the genetic nature of psychological phenomena
would be revealed. There are many reasons for making this strong statement,
but the most important of them harkens back to the description of heritability
as an effect size."[2]

The chimp research is interesting, and I suppose other researchers will try to
replicate or refine it, but it still leaves us a long way from understanding
the genetics of human intelligence. Human intelligence is indubitably
influenced by hundreds of genes, each of small effect size, and many with
unknown pleiotropic effects. We are so far nowhere near understanding what
genes do to influence human intelligence.

"At the time most of the results we attempted to replicate were obtained,
candidate-gene studies of complex traits were commonplace in medical genetics
research. Such studies are now rarely published in leading journals. Our
results add IQ to the list of phenotypes that must be approached with great
caution when considering published molecular genetic associations. In our
view, excitement over the value of behavioral and molecular genetic studies in
the social sciences should be tempered—as it has been in the medical
sciences—by an appreciation that, for complex phenotypes, individual common
genetic variants of the sort assayed by SNP microarrays are likely to have
very small effects. Associations of candidate genes with psychological traits
and other traits studied in the social sciences should be viewed as tentative
until they have been replicated in multiple large samples. Doing otherwise may
hamper scientific progress by proliferating potentially false results, which
may then influence the research agendas of scientists who do not appreciate
that the associations they take as a starting point for their efforts may not
be real. And the dissemination of false results to the public risks creating
an incorrect perception about the state of knowledge in the field, especially
the existence of genes described as being 'for' traits on the basis of
unintentionally inflated estimates of effect size and statistical
significance."[3]

Meanwhile, we know that even monozygotic ("identical") twins can be discordant
for IQ or for any other human behavioral trait (this observation is also
called a "law of behavior genetics"), so the one thing we can be sure of is
that something other than genes matters for the expression of absolutely every
trait that a human being can have. This being well known, those of us who have
already received our shuffle of genes may as well devote time, money, and
effort to finding out what environmental factors may help us engage in
problem-solving about important human problems.

[1] Johnson, Wendy; Turkheimer, Eric; Gottesman, Irving I.; Bouchard Jr.,
Thomas (2009). Beyond Heritability: Twin Studies in Behavioral Research.
Current Directions in Psychological Science, 18, 4, 217-220

[http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...](http://people.virginia.edu/~ent3c/papers2/Articles%20for%20Online%20CV/Johnson%20\(2009\).pdf)

[2] Turkheimer, E. (2008, Spring). A better way to use twins for developmental
research. LIFE Newsletter, 2, 1-5.

[http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...](http://people.virginia.edu/~ent3c/papers2/Articles%20for%20Online%20CV/Turkheimer%20\(2008\).pdf)

[3] Chabris, C. F., Hebert, B. M., Benjamin, D. J., Beauchamp, J., Cesarini,
D., van der Loos, M., ... & Laibson, D. (2012). Most reported genetic
associations with general intelligence are probably false positives.
Psychological science, 23(11), 1314-1323. DOI: 10.1177/0956797611435528
[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498585/](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498585/)

[http://dash.harvard.edu/bitstream/handle/1/9938142/Most_Repo...](http://dash.harvard.edu/bitstream/handle/1/9938142/Most_Reported_Genetic.pdf?sequence=1)

~~~
gwern
> But he also writes, in a later commentary article, "Heritability isn't an
> index of how genetic a trait is. A great deal of time has been wasted in the
> effort of measuring the heritability of traits in the false expectation that
> somehow the genetic nature of psychological phenomena would be revealed.
> There are many reasons for making this strong statement, but the most
> important of them harkens back to the description of heritability as an
> effect size."[2]

It is true that heritability does not logically imply immalleabillity. But,
leaving aside the many cases of untreatable or fatal genetic diseases as
possibly too easy, I am struck by how often heritability _does_ turn out to be
about traits which are difficult or impossible to change; we are familiar with
the case of intelligence, of course, but it shows up almost anywhere
heritability does. Consider the case of politics: political affiliation is
highly stable over lifetimes, impenetrable to argumentation, people will tie
themselves in knots to preserve their beliefs (consider the people who argue
that WMDs were successfully found in Iraq), increasingly linked to fundamental
differences in cognition (see
[https://news.ycombinator.com/item?id=8512400](https://news.ycombinator.com/item?id=8512400)
) - and political attitudes are highly heritable
([https://news.ycombinator.com/item?id=8512399](https://news.ycombinator.com/item?id=8512399)
/
[https://news.ycombinator.com/item?id=8504593](https://news.ycombinator.com/item?id=8504593)).
This pattern pops up over and over again: if a study calculates the
heritability of a number of traits, the traits which are high on heritability
and low on shared environment will strike one as things which are hard to
change. If you don't like attitudes or politics or intelligence, consider
personality like the Big Five construct: OCEAN are all highly heritable (~40%
avg), and yet, largely unchangeable. Do you know any way to increase
Conscientiousness aside from dopaminergic stimulants? I don't. Do you know any
way to increase Openness besides possibly psychedelics? I don't. And so on.

> Associations of candidate genes with psychological traits and other traits
> studied in the social sciences should be viewed as tentative until they have
> been replicated in multiple large samples. Doing otherwise may hamper
> scientific progress by proliferating potentially false results, which may
> then influence the research agendas of scientists who do not appreciate that
> the associations they take as a starting point for their efforts may not be
> real. And the dissemination of false results to the public risks creating an
> incorrect perception about the state of knowledge in the field, especially
> the existence of genes described as being 'for' traits on the basis of
> unintentionally inflated estimates of effect size and statistical
> significance."[3]

It would be nice if, in your constant citation of Chabris, you would
incorporate any of the information I've given you in my other replies to you.

~~~
tokenadult
As Alan S. Kaufman wrote in each edition of his textbook _Assessing Adolescent
and Adult Intelligence_ (I read the first edition in the early 1990s), what
you and I don't know about effective environmental interventions to raise IQ
does not at all imply that none existence. It's not valid to argue from
ignorance that something that hasn't been tried cannot possibly work. Kaufman
took care in the first edition of his textbook to point out that we were by no
means sure in that era what was causing the Flynn effect (we still aren't
completely sure about that). But he also noted that it is logically quite
possible that we will discover environmental influences to boost IQ (or, more
importantly, boost actual human achievement outside the testing room) that are
well within our control as we engage in further research.

~~~
gwern
> It's not valid to argue from ignorance that something that hasn't been tried
> cannot possibly work.

Again, it's not deductively logically valid, but it is most certainly
inductively and statistically valid, and _those_ are the validities that
concern us: absence of evidence is evidence of absence, and for few things is
there a more glaring absence than for intelligence boosts. After a century of
formal pursuit, what do we have to show for it? A few very early childhood
interventions like iodine; some interventions one should trust as far as one
can kick them like dual n-back; and some stimulants offering temporary boosts
(but are they boosting actual peak intelligence or just affecting
motivation?).

~~~
barry-cotter
Why are you still operating on the principle of charity with tokenadult? He
has refused to engage with a stable of similar arguments for years, from. He
varies between arguing like he was trained for getting his J.D. (arguments as
soldiers, argument from authority, argumentum ad hominem) and arguing as he
would have during his math degree, by exclusion and contradiction, as
convenient for his ideology.

He's obviously well acquainted with the literature, witness his perennial work
sample test bit but he places radically different burdens of proof on
ideologically convenient and inconvenient arguments.

