All of harpend's Comments + Replies

Food for her and to support a ritual gathering of folks for support. There is no medical care out in the bush, but if there were people would certainly chip in to help pay for it.

HCH

Yes, of course, I will give you that. You are suggesting that "time preference" is way too global and vague a concept and I can't disagree.

HCH

They could certainly imagine investing: they have been invaded by cattle people over the last half century and they see husbandry all around. And they certainly could have afforded to keep their animals. But they just didn't (seem to) have it in them to "delay gratification". I think that our ability to invest and save resources must be new and different in our evolution.

I don't agree with you except a little bit. And there are foragers who do have some low time preference, like on the US Northwest Coast where they harvested lots of salmon that they smoked and stored. Interior Eskimo slaughtered migrating caribou herds and stored the meat by freezing.

But in general forager life has been almost literally hand to mouth. I have spent a lot of wasted time pulling my hair out about this. We have had lots of Bushman employees in the Kalahari, well compensated. We have spent hours pointing out that we would go back to Americ... (read more)

I am trying to think about the genesis and maintenance of social class and about the dimensionality of class. We know from the biometricians at the end of the nineteenth century that cognitive ability is essentially a single dimension while athletic ability, for example, is multidimensional. I want to start with a pure inductive approach to class in North America and do the same thing with class. Fat chance, I have found, since every time I get started I get sucked back into genetics.

Henry

I think Greg's 'biologists' are a special subset of biologists. As I see it CP Snow was right about the two cultures. But within science there are also two cultures, one of whom speaks mathematics and the other that speaks organic chemistry. Speaker of organic chemistry share a view that enough lab work and enough data will answer all the questions. They don't need no silly equations.

In our field the folks who speak mathematics tend to view the lab rats as glorified techs. This is certain not right but it is there and leads to a certain amount of mutu... (read more)

I don't know but I can give you some candidates. One is torsion spasm (Idiopathic Torsion Dystonia). It will give you about a ten point IQ boost just by itself. Most of the time the only effect of the disease is vulnerability to writer's cramp, but 10% of the time it puts you in a wheelchair. So you could do science just fine.

Similarly the Ashkenazi form of Gaucher's disease is not ordinarily all that serious but it also give a hefty IQ boost. Asperger like stuff would probably also increase: many super bright people seem to be a bit not quite. Of course lots of other super-brights seem to be completely normal.

I am just babbling, I have no special insight at all...

HCH

When I did fieldwork in the late 1960s in backcountry Botswana I hit upon the idea of asking my sister (a dairy farmer) to send me a box of back issues of American cattle magazines. It was unbelievable: I could have made a fortune selling pictures from them, not to mention whole issues, to the local cattle people. At that time people carefully hoarded little scraps of paper to use writing messages.

In the late 1980s I brought some more such magazines with me, and no one was interested at all. The media storm had penetrated and everyone had school textbooks, magazines, radios, etc.

Can you elaborate your comment--sounds fascinating. HCH

I have no further knowledge or insight about that, but Greg might. I will call this question to his attention and we may see what he knows.

HCH

There is apparently a research group in China that has some solid results but I have not seen them and do not know if they are out yet.

HCH

Yes, of course. But remember that in science we are not in the business of "accepting" one thing of another. That is the domain of religion and politics. The only thing that matters is finding good hypotheses and testing them.

HCH

It must be simple in some way since it is so heritable. People with IQs of 90 and IQs of 140 both prosper and do fine. although there are lots of statistical differences between two such groups.

Other other hand if we take a trait like "propensity to learn language in childhood" this seems to me to be relatively invariable and fixed and so probably very complex.

Certainly one could breed for IQ and raise the population mean a lot. But what would we be doing to our children? People with 140 IQ seem to do all right but I would worry a lot about the kind of life a kid with an IQ of 220 would have.

My feeling is that the dichotomy between societies where males are threatening and violent and societies where males are submissive and not threats to each other is the most interesting social dichotomy we have. In some societies where males are threats there is a clear alternative niche like the Berdache on the Great Plains. In urban ghettos with drug dealers and street corner males there is a significant set of males who hold down jobs and, often, bring the proceeds to support their matrifocal families. How much such males reproduce is not clear. A w... (read more)

I have heard discussion about the singularity on the web but I have never had any idea at all what it is, so I can't say much about that.

I do not think there is much prospect for dramatic IQ elevation without producing somewhat damaged people. We talk a lot in our book about the ever-present deleterious consequences of the strong selection that follows any environmental change. Have a look for example at the whippet homozygous for a dinged version of myostatin. Even a magic pill is likely to do the same thing. OTOH scientists don't have a very good track record at predicting the future. Now, I am going to hop into my flying car and go to the office -:)

HCH

It is an interesting puzzle. This was a secular rise in cognitive test scores well documented in a number of countries during the 20th century. It has stopped and even reversed in the last few decades. There seem to be several pausible ideas out there

One is that social changes have had the effect of "training" people for cognitive tests: more magazines, radio, chatter everywhere, advertising, etc. Hard idea to test. I do fieldwork in Southern Africa. Forty years ago there were no radios in the backcountry, no books, no magazines. Today ra... (read more)

Right, wolves pack-hunt which involves pretty complex management of prey herds including something like a "theory of prey mind" to predict what the prey will do.

There is a lot known about cape dog hunting because they are in fairly open country and can be observed. Not only do they predict where the prey herd will go, they coordinate and signal to each other with postures during the chase. It is absolutely beautiful to watch, like stop-action ballet.

HCH

You are even meaner than Shulman. We don't know how human intelligence evolved and we need to know it in order to answer your question I think. This is where evolutionary psychology and differential psychology (Am I using that term right?) must come together to work this out.

We think that we know a little bit about how to raise intelligence. Just turn down the suppression of early CNS growth. If you do that in one way the eyeball grows too big and you are nearsighted, which is highly correlated with intelligence. BRCA1 is another early CNS growth su... (read more)

Yikes! This is worse than my PhD orals.

There have been some (tentatively) identified like the 7-repeat version of the D4 dopamine receptor, the serotonin transporter, and others that Greg will be able to dredge up from his memory.

We may have found others but not identified them. Imagine that it would be highly beneficial to have a little bit less of substance s. If so then a mutation that broke the gene producing s would be favored a lot and would sweep until people with two copies of broken s started being born. How likely is it now that two broken ... (read more)

That is a big and interesting question. I do not think that evolutionary biology needed more math at all: they would have done better with less I think. The only math needed (so far) in thinking about acceleration is the result that the fixation probability of a new mutant is 1/2N if it is neutral and 2s if it has selective advantage s. The other important equation is that the change in a quantitative trait is the product of the heritability and the selective differential (the difference between the mean of the population and the mean of parents).

The h... (read more)

I think your perception is correct, but I am no expert. I sense that evolutionary psychologists are really interested in human universals: the famous experiments of Tooby and Cosmides go right to that point. Why are we all afraid of snakes? Why are our babies do hard to toilet train? But they generally don't have a lot to say about variation among humans in these traits.

The other sort that you and I both perceive are interested in human diversity and aren't much concerned with the bigger questions of the ev psych people.

No, they don't "play nice... (read more)

And thank you all for the honor of your invitation.

HCH

Hi Carl:

No word on that yet. They identified regions of the genome where there are (1) deep gene trees in Europe and/or Asia, (2) we share variants with Neanderthals, and (3) these shared variants are absent in Africa, and they found a lot of them. But if some variants in Neanderthals were positively selected in humans very early on then they would have spread through all humanity, and no one has scanned for those yet.

Our favorite candidate is the famous FOXP2 region, without which one has no speech. Every human has it, and the diversity hear it on t... (read more)

Very nice summary--thanks.

@SilasBarta:re our careers:

I would certainly never encourage a graduate student to follow up in this area because it would be a career kiss of death. But I am at retirement age, no one is going to fire me, and most important of all I do not have federal grant support. Cochran is not an academic: his real career is in laser physics. So we enjoy a kind of freedom that few academics do.

@JanetK re skin color:

According to standard ag-sci 101 theory the number of loci makes no difference at all to the speed of change of a multi-locus... (read more)