Archive for February, 2007

Drink whole milk, get pregnant

By Razib Khan | February 28, 2007 12:10 pm

A story just came out today about drinking high fat vs. low fat milk, and the positive effect on fertility that the former can have. Remember the report that drinking milk increases twinning? Issues like this should be kept in mind when considering the spread of lactose tolerance, anything that increases fitness should spread. Why didn’t it? Well, it seems likely that cattle can’t be raised everywhere, so you have a situation where the selective benefit is geographically constrained. Also, modern lifestyles are characterized by no scarcity of calories so comparing this to pre-modern situations might be a false trail. The world wide spread of milk consumption should be changing things genetically though….

CATEGORIZED UNDER: Biology

Recent Human Evolution in the house

By Razib Khan | February 27, 2007 10:23 am

Early man ‘couldn’t stomach milk’

Working with scientists from Mainz University in Germany, the UCL team looked for the gene that produces the lactase enzyme in Neolithic skeletons dating between 5480BC and 5000BC.
These are believed to be from some of the earliest farming communities in Europe.
The lactase gene was absent from the DNA extracted from these skeletons, suggesting that these early Europeans would not be tolerant to milk.

The paper will be Absence of the Lactase-Persistence associated allele in early Neolithic Europeans in PNAS. First LCT, then OCA2, and god knows what else? There is a limit in terms of what you can do with archeoDNA, but if the action went down in the last 10,000 years then it isn’t such a sweat.
One thing, the summary in Science is weird. Check it:

The culture-historical hypothesis is that, shortly after the domestication of livestock, a few lucky farmers with a genetic anomaly hit white gold: nourishment via milk. Then, according to this theory, natural selection took over and these lactase-persistent folks proceeded to populate much of Europe with their milk-guzzling offspring. A competing hypothesis argues that ancient Europeans domesticated milk-bearing livestock because lactase persistence was already quite common in certain populations.

Quite common? The area of the genome around LCT was hit by a hammer blow of selection less than 10,000 years ago, that’s why researchers use it to check if their methods for detecting selection are working. The fact that independent events of lactase persistence exist among other populations via alternative genetic architectures seems to indicate clearly the power of gene-culture coevolution. What’s up with Science doing a “look at both sides” framework when the evidence is so lopsided? I suppose selection could have been induced by a causative factor aside from milk, but I think we’re verging into Humean skepticism at this point, denying the ability to discern causality at all….
Carl Zimmer has much more….
Related: Lactose tolerance by a different stroke. Lactose tolerance/intolerance. Are multiple lactose tolerance mutations surprising? Genes & culture & milk. Lactose tolerance, is it “dominant”? Milk digestion, it does a body good.

CATEGORIZED UNDER: Genetics

Buddhism, a religion or not?

By Razib Khan | February 26, 2007 10:44 am

The comments for the post where I imply that Sam Harris is a religiously inclined individual addressed the topic of whether Buddhism is a religion or not. This is a common issue, and I tend to cause some irritation whenever I declare that Buddhism is a theistic religion, because that’s not what you would read in books (or, Wikipedia). I’m generally a big fan of what books have to say, and defer to scholars in areas that I’m not familiar with, but, I’ve really come to the point where I simply don’t think that Religious Studies really adds enough intellectual value for me. Christians believe in the Trinity, Buddhists reject a Creator God, Hindus believe in reincarnation, etc. etc. But what does this really mean on the human level? Because I don’t really believe that supernatural belief systems have any reality outside of the minds of human beings. They are cognitive representations, nothing less, nothing more.
A little book titled Theological Incorrectness: Why Religious People Believe What They Shouldn’t, lays out most of the issues that I find of interest and curious about modal religious belief. The biggest one is that religious people don’t really take their axioms of belief and embed them into a chain of inferences guided by propositional logic. That is, secularists are always wondering why religious people who “believe” x nevertheless behave in ways 1…∞” that seem to contradict their avowed beliefs. For example, when I read about Saudi men gang-raping a woman and videotaping it, when they believe in a just and merciful God that is observing this, one has to wonder what’s going on in the human mind? Religious people regularly engage in this sort of psychology as well, “x couldn’t have been committed by Muslims, because Muslims don’t, by definition, do such things.” Or, “y wasn’t a real Christian, because if you really believed in God you wouldn’t behave in such a manner.” I’ve even seen strange definitions like “de facto atheists” for people who avow a belief in a divine entity but behave in an amoral fashion. Now isn’t that charming?

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CATEGORIZED UNDER: Religion

Cultural selection….

By Razib Khan | February 25, 2007 1:21 pm

John Emerson has a long post about the relationship between irrationality and the emergence of new cultural forms. Worth reading. The other day I had a thought: many cultural traits are basically hitch-hiking along. Consider circumcision and the ban against pork consumption for Muslims, in places like Indonesia when tribes convert to Islam they abandon their pigs and circumcision becomes the norm. Why? People have been inventing strange functional rationales for these customs for decades. It seems likely that these practices have a role as ingroup vs. outgroup markers, that is, they’re convenient shibboleths. Food taboos of course impose segregation between different groups if they can’t eat together without transgressing their norms (e.g., Muslims eating at a Chinese house often have issues because of the ubiquity of pork). That being said, an interesting model for the “selection” of shibboleths is that the group in which cultural form or religion x arose tend to serve as a model, and so all sorts of peculiar customs spread outward. For Islam, circumcision and the non-consumption of pork would qualify (circumcision is actually not even a religious sacrament in Islam as it is in Judaism, but simply a custom which has become accepted through consensus as defining a Muslim male). The spread of Roman-Christian culture in Europe had the same effect, Romanitas entailed the spread and adoption of customs and traditions which were not central to the civilizing aspect of literate Mediterranean culture.

CATEGORIZED UNDER: Culture

Bonus Kat

By Razib Khan | February 24, 2007 3:06 pm

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CATEGORIZED UNDER: Blog

Kat

By Razib Khan | February 23, 2007 10:32 am

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CATEGORIZED UNDER: Uncategorized

A request for bloggingheads.tv – Larison vs. Yglesias

By Razib Khan | February 21, 2007 12:21 pm

Most of you know I’m not very into politics…but I do have two political weblogs in my RSS which pound it hard, Matt Yglesias on the “Left” and Daniel Larison on the “Right.”1 I humbly request that Robert Wright have these two face off on Blogging Heads, just to see if English will allow them to communicate in any intelligible manner (please note, Ross Douthat over at The American Scene reads and is read by both, so there is only one degree of separation).
1 – Quotations are for two reasons…Matt Yglesias has sometimes stated that he wishes he lived in Europe…so he could be a European liberal (as opposed to Social Democrat). So his liberalism is really a function of the current political landscape. Larison is so reactionary that he really transcends being boxed in as “right-wing.”

CATEGORIZED UNDER: Blog

Sam Harris, God Intoxicated Man?

By Razib Khan | February 21, 2007 11:51 am

Sam Harris says:

I do not deny that there is something at the core of the religious experience that is worth understanding. I do not even deny that there is something there worthy of our devotion. But devotion to it does not entail false claims to knowledge, nor does it require that we indulge our cultural/familial/emotional biases in an unscientific way. The glass can get very clean-not sterile perhaps, not entirely without structure, not contingency-free, but cleaner than many people are ready to allow. One need not believe anything on insufficient evidence to experience the “ecstasies of Teresa” (or those of Rumi, for that matter). And those of us with the benefit of a 21st century education can be more parsimonious in drawing conclusions about the cosmos on the basis of such ecstasy. Indeed, I think we must be, lest our attachment to the language of our ancestors keep their ignorance alive in our own time.

Harris has been criticized by some secularists for his less than skeptical and critical attitude toward Eastern mysticism and supernaturalism which does not owe its existence to the followers of the One True God. But the reality is that I do not believe that Harris is an atheist in the way I am. I am a “cold atheist,” dead to the touch of religion or its attractions. I am not engaged in the world of humanity in the same way, and I do not exhibit the passion for my fellow man that Harris does, for if there is one thing that we know of him it is that he cares. And I believe his caring has driven him to a deep detestation of the myth of God, the father who has fled from our universe and gives us no succor but promises which remain unfulfilled. Evangelical Christians often say that their aggression in preaching their “Good News” is from love and altruism intent, would you not give a drowning man a helping hand and pull him up so that he could grasp at the glory of everlasting life? On a deep psychological level Sam Harris is, I believe, no different, he sees humanity drowning in false belief and he must witness. But do not confuse this for a coldness to religion and God, it is hot rage which motivates him, and Harris’ openness to Eastern mysticism suggest that he still seeks a way to save humanity from the drowning oblivion of materialistic naturalism.

CATEGORIZED UNDER: Religion

Things that make you go hm….

By Razib Khan | February 20, 2007 11:04 am

Bora sayeth:

Are you sure? How can a hierarchical, Chain-of-Being, authoritarian, sexist, racist, homophobic, xenophobic, religious ideology be ‘normal’ when it does not understand the world correctly? Isn’t it maladaptive to hold erroneous views of nature (and human nature) and try to organize societies to fit that view instead of trying to organize societies in synch with our best understanding of the way the world really works?

(mild typos fixed)
There’s so much I could say, and yet I will leave it without a word….

CATEGORIZED UNDER: Blog

South Park mega-site

By Razib Khan | February 19, 2007 11:36 am

For those of you who don’t know, check out Allabout-SP.net/, which has an archive of all the South Park episodes. I don’t own a TV mostly because most of the stuff is crap but still compulsively addictive…but the great thing about South Park is that I enjoy 80-90% of the episodes, so there is a good chance that I won’t waste my time.

CATEGORIZED UNDER: Blog

Etruscan update – more evidence

By Razib Khan | February 17, 2007 3:13 pm

etn.jpgSuccess begets succes, Dienekes was looking closely at genetic data due to the publication two papers which suggest an Anatolian origin for Etruscans (there has been previous mtDNA going back at least 5 years as well). He finds that central Italy exhibits a relatively high frequency of a variant of Haplogroup J, famously connected to the spread of farmers from Anatolia into Europe during the Neolithic revolution. Not that we’re on the trail of the definitive answer I suspect that things will “fit into place” far more easily. Scholarship is informed by scholarship, knowing that the Etruscans are of Anatolian origin, at least partially (remember that the presence of mtDNA suggests that they brought some of their women folk over) a massive movement.

CATEGORIZED UNDER: Genetics

Poll the experts!

By Razib Khan | February 17, 2007 12:32 pm

Do you remember the age before polling in politics? I don’t. Today we bemoan the emphasis on polls and idealize the past, before candidates knew in scientific and statistically significant detail the temperature of the democratic water. But no one is going to ban polls in the near future, for every person who complains about survey data there are hundreds who are clicking refresh over & over to find the most recent tracking results on their website of choice.
I think something similar is necessary for the sciences (or scholarship in general). Is George Lakoff a laughing stock (as Chris would have us believe), or a thinker of gigantic Aristotelian proportions? I suppose if you were a cognitive scientist you’d know, your sample of individuals in the field with whom you’d engaged in personal communication would be vast and you could get a sense of the direction that the wind was blowing. But for someone outside the field you basically have to trust someone on the inside and hope they aren’t misleading you (or, themselves). Is multi-level selection the next big thing in evolutionary biology, as Bora claims, or is it a relatively marginal and muddled field, my own general perception? Bora has made the Kuhnian claim that multi-level selection’s day will come when the older scientists die off, but how do we know that his perception is correct? One’s own sample is obviously going to be biased toward those with whom one is on common ground with, perhaps there are enormous social science departments steeped in conceptual metaphor theory that Chris as no knowledge of because he is boxed within his old fashioned world of symbolicists?
I think my point is pretty clear here: in the sciences quite often lay persons are in the position where they know with great confidence that a theory is absolutey accepted at its level of precision (e.g., Newtonian Mechanics) or totally rejected (e.g., the Aether theories). It is as if our knowledge of allele frequencies was certain with any degree of confidence only if they were operationally fixed (i.e., greater than 99%) or very rare or non-existent (i.e., less than 1%). Not only would my proposal help the public, I think it could give scientists some perspective about their position within their discipline.

CATEGORIZED UNDER: Culture

Agnostics smarter than Atheists?

By Razib Khan | February 16, 2007 12:11 pm

The always fascinating Ron Gunhame parses the GSS and religion & intelligence data. He finds:
Mean vocabulary score – Whites
6.52 Doesn’t believe
7.24 No way to find out
6.96 Some higher power
6.02 Believes sometimes
6.42 Believes but doubts
6.05 Knows God exists
Ron concludes that atheists are less intelligent than agnostics from this, but Jason Malloy in the comments has several follow ups which clear up the issue a bit and suggest that Ron spoke too soon.

CATEGORIZED UNDER: Religion

Kat

By Razib Khan | February 16, 2007 12:08 pm

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CATEGORIZED UNDER: Blog

Case closed, Etruscans are Lydian

By Razib Khan | February 15, 2007 11:09 am

etruscanagain.jpgYesterday I posted about the mtDNA results which suggest that Etruscans were Anatolian emigres to Italy. More data just <a href="came to light:

In the region corresponding to ancient Etruria (Tuscany, Central Italy), several Bos taurus breeds have been reared since historical times. These breeds have a strikingly high level of mtDNA variation, which is found neither in the rest of Italy nor in Europe. The Tuscan bovines are genetically closer to Near Eastern than to European gene pools and this Eastern genetic signature is paralleled in modern human populations from Tuscany, which are genetically close to Anatolian and Middle Eastern ones.

This mystery is over, so those few pages in the books on the Etruscans should be rewritten. Not only do the female ancestors look Near East genetically, so do the cattle in Tuscany! Additionally, ancient writers point to an Anatolian connection, this without the scholarly sophistication that we have at our disposal (i.e., they obviously weren’t engaging in deep philological or anthropological analysis, but transmitting folk memory).
Like via Dienekes.

CATEGORIZED UNDER: Genetics

Etruscan historical genetics done right

By Razib Khan | February 14, 2007 11:46 am

etruria.jpgMost of you know that I believe there are serious problems with much of contemporary historical population genetics. Grand unfounded narratives, and scientists who lack requisite historical knowledge, litter the field. But, narrow, precise and crystal clear studies do emerge now and then. This is a case in point, Mitochondrial DNA Variation of Modern Tuscans Supports the Near Eastern Origin of Etruscans:

Interpopulation comparisons reveal that the modern population of Murlo, a small town of Etruscan origin, is characterized by an unusually high frequency (17.5%) of Near Eastern mtDNA haplogroups. Each of these haplogroups is represented by different haplotypes, thus dismissing the possibility that the genetic allocation of the Murlo people is due to drift. Other Tuscan populations do not show the same striking feature; however, overall, ∼5% of mtDNA haplotypes in Tuscany are shared exclusively between Tuscans and Near Easterners and occupy terminal positions in the phylogeny. These findings support a direct and rather recent genetic input from the Near East….

Sometimes history can be extremely well illuminated by simple genetic studies. This is one such case. The origins of the Etruscans are (were?) “mysterious.” Some would hold that they are indigenous to the Italian peninsula, while others promote a more exotic provenance. Here is Herodotus, the father of lies:

The customs of the Lydians are like those of the Greeks, except that they make prostitutes of their female children. They were the first men whom we know who coined and used gold and silver currency; and they were the first to sell by retail. And, according to what they themselves say, the games now in use among them and the Greeks were invented by the Lydians: these, they say, were invented among them at the time when they colonized Tyrrhenia….

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CATEGORIZED UNDER: Genetics

SNPs, copy numbers & gene expression

By Razib Khan | February 13, 2007 12:04 pm

Had to link to a paper with such a title. Relative Impact of Nucleotide and Copy Number Variation on Gene Expression Phenotypes:

…SNPs and CNVs captured 83.6% and 17.7% of the total detected genetic variation in gene expression, respectively, but the signals from the two types of variation had little overlap….

Here’s a quote from a popular press article:

“We’ve been able to look back into our history and find changes that are older and likely to be shared among populations,” explained Dr Manolis Dermitzakis, senior author and Project Leader at the Wellcome Trust Sanger Institute. “But we also find many that are newer and less widespread.”
These are part of our recent evolution and a step along the way to understanding the origin and personal consequences of genetic change, not least for our wellbeing. This is a first generation map of biologically important DNA sequence variation”

CATEGORIZED UNDER: Genetics

A response to Mooney & Sokal

By Razib Khan | February 13, 2007 10:15 am

My coblogger @ GNXP Ikwa has a measured response to Chris Mooney and Alan Soka’s notable op-ed about the conflict between the Right & science. Here’s the gist:

For example, I don’t think it’s obvious that fundamentalist Christian fears that Darwinism will lead to the death of morality and the collapse of civil society are less reasonable or strongly-believed than the fear that the discovery of a genetic or biological contribution to social inequalities will lead to death of empathy for the disadvantaged and the collapse of all progressive values. Parenthetically, I don’t think either inference is warranted as I actually believe both antecedents to be true without finding myself compelled to endorse either consequent.

CATEGORIZED UNDER: Politics

Bouncing here and there and everywhere….

By Razib Khan | February 13, 2007 3:17 am
CATEGORIZED UNDER: Blog

Darwinian reflection

By Razib Khan | February 12, 2007 12:38 pm

When I was in 7th grade a school psychologist tested & interviewed me for the gifted program. During the knowledge section he asked me to describe Charles Darwin’s theory of evolution. I am pretty sure that my response was rather garbled, I don’t personally think I really understood evolution until late in 2003, nevertheless, after repeating the standard mantra of change over time generated by the process of survival of the fittest the psychologist paused and smiled at me. He stated that “That’s the first time ever that any student has responded to that question in a coherent manner.” I was aghast and confused. Granted, this was western Pennsylvania deep in Amish country, but at this point I didn’t even know that Creationists existed!

CATEGORIZED UNDER: Evolution
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