Friday, August 23, 2013

Well, if Ki Can Explain the Unbendable Arm, Why Not the Power of Jesus Christ?

After writing the last post, I found this ... rather "interesting" reasoning about the power behind the unbendable arm: "the power of Jesus Christ."

And there is just as much evidence to say that it is the power of Jesus Christ that causes the unbendable arm as there is evidence to say that it's ki energy: none.

Heck, there's as much evidence to say that it's the Flying Spaghetti Monster's noodly appendage that is causing the unbendable arm (which is just ironic on so many levels).

No, Ki Energy Does Not Explain the Unbendable Arm (Not even when the assertion is published in an academic journal)

A few years ago, I saw a link to an article titled, "The Physiological Study of Ki in Ki Aikido (2)" (PSoKiKA2) published in the Journal of International Society of Life Information Science in 2001. As a person who used to practice aikido (a lot) and who still dabbles in it from time to time, the concept of Ki and the practice of Ki Aikido were familiar to me.

And I've long felt they they were bunk.

What is ki?
Okay, so I've revealed my position right away, but the evidence for the physical existence of ki is paltry at best; along the lines of evidence for ghosts, bigfoot, and the yeti. Indeed, the idea of ki is an embedded concept in Japanese culture, and it is used in forming many words (denki: electricity, kibun: mood, tenki: weather, and aikido: literally "harmonious-spirit way"), and it also has a spiritual/religious meaning. A good analogue of ki is the word (and concept of) pneuma, which has the double meaning of "breath" and "spirit/soul": it has both a physical and a mystical meaning. Indeed, like pneuma, ki is often associated in its physical manifestation as breath, especially in the spiritualistic extremes of Aikido practice. It also has a history of deep associations with Far-Eastern religions (much like pneuma had a history of deep mystical and religious associations in Classical Greek society and - through the works of Aristotle and the Stoics - the pre-Enlightenment concept of medicine, too).

Assessment of PSoKiKA2
Anyway, back to "The Physiological Study of Ki in Ki Aikido (2)." The article is built on the whole notion that the ki in Ki Aikido is a quantifiable physical phenomenon, with the very first sentence in the introduction unequivocally stating:
Aikido is a Japanese martial art, in which Ki is very important and is not always a physical power. (1,2)
Yes. There are references.  In fact, the article cites a total of three references, each one of them about Ki Aikido. In this case, references 1 and 2 are books in the popular press about Ki Aikido (Ki Energy for Everybody and Ki in Daily Life). The final reference is actually the complement to this study (or "PSoKiKA1"), which was published in the March issue of the same journal.

The methodology seems to be okay, but remember that the whole article is resting on the (untested) axiomatic premise that ki is real and can be measured. The introduction continues, though, thusly:
To identify what Ki is in Aikido, we studied what physiological state is controlled when the unbendable arm is performed. The experiments to study the state of the unbendable arm consist of three different conditions: (1) the state of the arm being unbendable by applying only physical power, (2) the state of the arm being unbendable by being powerless without resistance, and (3) the state of the arm being unbendable by extending Ki. Through analysis of the differences among the three states examined, the difference between physical power and Ki should be understood.
Um... Yeah. A little explanation is needed here, I think. First, what is "the unbendable arm"? Here is a quick video explanation (with a bunch of mumbo-jumbo, but not that much of it) that also shows the three conditions of the experiment (the guy in the video calls state (2) "floppy arms"):

In short, when you do the unbendable arm, your arm cannot be (easily) bent by your partner, even if they are trying really hard to bend your arm (which is why it's called "unbendable arm"), and it's a concept that exists in other martial arts, too. All the stuff about the poses is hooey, and you definitely can do it as a party trick to impress people. (But it rarely does impress people, unless you use it to show a person doing pull-ups on your arm.)

Going back to the PSoKiKA2, the researchers hooked up a Ki Aikido master a bunch of apparatuses to see what physiological effects and brain activity there are when the master is (1) actively using muscular strength to resist someone trying to bend his arm, (2) using nothing to resist the person bending his arm, and (3) using the unbendable arm technique to resist someone trying to best his arm.

Not really a bad set-up, except for the premise that what makes the unbendable arm function is ki. *sigh*

Still, PSoKiKA2 gets what looks like decent data and shows that the physiology and brain wave activity is different between condition (1) and condition (3). (Side note: condition (2) is treated as if it were a refractory period between the two tested conditions, and ought to be no different than the baseline condition that was measured prior to condition (1)). Specifically, the results showed:
  • Relative to condition (2), the heart rate was elevated under condition (1) but not condition (3).
  • There was more blood flow at the neck under condition (1) than condition (2).
  • Both condition (1) and condition (3) showed almost instant blood pressure increase, but it was higher for condition (3).
  • GSR increased sharply under condition (1) but not condition (3).
  • Abdominal respiration ceased under condition (1) but was continued under condition (3).
  • Neck temperature decreased under condition (1) but increased under condition (3).
  • Condition (1) showed both alpha and beta wave brain activity, but condition (3) showed only alpha wave brain activity and no beta wave brain activity compared to condition (2).
Now, I would look at these results, and I would say that this conclusively shows that this Ki Aikido master is doing something very different between condition (1) and condition (3). In fact, that's all that PSoKiKA2 can show. If I had data from other subjects (like other aikido masters or complete off-the-street novices who were taught the basics of the unbendable arm mere seconds before testing), then I would be more comfortable to say that condition (1) and condition (3) are not merely artifacts created by the practitioner. (As an aikido practitioner, though, I would say that they aren't, but the data of one individual do not support my personal experiential - and therefore potentially subjective - observation.)

However, this isn't what PSoKiKA2 concludes. Indeed, here's what the authors thought the results meant:
... when resisting with Ki, the subject kept breathing and the exhalation dominated when starting to resist the power, this is presumably the factor functioning to resist the power applied.

... Coordinative function of the frontal lobe of the left-brain with the region for vision in the right brain was observed. The force through Ki might generate this connection.
Yeah, mumbo-jumbo that is also self-confirmatory. Ki and breath are always connected, as is ki and the mind. Finding these things is not proof of ki, but is either an explanation of acculturation or associative physiological processes. For example, in Aikido, we are taught a form of demonstrating the unbendable arm in which we don't breathe when physically resisting. See what the instructor does from 1:00? He purses his lips when not talking; when watching a similar demonstration in other dojos, this is often done unspeaking and with a clenched position. To one extent, it's play-acting. To another extent, it is true that if we are actively resisting, it's difficult to breathe easily, but for the purposes of demonstrating the unbendable arm, it's not so difficult as to cause you to cease all breathing. (Here, the Aikido master in the study either consciously or unconsciously play-acting the role assumed in the active resistance portion of the demonstration.)

So what do I think causes the unbendable arm, if it isn't ki? Well, I think that it's two things: mechanical advantage in work and physiology.

Mechanical advantage in work (aka the dot product of orthogonal vectors)
Waaay back in undergraduate (or maybe high school), when we took physics, one of the things that we learned as a part of kinematics was the concept of the dot product. Now, dot products are important in kinematics, since forces can be represented as vectors, and vectors can be manipulated using that specialized area of algebra called linear algebra.

One of the more important lessons that we learned in basic physics (the one that tries to teach kinematics without relying on the students' knowledge of linear algebra) is that the dot product of orthogonal vectors is always equal to zero. In other words, the net work done by perpendicular forces is nothing. Nada. Zilch. Zeeero. (And - conversely - the net work done by parallel forces is always equal to one or negative one, depending on directions of the vectors.)

Why is this important?

Well, the unbendable arm is actually - on one level - about the application of forces. The one trying to bend the arm (the "partner") is actively exerting force on the arm of the one resisting the arm-bending forces (the "practitioner"). In order to not have his arm bent, the practitioner must be exerting a force, because of the Law of the Conservation of Energy.

When the practitioner is actively resisting by pressing back on the partner's force, they are effectively creating a force vector that is parallel to the partner's force vector. In practical terms, this means that the maximum potential force can be imparted in the task, and the person exerting more force will be able to bend the arm in the direction they want. Since the partner has better leverage (and is usually using two arms), the partner is almost always able to overcome practitioner's ability to exert the force necessary to keep his arm extended.

However, when in the unbendable arm, the practitioner actually exerts force perpendicular to the forces exerted by his partner. Watch the video again, especially from 1:30. The force that the instructor is exerting is actually in the direction in which his fingertips are pointing: roughly perpendicular to his partner's hand positions. Since the angle between the forces approaches 90 degrees, the total amount of force that can be exerted by the partner on the practitioner approaches zero, which makes it very easy for the practitioner to utilize muscle force to counteract the remaining force exerted by the partner.

This isn't only the case when you have a partner using their hands and arms to try and bend the practitioner's arm. It also works with simple weights strapped across the arm at the inside elbow (provided the practitioner can stabilize his wrist and hand on something). So long as the practitioner extends a forward force, the weights will not bend his arm. It still takes work, though, since the force vectors are not at precisely 90 degrees, nor is there any feedback that the practitioner can receive from the weights, which is why it's actually harder (at least in my experience) to do unbendable arm with dead weights. But this leads to the next factor: physiology.

Physiology (specifically the stretch reflex response)
The actions of the human body are not purely the realm of abstract kinematics. The forces it creates are derived from the musculature. No surprise there. However, human skeletal muscle has a stretch reflex response, and:
When a muscle lengthens, the muscle spindle is stretched and its nerve activity increases. This increases alpha motor neuron activity, causing the muscle fibers to contract and thus resist the stretching. A secondary set of neurons also causes the opposing muscle to relax. The reflex functions to maintain the muscle at a constant length.

Gamma motoneurons regulate how sensitive the stretch reflex is by tightening or relaxing the fibers within the spindle. There are several theories as to what may trigger gamma motoneurons to increase the reflex's sensitivity. For example, gamma co-activation might keep the spindles taut when a muscle is contracted, preserving their stretch-sensitivity even as the muscle fibers become shorter. Otherwise the spindles would become slack and the reflex would cease to function.
In short, skeletal muscle has a way of maintaining a certain level of stretch in them that helps maintain the lengthened arm position by creating fine-level manipulations within the muscle fibers to ensure that the overall tension of the musculature is maintained unconsciously. This is important when describing the difference between doing the unbendable arm with a partner and with weights.

When practicing with a partner, the stretch reflex response continuously recruits different muscle fibers to optimize maintaining the position of the arm in its outstretched position. As the partner shifts his leverage (even minutely), muscle fibers in the practitioner's arm are automatically recruited and relaxed, which means that the practitioner isn't consistently using the same muscle fibers to continue keeping the arm extended.

Conversely, when practicing with weights, there is no shifting. (At least, there shouldn't be.) The weights have a constant, unchanging downward force due to gravity, and (if the stabilization point is a fixed surface) the stabilization point is also exerting a constant, unchanging upward force on the back of the hand. The stretch reflex response is to continue to keep the exact same muscle fibers recruited and leave others unrecruited. This means that the arm quickly tires (unless the practitioner moves his position or unless the practitioner uses the partner's shoulder as a stabilization point, or both).

Indeed, we would encounter this type of problem were we to simply keep an arm raised at shoulder height. We might start off by keeping the arm perfectly still, but our shoulder would quickly start to fatigue, and we would be sorely tempted to either drop the arm or move it to a different position. Even rotating the arm or changing the angle of the shoulder or bending the arm at the elbow will suddenly make the task feel easier (at least for a time). This is because the stretch reflex response recruits different unfatigued muscle fibers and releases fatigued ones in order to maintain the new position.

Closing Remarks
I don't know for certain that the unbendable arm is actually caused by the realization of the dot product of forces combined with the stretch reflex response in the arm, but these two things actually have an internal logic and consistency to them that ki doesn't have. If we believe that it was actually ki energy that kept the arm straight, that would mean that the practitioner can convert the partner's physical energy into ki energy. It also means that the process of such energy conversion just happens to look like it takes advantage of the dot product of orthogonal vectors on the physics side and the stretch reflex response on the physiological side.

In short, one doesn't need to rely on mumbo-jumbo non-explanations like, "it must be associated with ki," unless you happen to be using the concept of ki purely in its ineffable sense. However, to write a physiology paper that effectively says that we can measure and observe ki in the body's response to a set-piece in Aikido circles is akin to citing the "power of intercessionary prayer" in healing the cataracts in Sam's mum:

... and the evidence about the studies of the efficacy of the power of intercessionary prayer is that the studies are heavily biased with internal assumptions that cannot be tested, are - at best - serendipitously aligned with the outcomes that the experimenters expect to see, and so riddled with confirmation bias that negative or null outcomes are often explained away or not even included as "valid" results.

Take home messages:

  1. The PSoKiKA2 study does nothing to actually show the existence of ki.
  2. The unbendable arm can be explained through simple kinematics and physiology.
  3. Heavily biasing your scientific research with predetermined causative effects means that you will certainly draw the wrong conclusions from your science (even if your method of obtaining the data was decent or even good).

Tuesday, August 20, 2013

Why BMI is not accurate for taller populations

Lisa Wade (at SocImages) links to a really good, publicly accessible run-down on the various environmental reasons why human (and animal) populations have been growing heavier. The author makes a pretty quick equivalence between obesity and BMI by (effectively) just equating the two, thusly:
And so we appear to have a public consensus that excess body weight (defined as a Body Mass Index of 25 or above) and obesity (BMI of 30 or above) are consequences of individual choice.
Now, I believe that there are two germane debates when it comes to the issue of BMI, obesity, and health: (1) the validity of applying a population metric to individuals (which I contend is categorically, logically, and methodologically incorrect) and (2) the question of whether BMI is actually a useful metric of our population. I would contend that the author focuses mainly on studies that presume that #2 is true, which then allows him to focus on answering #1. (I will admit that it's far more juicy and fun to look into #1, but is epistemologically lazy.)

Before continuing, let me first state that we cannot disagree with the fact that the average weight-to-height ratio (otherwise known as the BMI) has been increasing over time. This is a fact. It has countless reams of documentation that support it. Arguing that it hasn't happened is akin to shouting imprecations of denial against the existence of the sun while standing in the middle of a desert at high noon. In short, the numbers are irrefutable: the BMI ratio is increasing. Indeed, the article agrees that this is happening, and does an excellent job of examining the potential causes of the increase in BMI. But what the article misses is the very question of whether BMI itself (and therefore the mechanical definition of "obesity is when BMI>30" that no doubt underlie most of the studies in this area) is actually a useful metric to use on our current population.

The reason why I bring this up (almost once each year on my blog) is that many people breeze past the fundamental question of whether BMI actually is doing the job we assume it is (supposed) to be doing, which is (at the very least) providing a description of the relative height-to-weight ratio of the study population. Indeed, to the issue of the misapplication of the BMI, I will only repeat my position that it's categorically, logically, and methodologically incorrect. (I'll let Devlin explain why.) Instead, below, I'm going to point out one fundamental flaw in the BMI itself: height.

Taller people have a bigger BMI than shorter people of the same build. This is an important (but unsurprising) statement. Also important (but also unsurprising) is that a person can gain weight (or lose weight) without gaining (or losing) height. All this means that height is the independent variable in the description of BMI.

Furthermore, looking at the formula for BMI (weight/[height^2]) it's easy to note that increases in height (say 6 inches/~15 cm) will have a far greater impact to the BMI than an increase in weight (say 6 lbs/~2.5 kg), since height is squared, while weight is not. This means that - as the population gets taller - in order to remain below a BMI of 30, the population must weigh relatively less than a shorter population. Why? It's because the relationship of height-to-weight that forms the BMI was derived from data about 19th century Belgians (who were 5'5" tall, and for whom the formula of wt/[ht^2] was adequate).

But things have changed - a lot - in the height department.

Specifically, humans have become taller than those 5'5"-tall, mid-19th century Belgians. Unfortunately, though, the BMI calculation we use is still that same one derived over 150 years ago (which, btw, was not meant to be a measure of health). But what does this mean? It means that - as a population gets taller - it must become relatively lighter in weight (i.e., far thinner) in order to remain at the same BMI. For example, let's see what happens when we compare the two 2008 US presidential contenders: Barack Obama and John McCain:

Barack Obama: 6' 1.5", 180 lbs = 23.4 BMI
John McCain: 5' 7", 165 lbs = 25.8 BMI

True, Obama was (and remains) thinner than McCain, but - to show how much height influences the BMI calculation, compare, McCain to (then) outgoing president, George W. Bush: at 5' 11" and 190 lbs, George W. Bush had a 26.5 BMI, which is 0.7 higher than McCain's, but was (without much argument) thinner than McCain. So, if Bush was thinner than McCain, but had a higher BMI, and Obama has a slightly lower BMI than McCain, but is a LOT thinner, why is this the case?

The reason why the BMI fails at predicting taller populations is that BMI is fundamentally measuring the relationship incorrectly. For people who are around 5'5" tall (like those mid-19th century Belgians for whom the BMI was calculated originally), then the relationship is actually pretty good. However, with significantly taller (and significantly shorter) populations, the BMI falls apart, because - at these heights - the BMI is no longer acting as an accurate measure.

As Devlin (over at Devlin's Angle) writes:
The BMI was formulated, by a mathematician, not a medical physician, to provide a simple, easy-to-apply mathematical formula to give a broad, society-level measure of weight issues. It has absolutely no scientific or medical basis. It is based purely on a crude statistical analysis. It measures a general society trend, it does not predict.
I would put it one further: saying that "it measures a general society trend, based on the assumption that we can extrapolate from a statistical relationship found among mid-19th century Belgians; it does not predict."

And - in general - populations have been growing taller than mid-19th century Belgians. Especially in Asia. For an example of the change of Japanese average height over time, see here. And this means that these populations are moving away from that range of heights at which BMI was calculated, and for which - at the population level - BMI is/was relatively descriptive.

I'm not even going to get into a discussion about how screwed up BMI gets when you look at populations of athletes. (Hint: the US Olympic team is almost definitely in the "overweight" or "obese" categories, since most of them have a higher-than-average muscle density.)

My other entries on BMI (many of which were motivated from reading SocImages) are here

Monday, August 12, 2013

Peeved (again) with Sociological Images blog

I'm again disappointed by Sociological Images. In a recent entry - "Open Thread: Selling Push-up Bras with the Male Body", the author provides a commercial from Thailand that uses a male model to sell a bra. Apart from mentioning that it's from Asia (and even mistaking the origin of the commercial), the author make absolutely no attempt at even placing the ad in the cultural context of its most likely viewers. Instead, the author ends with:
I wonder what y’all think. Does this queer the body? Is there a transgressive identity behind the gaze? Or is it just more gimmicky advertising based on normative expectations? Both?


I would like to turn it around: "I wonder what you're thinking. Can we impose American gender politics and norms on a non-American audience who are embedded in their own cultural gender politics and norms? Is there a generalizable connection that you can draw between Thai and American gender politics (one that you're just not telling us about)? Or it this just another gimmicky and lazy post that makes absolutely no attempt at analyzing an Asian culture from anything other than an American perspective? Both?"

Seriously, if you're going to write a post in a sociology blog about things from Asian cultures (that are marketed to those domestic audiences) or things in the States that have had a massive influence from one or more Asian cultures (like what was posted by the same author on the same blog just the other day), then it makes sense to me that you should at least make an attempt at analyzing those things in something other than a White-American-only context. This inability to even start to analyze a non-American commercial from a non-American context is something that this author has done a lot (including - but not limited to - this, this, this, this, and this for Asian things in respective domestic contexts).

Is it too much to ask the person with the PhD in sociology to go the additional couple of yards and at least do what she did when writing about "Korean appropriation of American Indians":
It’s difficult (for me) to know how these stereotypes of native North Americans “work” in Korea. It appears to mean something to Koreans, otherwise why use the imagery and narratives, but what? And how should Americans who oppose the stereotyping (and erasing of modern) Native Americans talk about this “borrowing”?
I believe that it's okay to publicly admit when one doesn't know the culturally contextual significance of the imagery displayed, which is why I actually think that it was useful when the author wrote - in "Are they racist or are we ethnocentric?":
I don’t know if [the lack of a cultural connection between chicken and black people is] true [in Australia]. But if it is, it raises interesting questions as to (1) just how cognizant companies should have to be about various stereotypes around the world and (2) whether the biased histories of some countries must be more attended to than others.
Admitting the lack of cultural knowledge is actually useful, since it then gives the context for the author's two points.

It would be nice to see the author put in this minimum of due diligence, instead of (yet again) having the audience explain why the sociological context of the United States is not the appropriate one to use when viewing the presented thing(s). Of course, this is merely Sociological Images, and admittedly, the blog entry in question was an "open thread", but seriously, how much time and effort would it take to write something like, "There are many social contexts in Thailand that undoubtedly inform the messaging in this commercial. However, in a broader context - which can include the US - ..."

... or maybe all of this is merely implied when one is talking about the cultural contexts of countries and cultures of which one is unfamiliar. After all, it's what most people do when assessing the cultures of other countries. It's just sad that a person with a PhD in a field in which one ought to know better is doing it (apparently obliviously).

Friday, August 09, 2013

More Japanese Beatboxing

Last year, I posted some videos of Japanese Beatboxer, Hikakin. He's come out with some new stuff, and I saw this one recently:

Wednesday, August 07, 2013

Musings on Lactose Persistence

An interesting map of lactase persistence from Nature:

Differences in Gene Expression & Hybridization
An interesting things from the article:
Most people who retain the ability to digest milk can trace their ancestry to Europe, where the trait seems to be linked to a single nucleotide in which the DNA base cytosine changed to thymine in a genomic region not far from the lactase gene. There are other pockets of lactase persistence in West Africa (see Nature 444994996; 2006), the Middle East and south Asia that seem to be linked to separate mutations3

Since lactase persistence in West Africa, the Middle East and South Asia all seem to be linked to separate mutations, I wonder:

  1. if the different mutations for lactase persistence are differently efficient, and
  2. if people who have parents from different lactase hotspot regions have significantly different lactase production capability.
Since the mutations of lactase persistence occurred independently in these different populations, it means that it is possible that each population might have a different efficiency of producing lactase. (It's not necessarily true, but it is possible.) For example, if Northern European populations could digest x milliliters of cow milk in t seconds, would West African populations be able to digest the same quantity in the same amount of time? Would this hold for all quantities? For commonly drunk types of milk (e.g., cow milk, goat milk, sheep milk, mare's milk, camel milk, etc.)? And for all hotspot populations? These would be interesting things to check out (especially if you were a cereal company who wants to open new markets...)

With regard to the question of whether genetic hybrids would have better capacity of producing lactase, it is important to determine whether the trait is dominant or recessive. In a comparative study between the Northern European and the Middle Eastern mutations for lactase persistence, the authors assume that the genetics of both mutations are dominant traits, which would mean that only one gene is necessary for the trait to be expressed. If a person had both the Northern European mutation and the Middle Eastern mutation, therefore, it is likely that they could well express both lactase persistence mutations. (The assumption of dominance is also more likely, considering that upwards of 90% of the populations in the hotspots can digest lactase, which strongly implies that it's a dominant trait, since a recessive trait is unlikely to emerge at such a high rate, unless there were some strong selective pressures for that trait.)

The Mongol Question
In another note, the article is mum about Mongolia. Indeed, the shading of lactase persistence is at a pretty low resolution (as it is for much of Asia), but it estimates it at around ~45%. This strikes me as a little odd, since much of the population does consume mare's milk, and some regions also consume yak milk and others consume camel milk (i.e., in those regions where they herd yak and camels, respectively). From these milks, different products are made, which serve as a major food source throughout the year. Now, maybe ~55% of the Mongolian population is lactose intolerant, and just go around with the runs and bad gas all the time, but I couldn't find any information about Mongolia. Instead, when I looked for lactose tolerance data for Mongolia, I kept pulling up a 1984 study of ethnic populations in China, including Inner Mongolia. One note, though: Inner Mongolia has a very different demography than the nation of Mongolia, and it's not clear from the reviews of the study that the authors tested ethnic Mongols (who are a minority in Inner Mongolia), Han Chinese (who are the dominant majority), or other minorities (e.g., Manchus, Hui, Daur), or even if they determined the level of hybridization of the subjects (since determination of ethnicity is a social construction - in which a person who is half-Han could still be considered to be Mongol and other ethnic minorities are also considered to be Mongol - whereas lactase persistence is based on biology). I'm going to guess - based on only anecdotal evidence and inference - that the degree of lactose persistence in Mongolia is higher than that of Inner Mongolia and that it could well be higher than the ~45% indicated on the map.

Even though the resolution of the data is pretty sparse in Asia (apart from South Asia), it's interesting to note that if we assume that the darker band of lactose persistence in northern and eastern Asia are due to the Mongols (which I think is justifiable, based on the wealth of evidence that Mongols do consume significant amounts of milk products), then the dark spot of lactose persistence in Japan's main island is additionally interesting. If true, it would appear to bolster some minor lines of genetic evidence that link Japanese populations to Mongolia and potentially explain why lactose persistence is a far more common trait in Japan than it is in the nearby Korean peninsula.

In any event, it would be interesting (and somewhat fulfilling) to see more data from northern Asia (especially from the herding ethnic groups found in that vast - and under-sampled - area).

Of course, I'm not a geneticist, but when I see maps like these, they make me wonder about the interesting implications of genetics.