Category: Culture

Austin vs. Portland

Posted on by Razib Khan


The above video is from a Portlander who is quite anti-Austin, though in a tongue-in-cheek fashion.

The issue of cross-city comparisons was on my mind for two reasons. First, Joel Kotkin wrote an article last fall in Forbes, America’s Next Great Metropolis Is Taking Shape In Texas, that friends are sharing on Facebook. Second, I’m someone who has lived in both cities (around downtown Austin and the Hawthorne neighborhood in Southeast Portland). I still travel between Texas and Oregon, and it’s pretty interesting how people react when they find out that I live in Texas or that I’m from Oregon in the other locale. Kind of a wary curiosity about my opinions (in Austin one is careful to mention one’s California days lest the wrath of the native be triggered).

In Oregon it rains gently at an angle; raincoat, not umbrella.

First thing, though the video above is kind of silly and not too serious, I do want to address one thing. Texas is not more arid than Oregon. I’m actually originally from eastern Oregon, so I have to remind people that 2/3 of the state is quite dry, whether it be semi-arid or arid. Inspection of the above map shows that a much larger portion of Oregon is extremely arid than Texas. Also, Portland gets 41 inches per year. Austin? 37. The difference is that Portland’s is frontal precipitation that is dispersed over much of the year in drizzles and overcast skies, while Austin is subject to more convective bursts. Where there are 145 sunny days in Portland per year (remember there is summer drought), there are 230 such days in Austin.

Austin combines a vertical downtown with huge expanses of quasi-suburban sprawl.

Austin still has a lower cost of living, mostly because of housing. Due to its rapid population growth, Austin’s transportation infrastructure and supply of health professionals is far inferior to Portland. But, the population growth is obviously due to an economic dynamism which Portland can’t match; unless you work at Intel it seems most educated young people in Portland are retired and working as a barista on the side (this is an exaggeration, but you get the point).

Can you name Portland’s iconic food?

I’d say Austin’s food is definitely better and cheaper. For beer, I will give the nod to Portland, which has a more well developed scene for microbrews. The same with coffee. It’s hard to compare outdoor amenities. The Pacific Northwest has real trees. The rest of the country has bushes. Austin is near the Texas hill country, but Oregon has hills, mountains, and gorges. It has Crater Lake. But because of the warm weather you can go swimming and enjoy the outdoors the whole year without much

Vistas

preparation in Austin. The Colorado river in Austin is less geologically impressive than the Willamette, but there’s a lot more recreational activity because it’s warm and dry so much of the year.

A major difference between Portland and Austin is the university scene (or lack thereof). Portland State University has about half the student body of UT Austin, but its prominence within the city (and nationally) is far less than that simple quantitative measure. UT is located right north of downtown, so it’s an integral part of the Austin scene. In contrast, though PSU is located just south of downtown Portland, it is a much lower key presence. UT Austin is the flagship campus of the state university system of Texas. In contrast, PSU did not initially offer doctoral programs, and is a Research 2, a opposed to a Research 1, institution. Its roots were as a commuter school, and it still has many non-traditional students. In contrast UT Austin students are some of the most academically talented kids from all over Texas, which does not have large elite private universities, like California (Stanford and USC are both much larger than Rice).

Oregon has good beer

Finally, the arts & entertainment scene. This is really about taste obviously. Portland has a more artisanal arts scene, if that makes sense. More off the wall, homegrown, and organically and haphazardly presented. I didn’t really take advantage of it much when I lived in Portland, but honestly I’m not big into the arts scene here in Austin. But I’ve gone to shows now and then. It’s hard not to in Austin, which is crawling with musicians, and where live music is blasting up and down 6th street. But as Austin has gotten more popular and well known, it has also gotten more commercial and commoditized. National acts like Taylor Swift an Adele swing through town, and SxSW and ACL are huge draws. It’s easy to take it for granted, and honestly now it’s just part of the background furniture of my life.

Ritz beats the Baghdad

Note: I don’t have much to say about the fact that Austin is the capital of Texas. For me the main consequence of this fact is that perhaps this is one of the major reasons that the flagship university of the state system was located here (though usually it doesn’t work out like that). The Capitol is downtown, and there’s some political stuff going on there. But it’s pretty sealed off from the rest of the town. In contrast, Sacramento, probably is more affected by being the capital of California, since the city is less distinctive. And Albany is totally overshadowed by being the capital (I am naming three cities where I have actually lived at some point).

Treasure your exceptions, progress is real but not universal

Posted on by Razib Khan

The beginning of How the Scots Invented the Modern World describes the execution of a man for the crime of atheism around 1700 in Scotland. More precisely, this individual was rather loud about their heresy, and that is always the problem. Silent dissent is usually tolerated. This is the last time someone was executed for this particular crime in the British Isles.

In the United Kingdom the book was more accurately titled The Scottish Enlightenment. A relatively moderate and low fuss affair, the Scottish Enlightenment gave us Adam Smith and David Hume, to name two. The point of the book is that in it one can see many of the seeds of the liberal Enlightenment in Scotland, which at the beginning of the 18th century was arguably more backward and medieval than its southern neighbor.

But the “modern world” means many different things. Mobile phone technology is ubiquitous, to the point that even the poor in developing nations have it. But a broader consumer affluence is out of reach for many. And the rights and liberties of a liberal democratic order are more an ideal than concrete existence for much of the world’s population (and you have cases such as Saudi Arabia where illiberal norms and politics merge with consumer affluence).

As you may know a young man was killed by his fellow students in Pakistan for the crime of blasphemy a few days ago. Whether he was an atheist or a free thinker, or a skeptic more generally, can be hard to ascertain. But the critical aspect is that he was killed in broad daylight by a mob. He was lynched. This being 2017, you can watch a video of the killing, and hear his screams as he is murdered in front of a crowd.

One aspect people have been noticing is that this was a killing enabled by majority and consensus opinion. Abdul Wali Khan University Mardan is a public university, not a cloistered madrassa or a branch of the Red Mosque network. You can’t blame ISIS or some crazy jihadi network. These were university students.

Pakistan has a population of 182 million. The United States around 300 million. I understand that Americans believe we are the future. That the rest of the world is the exception. But how long will that be? Perhaps the arrow of history is more a circle?

Modernity is not magic with Muslims

Posted on by Razib Khan

There are many reasons I have become very skeptical of the media over the years. Though I do not subscribe to the conspiracy theory paradigms, it is obvious that the mainstream media often combines fidelity to precise narratives with a lack of detailed knowledge about the topics they are covering. In other words, they’re stenographers with an agenda. When you don’t know the topic they are expositing upon they can seem quite persuasive. But when you do know the topic they are addressing the emperor can be revealed to be naked. Naturally this warrants concern in most people who observe this, as if they are catching errors in the matrix.*

One area that this problem crops often for me is in regards to media coverage of Islam and and the Middle East. Most reporters don’t seem to really know much about their beat in a deep sense, so they are superficially taking in facts and putting them through coarse interpretative filters.

To name names, David Kirkpatrick covers the Middle East for The New York Times. I read his stuff, and he is not a bad journalist, but he clearly has no deep familiarity with the history of the Middle East or the details of Islam. His work is like a pop-tart; sweet, temporarily filling, but long on a sugar-rush and short on filling substance. For example, he can talk about a contrast between peaceful Sufis and Islamist militants Libya, without knowing that Sufi orders were often militant organizations, and that Libyan independence after World War II was spearheaded by a militant Sufi order. (I know this, so I’m passing this on to you!)

But readers of The New York Times “know” that Sufis are peaceful. So for prose contrast it makes sense that Kirkpatrick would bring that up. Never mind that this is so reductive to be useless in terms of getting people a better picture of reality.

In the interests of adding context, let me add something to the story about FGM in Michigan which is prominent in the news today. A Dr. Jumana Nagarwala is accused of practicing FGM on young girls. Though it is not emphasized in the American media (because it wouldn’t mean much), it seems she is from the Dawoodi Bohra of Ismailis. In India the Bohra community is well known, as it is a very distinct group from the majority of Muslims, who are Sunni, and even most Shia. Its origins seem to be among the mercantile castes of the Gujarat coast, who were converted to a particular Ismaili sect of Shia Islam.

I have some “book learning” about this sect under my belt because I read Mullahs on the Mainframe: Islam and Modernity among the Daudi Bohras about 15 years ago on the recommendation of my friend Aziz Poonawalla, who is a member of this community. Mullahs on the Mainframe was topical in the post-9/11 era because it seemed to depict a community which was both modern and religiously orthodox and observant, with fewer tensions being a minority in the West than other groups of Muslims. I don’t want to rehash that line of argument too much; descriptively it is correct that Daudi Bohras are a well behaved minority who attain success, combined with adherence to traditional beliefs and practices (Daudi Bohras, like many conservative Islamists, tend to “look” obviously Muslim because of matters of grooming and dress).

But another aspect of the Daudi Bohra community is that it is one of the few in South Asia that practices FGM. I don’t know or care about the prevalence, extent, or origin of the practice among the Bohra. When I saw the doctor’s name, which seemed South Asian, I immediately suspected she was from the community (the type of headscarf seemed familiar too).

The point of this post is not to demonize the Daudi Bohra community; the vast majority of the world’s Muslims who engage in FGM are not Daudi Bohra. The Shafi school of Sunni Islamic jurisprudence is the big offender in terms of numbers. Indonesian Sunnis are Shafi, so that nation often praised for its tolerant version of Islam has a very high proportion of FGM. Rather, it is to point out that the neat narrative frameworks we prefer are often not descriptively correct nor predictively useful. Since 9/11 rather than a more complex and nuanced view of Islam it seems that opinion leaders have been converging upon the idea that the religion is either with the angels or the devils, rather than a man-made thing which occupies the area in the middle.

The reliance on theories and heuristics which appeal to our sensibilities as right and true misleads in many ways. The arc of history bends toward justice, but the path is winding. The Protestant Reformation was rooted in the more literate and well off classes, and aimed to rid corruption from the Christian church. In the process it unleashed horrible intolerance, cultural genocide, and conflicts which resulted in tens of millions of deaths. Not taking a view on the Reformation as a whole, it is clear that its consequences are not so simply integrated into the Whig version of history when taken in full.

Ultimately we need to rush less quickly toward our preferred conclusions, which align neatly with our prior models. Rather, we need to explore the sideways and what we think are certainly dead-ends, because sometimes those dead-ends will open up startling new landscapes (by the way, I think the “rationalist” community is much better at this than the general thinking public, though that’s not saying much).

* When I was in grad school an acquaintance mentioned this in relation to Jonah Lehrer before his exposure. Lehrer was persuasive whenever he was talking about a topic he wasn’t familiar with, but was clearly out of his depth whenever it approached something he was familiar with.

$150,000 only gets you so far….

Posted on by Razib Khan

The above salary range seems accurate. I know newly minted PhDs in computer science may “only” get in the low $100,000 range at Google. So a salary in the mid six-figure range is totally reasonable with a few years of experience.
Recently a friend who is an engineer at Google in Mountain View got a transfer to Boulder, where they bought a house. He’d been trying to buy in Mountain View for a while…but that just wasn’t happening. Boulder isn’t cheap, with 178% the national average in cost of living. But it’s nothing compared to Mountain View, where the average housing cost is 7.5 times the national average.

What’s striking to me is the high variation in cost of living in American urban areas:

Overall cost of living
San Francisco 272
New York City 180
Seattle 177
Boston 170
Los Angeles 166
San Diego 166
Portland 140
Denver 128
Miami 123
Austin 117
Chicago 111
Minneapolis 109
Houston 102
Atlanta 102
Raleigh 102
Philadelphia 100
Phoenix 99
New Orleans 96
Dallas 95
Baltimore 90
Pittsburgh 88
Cincinnati 86
St. Louis 85
Des Moines 83
Memphis 74
Detroit 73

Coffee is not measured by its price

Posted on by Razib Khan

An interesting piece on a $1 coffee joint, Has Coffee Gotten Too Fancy?:

Mr. Konecny’s ambitions for Yes Plz go beyond selling a high-quality cup of coffee at that magic price point, though he knows that it sends a powerful message. What he wants to do is shift the very nature of coffee culture. He has no patience for what he calls the “culinary burlesque” of pour-over bars, with their solemn baristas and potted succulents. “It’s dress-up,” he said.
Those settings and presentations, he said, send the wrong message: that good coffee must also be expensive and fetishized.

I drink a lot of coffee. At work I’m known to drink 40 or 60 ounces in a day. I also like specialty coffees, dating back to when I lived in Portland and patronized the Stumptown on Belmont.

As someone who drinks black coffee I like the idea of a no frills establishment. But I also feel the piece’s opposition between cheap good coffee and expensive faux-good coffee is a bit much. In How Pleasure Works Paul Bloom elaborates on something that we know intuitively: it is not always the sensory aspect of how something makes you feel, but also the intellectual aspect of what something is in a more contextual and broad sense. I would pay a lot for legitimate Falernian wine without even knowing what it tastes like. To drink like Cicero would be enough.

Yes, sometimes you want the $1 coffee. But sometimes you want the burlesque experience.

Living as Loki, friendship before Ragnarok

Posted on by Razib Khan

In Norse mythology Loki is a trickster frost giant who also plays a god. His relationship to the Aesir is complicated, but at the end of days when the world is nearing its final hours he is fated to stand against his erstwhile companions. I do not know much about the Marvel comics adaptation of Loki, though I have seen the films, and this element of alternating between good and evil is evident onscreen.

Does the fact that Loki is destined to stand against Odin negate all their experiences together? Is the full measure of a life the final act? I don’t think so.

Today we live in an age when he center is not holding. Politics and public life are polarizing. Apocalyptic language is in the air. Barack Obama was a socialist, a Communist, a Muslim. Now Donald J. Trump is the worst, thing, ever. And so on. There are two teams, and if you do not choose a team, you have lost the game before it is played. My pessimism about the possibility for a reinvigoration of a broadly liberal democratic order are for another post.

Recently my friend Heather Mac Donald wrote about her experience with protesters at Claremont McKenna. Her description of the student body’s hysterics are almost anodyne in how predictable they behaved. Rather, I was struck by how much invective Heather directed toward the silent faculty:

…Those professors also maintain that to challenge that claim of ubiquitous bigotry is to engage in “hate speech,” and that such speech is tantamount to a physical assault on minorities and females. As such, it can rightly be suppressed and punished. To those faculty, I am indeed a fascist, and a white supremacist, with the attendant loss of communication rights.

Of course not all faculty have abandoned classical liberal ideals. Nicholas Christakis and Alice Dreger are by any definition progressive liberals, but also adhere stridently to ideals of freedom of thought and speech. But both have been subject to abuse and personal attacks. They clearly fight on not because they are assured of victory, but because they believe in the justness of their cause.

Many of my liberal friends express some exasperation that I identify as conservative. But the fact of the matter is that the far Left writes off much of this country, and many of my friends, and arguably me, as a white supremacist and a fascist. Ours are not thoughts worth having in the eyes of the heirs of repressive tolerance. My liberal friends, being broad minded an of a tolerant bent, do not have sympathy with repression of thought. But at the end of the days when sides are taken what side will they choose?

I think here of an academic who is jaded and contemptuous of the infantile antics of the campus Left. He is worried that their provocations will result in the academy being targeted by the political Right. He does not relish conflict. Like me, he wants to be left alone to explore the topics which interest him. We share a mutual interest in evolutionary genetics. But, when and if the fight comes he does admit he must march with his colleagues, no matter how loony, and defend his side.

We both wish the world were not this polarized. But what we wish is not always what is. But until Ragnarok we can continue to drink beer and fight our battles shoulder to shoulder as friends. Neither of us want the Ragnarok of this liberal democratic republic to come, and I still hope it doesn’t. But we both understand that on that day we’ll be on different sides. And I’m OK with that. Life is not perfect, we do the best we can.

Addendum: Cool trailer:

Just because it’s not hereditary does not mean you can affect it

Posted on by Razib Khan

A comment below from Andrew:

Love to see a post about which human traits worth caring about are notable for having little or no hereditary component. It is all good and well to know what we cannot change, but it makes more sense to focus personally and as a parent on those things that aren’t genetically preordained.

This is a common sentiment I’ve seen. If you haven’t read The Nurture Assumption, please do so. I’d say a substantial reason I think that The Blank Slate is a good book is that Steven Pinker promoted Judith Rich Harris’ work.

With that out of the way: the implication in the comment above is that hereditary traits are the ones you have least control over, so you should focus on the non-hereditary traits. To some extent there is truth in this. Micronutrients are important. You don’t want to turn you children into cretins.

But a major problem with the idea that we can impact environmental impacts on characteristics is that on many traits we don’t know what those environmental impacts are. You can take a behavior genetic model and come to the following conclusion: within the population 50% of the variation is due to genes, 40% of the variation is due to non-shared environment, and 10% of the variation is due to shared environment (parents). We don’t really usually know what the non-shared environment means. It might be just developmental noise. It might be epistatic genetic effects. Or, in relation to behavior, it might be peer group, as Judith Rich Harris asserts.

We just don’t know. What that means is that the hereditary components are what you have legitimate effective control over through mate choice. And shared environment. These two combined are not nothing. And of course there is the impact of nation or community on the environmental in which propensities are expressed.

Addendum: The non-shared environmental variance was once explained to me as a “noise” factor. Just to give you a sense of how well we understand it.

“Rationalists” are the worst, except for all the alternatives

Posted on by Razib Khan

A slight controversy about the “rationalist” community has surfaced on the internet recently. Scott Alexander can point you to the appropriate places to bone up on what’s going down, as well as a relatively short apologia for his community.

First, the self-description of the community as “rationalists” is in my opinion a big problem. It’s rather like the aught era attempt to redefine the atheist “community” as “brights”. No one thinks of themselves as a “dim,” and unless you are a little too into your Nietzsche there aren’t that many self-described irrationalists.

I became socially close to many people in the Bay area rationalist community in the late 2000s. Many I still consider friends. I won’t belabor my differences with them in terms of optics and marketing, as well as substantive critiques of the role of group-think in any human community, as well as strong disagreements in relation to inferences made about what is and isn’t “rational” (there was for some time a vogue for polyamory in this subculture, which some justified as the rational position; I was skeptical).

At the end of the day I put less emphasis on reflective analysis in dictating the course of my life at any given moment than self-described rationalists. Reasonable, even rational, people may disagree on these issues.

But I do have to say that you don’t get a good sense of the community from blog posts or media reports. Meeting together in social situations the group dynamic is far different than most other congregations of humans you’ll encounter. The rationalists I know are some of the most open-minded and non-judgmental people you could meet. They are less likely than the average bear to write up screeds on the internet. They entertain alternative hypotheses with the appropriate level of cold-bloodedness, while attempting to work out the implications of their utilitarian ethics to their logical conclusions.

This does not mean that rationalists are not horrible people. They are people, so many are horrible. They are simple less horrible, in my experience. They may not achieve the state of “less wrong,” but in general they achieve the state of less unhinged and less emotive.

Some of this is due to striving toward a particular set of values and community norms. But some of this is I believe because the community attracts a particular personality profile. In Simon Baron Cohen’s classic typology the rationalist community is highly enriched for systemizers. The rationalists entertain ideas which might strike normal people as bizarre, but that’s part of the method to their madness. Because their personality profiles are sharply differentiated from normal distributions many of the social dynamics that any behavioral economic game would find in other test populations might not apply among the rationalists.

Note: I believe rationalists do engage in less “signalling” dynamics than you’d expect, because they’re less keyed in to cues from other humans, including those in their own community.

Why only one migrant per generation keeps divergence at bay

Posted on by Razib Khan

The best thing about population genetics is that because it’s a way of thinking and modeling the world it can be quite versatile. If Thinking Like An Economist is a way to analyze the world rationally, thinking like a population geneticist allows you to have the big picture on the past, present, and future, of life.

I have some personal knowledge of this as a transformative experience. My own background was in biochemistry before I became interested in population genetics as an outgrowth of my lifelong fascination with evolutionary biology. It’s not exactly useless knowing all the steps of the Krebs cycle, but it lacks in generality. In his autobiography I recall Isaac Asimov stating that one of the main benefits of his background as a biochemist was that he could rattle off the names on medicine bottles with fluency. Unless you are an active researcher in biochemistry your specialized research is quite abstruse. Population genetics tends to be more applicable to general phenomena.

In a post below I made a comment about how one migrant per generation or so is sufficient to prevent divergence between two populations. This is an old heuristic which goes back to Sewall Wright, and is encapsulated in the formalism to the left. Basically the divergence, as measured by Fst, is proportional to the inverse of 4 time the proportion of migrants times the total population + 1. The mN is equivalent to the number of migrants per generation (proportion times the total population). As the mN become very large, the Fst converges to zero.

The intuition is pretty simple. Image you have two populations which separate at a specific time. For example, sea level rise, so now you have a mainland and island population. Since before sea level rise the two populations were one random mating population their initial allele frequencies are the same at t = 0. But once they are separated random drift should begin to subject them to divergence, so that more and more of their genes exhibit differences in allele frequencies (ergo, Fst, the between population proportion of genetic variation, increases from 0).

Now add to this the parameter of migration. Why is one migrant per generation sufficient to keep divergence low? The two extreme scenarios are like so:

  1. Large populations change allele frequency very slowly due to drift, so only a small proportion of migration is needed to prevent them from diverging
  2. Small populations change allele frequency very fast due to drift, so a larger proportion of migration is needed to prevent them from drifting

Within a large population one migrant is a small proportion, but drift is occurring very slowly. Within a small population drift is occurring fast, but one migrant is a relatively large proportion of a small population.

Obviously this is a stylized fact with many details which need elaborating. Some conservation geneticists believe that the focus on one migrant is wrongheaded, and the number should be set closer to 10 migrants.

But it still gets at a major intuition: gene flow is extremely powerful and effective at reducing differences between groups. This is why most geneticists are skeptical of sympatric speciation. Though the focus above is on drift, the same intuition applies to selective divergence. Gene flow between populations work at cross-purposes with selection which drives two groups toward different equilibrium frequencies.

This is why it was surprising when results showed that Mesolithic hunter-gatherers and farmers in Europe were extremely genetically distinct in close proximity for on the order of 1,000 years. That being said, strong genetic differentiation persists between Pygmy peoples and their agriculturalist neighbors, despite a long history of living nearby each other (Pygmies do not have their own indigenous languages, but speak the tongue of their farmer neighbors). In the context of animals physical separation is often necessary for divergence, but for humans cultural differences can enforce surprisingly strong taboos. Culture is as strong a phenomenon as mountains or rivers….

Why are so many of us “star-men”

Posted on by Razib Khan

Seven years ago I wrote 1 in 200 men direct descendants of Genghis Khan. It’s the most popular post I’ve ever written. As of now there have been 630,000 “sesssions” (basically visits) on that page alone. I suspect that many more have read my summary of The Genetic Legacy of the Mongols, the original paper on which it was based, than that paper (though it’s a good paper, you should read it).

At the time I wrote that people often asked me if I was a descendent of Genghis Khan. That seems unlikely on the paternal lineage. My Y chromosome is R1a1ab2-Z93. This is typically found in South Asia, and among Iranian peoples, as well as in the Altai region of western Mongolia. It is not common among Mongols though, even if it is found amongst them, likely due to gene flow from the west. The particular branch of R1a1a that I carry has been found in ancient remains from the Srubna culture of the eastern Pontic steppe. As a friend of mine might say, I am the scion of marauders from the steppe, even though not Genghiside ones. The fact that I have the last name Khan is simply a legacy of the custom whereby South Asian Muslim lineages of a particular status accrued the surname to denote their position within Islamicate civilization.

But though I am no direct descendent of Genghis, it turns out that my Y chromosome shares a similar history. The figure to the left is focused on European Y chromosomes, and at the top you see various “R” lineages. It turns out that R1b and R1a are both basically subject to the same explosive dynamics as the Genghis Khan haplotype: both exploded into star phylogenies relatively recently in time. Trees of the R1 lineages always show them to exhibit a rake-like pattern. This is due to the fact that starting from a small base they expanded so rapidly that they did not develop the intricate node-structure you see in lineages which accrued mutations at a more normal pace.

What could have caused such explosive growth? We know why Genghis Khan and his sons left so many descendents: conquest yielded social status. For many generations having a male Genghiside bloodline was highly effective as a means to gain bonus points when attempting to scale the summits of power and wealth. This was even true in the Muslim regions of Central Asia, despite Genghis Khan’s negative impact on Islamic civilization (Transoxiana arguably never recovered from this period).

We don’t have anything like the “Secret History of the Indo-Aryans” to explain the emergence of these older star phylogenies. In The Horse, the Wheel, and Language, David Anthony argues that mobile populations domesticated the horse, and used that as a killer cultural advantage to spread their Indo-European language. In his book from the 2000s Anthony argues for elite transmission of language by the Kurgan people. But more recently he has been persuaded by genetic work which suggests massive population displacements and migrations into Europe during the late Neolithic and early Bronze Age.

Unfortunately the timing doesn’t work from what I can tell. The expansion of groups like the Corded Ware seem to pre-date the emergence of the steppe chariot toolkit by many centuries. It does so happen that the chariot was invented in the region where R1a1a2b-Z93 was also found to exist. So I suspect this “Scythian” R1a lineage did sweep across much of Central-South Eurasia thanks to the horse and the wheel. But a technological explanation is more difficult for the rest.

I will posit another speculative answer, stealing the idea from Snorri Sturluson. He believed that the gods that were remembered by his pagan Norse ancestors were at one point men of great renown and fame. Kings of yore. Over time they had been deified, and legends had grown up around them. Sturluson may have been right. Perhaps the Indo-European gods recollect the forefathres of R1a and R1b. What was there advantage? Perhaps it was a hierarchical stratified social structure which brooked no individualism against the interests of the lineage unit? It may be that asabiyya is worth more than a chariot?