The world is more than two categories

A post from Kevin Drum, Once Again, a New Book Debunks Some History I Never Knew In the First Place,* made me wonder a few things. First, Kevin’s confusion:

Am I befuddled by history? Or by historiography? Or do I need a different word altogether?

Until five minutes ago, before I read this book review, it never would have occurred to me that white women were anything less than full partners with men in the white supremacy of the antebellum South. I have never read anything that even remotely suggests such a thing. And yet, apparently this has been a widely held belief—and not just by the masses, but by practicing historians as well.

Additionally, today I listened to the Extremeley Offline podcast where Zaid Jilani moderated a conversation between Liz Bruenig and Jon Chait, and Jilani talks about some of his confusion and discomfort with the racial dichotomies that have recently emerged in the United States (though our politics are very different it seems we have had the same experiences and reactions in relation to this). For example, all nonwhites are now “people of color,” set against whites. The three present a thesis that a dominant form of conceptualization of the world on the modern Left is between the marginalized and those who are not, and so you have dichotomies. People of color vs. whites. Women vs. men. The queer vs. straight. And, of course, the poor vs. the rich.

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The age of prenatal genetic screening is here (let’s call it that!)

In the spring of 2010, I went to the studios of KQED in San Francisco to record an interview with a radio show on the BBC about PGD. Preimplantation genetic diagnosis. I haven’t thought much about the issue in the near ten years since then. Which in a personal sense certainly reflects my luck and circumstance.

But I’m thinking about the issue after reading this story from Emily Mullin, We’re Already Designing Babies: Expanded genetic testing of embryos represents a new era of family planning. But how far should the technology go?:

JJill Pinarowicz’s life has been shaped by a mutation in her mother’s DNA. The genetic error gave her two brothers a rare disease called Wiskott-Aldrich syndrome….

Both of Pinarowicz’s brothers passed away from complications of the disease. One died as a toddler, before she was born, and her other brother died at age 18, when Pinarowicz was a teenager.

Pinarowicz thought it would be too risky to have her own children….

The technique is called preimplantation genetic testing (PGT). By using PGT together with in-vitro fertilization, Pinarowicz and her husband had a healthy son in May 2017.

An incredible “feel-good” outcome so far. And not surprising. I have become more conservative about technology since I first started writing on the internet in the early 2000s, but I will never oppose these sorts of genetic technologies that allow couples whose offspring are at high risk of developing serious debilitating conditions to avoid these scenarios. But the magnitude of how common this now took me aback:

The U.S. Centers for Disease Control and Prevention (CDC) reported in January that PGT was used in 22 percent of IVF cases in 2016, up from just 5 percent in the previous year.

Since the last statistic Mullin could find was from 2016, it’s almost certain that the proportion is greater than 22 percent today. The numbers for 2018 seem difficult to find, but it seems likely that ~75,000 live-births per year in the USA are now due to IVF. Worldwide there are in the range of 10 million humans alive today due to IVF.

How relevant IVF is to fertility varies by social and demographic variables. I know a fair number of people who have done IVF. The average age of a mother at her first birth is 32 in San Francisco and 31 in Manhattan. As many of you probably know many options relating to fertility and genetic testing come “online” for American insurance companies at age 35.

When you transform blue-sky exotic basic science into mass technology they become far less controversial. One of the major themes of Carl Zimmer’s new book, She Has Her Mother’s Laugh, was the vocal and mainstream nature of 20th-century eugenics. A major criticism of Robert Plomin’s Blueprint is that it was resurrecting genetic determinism. Let me quote Mullin:

In Iceland, for instance, the widespread availability of prenatal genetic testing has meant that nearly 100 percent of women choose to abort a fetus with Down syndrome, which has led to a near eradication of babies being born with the condition.

What is in a word? Something in the future is worrisome. Something that professional dual-income-no-kids couples do in their attempt to attain the classic bourgeois lifestyle is not so worthy of comment? Outside of the pro-life movement the discussion of the ubiquity of screening for Down syndrome seems rather muted, even though it is widespread. While we may furrow our brows over decisions made based on polygenic risk scores, the reality is that the age of Mendelian screening is here. It is not speculative science, but applied medicine.

Call it what you want to call it.

Open Thread, 02/24/2019


Probably don’t watch this if you are hungry. It’s on Netflix.

The latest episode of The Insight featured a very long discussion with Jeffrey Rose. If you are curious about the relationship of southern Arabia to the cultures of northeast Africa during the Middle Paleolithic, check it out!

The Freemasons. Not the deepest book. But interesting.

The Linked Selection Signature of Rapid Adaptation in Temporal Genomic Data.

Accurate inference of tree topologies from multiple sequence alignments using deep learning.

Human genetic disease is greatly influenced by the underlying fragility of evolutionarily ancient genes.

Unbiased estimation of linkage disequilibrium from unphased data.

China’s CRISPR twins might have had their brains inadvertently enhanced. The title is just plain wrong. Unfortunately the piece “traveled” and now I’m seeing it cited at places like National Review, Eugenics-Engineered Babies’ Brains Changed by CRISPR.

Supreme Court Delivers Unanimous Victory for Asset Forfeiture Challenge.

World’s largest bee, once presumed extinct, filmed alive in the wild.

David Slone Wilson has a book out, This View of Life: Completing the Darwinian Revolution.

‘Austerity, That’s What I Know’: The Making of a U.K. Millennial Socialist.

Ancient whole genome duplications and the evolution of the gene duplication and loss rate.

Recombination and mutational robustness in neutral fitness landscapes.

We Must Defend Free Thought. This is really about Scott Alexander, who is becoming too influential for the tastes of some.

Reihan Salam new President of Manhattan Institute.

Viruses rule over adaptation in conserved human proteins.

Also, if you haven’t, you might check out my RSS, Facebook, or Twitter (or my aggregator page) if something happens to this domain temporarily.

Ancestral proto-Eurasians may have had wavy hair

Australian Aboriginal child photographed in the late 1850s

The above chart is from The Simons Genome Diversity Project: 300 genomes from 142 diverse populations. The basic outlines of this tree were evident as far back as L. L. Cavalli-Sforza. But there were always small details that caused issues. In particular, were East Asians a more natural clade with Australasians or with Europeans? Today with both ancient DNA and whole-genome analyses two things are clear which might have been confounding earlier analyses:

  1. There has been gene flow between many East Asian and European populations. If you look closely at the ancient DNA work it is clear that East Asian gene flow is present in Mesolithic hunter-gatherers. Conversely, many northern Chinese have show low levels of West Eurasian ancestry (I suspect mediated through Mongols and Turks).
  2. The peoples of Australasia have Denisovan ancestry, which is distinct from anything found in East Asians and Europeans (small trace proportions of Denisovan in the former notwithstanding).

With these considerations accounted for, it seems clearer that the peoples of Oceania and East Asia descend from a common group that pushed from the west. And, the most ancient substratum in South Asia is also part of this broad family of peoples, who diversified in the period between 45 to 55 thousand years before the present. This is in contrast to the peoples to the west, who gave rise to Ice Age Europeans, Middle Easterners, and more distantly the “Ancient North Eurasians” who seem to be the first settlers of Siberia.

To understand the context for the emergence of characteristics and traits one has to understand the demographic histories and relationships between people. We are coming close to establishing the latter with good certainty for most groups. Though the sea levels separated New Guinea from Australia only within the last ~10,000 years, genetic work suggests that the differentiation between highland Papuans and Australian Aboriginals long predates this. If I had to hazard a guess I’d suggest that the huge ecological differences were probably critical in reducing gene flow between the wet and warm highlands of Sahul, and the broad deserts that occupied what became Australia.

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“Out of Africa” in 2019

The figure to the left is from Paleolithic DNA from the Caucasus reveals core of West Eurasian ancestry. It is a graph which captures general features of human population historical relationships as we understand them today. Or at least the model fits the data (remember, many models may fit the data!). The graph is complex…but even within the text of the preprint, the author admits that it is characterized by simplifying assumptions, which nevertheless are informative of some general dynamics and processes (e.g., pulse admixtures).

To some extent, the whole last generation or so has been characterized by the victory of a simplifying assumption that captures general truths about the past, with the accumulation of modifications on the margins as more nuanced results enter the picture. The simplifying assumption I am talking about here is the “out of Africa” 50,000 years ago with a total replacement of all other human lineages framework.

By the last quarter of the 20th century, a combination of archaeological and genetic evidence pointed to the likelihood of a massive bottleneck and expansion of humans outside of Africa in the relatively recent past. In the pre-genomic era, the tools were coarse, from uniparental lineages, classical markers, microsatellites, morphometric analyses, as well as archaeological surveys. But, they strongly pointed to massive expansion and population turnover ~50,000 years ago. This, combined with a line of thinking which suggested that Neanderthals were “evolutionary dead-ends” led to the thesis that there was a total replacement.

To a great extent, this model seems to hold up in the broad sketch. But not to an absolute and total degree. Some paleoanthropologists and geneticists were pointing out for decades that the tools we had could not exclude the possibility of admixture at lower fractions with earlier lineages in Eurasia on purely statistical grounds. These scholars were correct, as it turns out. There is now high confidence that in the range of 1-5% of the ancestry of non-Africans derives from highly diverged “archaic” lineages, Neanderthals and Denisovans. The fraction is low enough that more coarse methods did not definitively pick them up, and without ancient genomes, the “game of inference” was not dispositive in either direction. This, despite the fact that these Eurasian hominins’ ancestors seem to have diverged from those of modern humans ~750,000 years ago. Ultimately, scientists needed a physical ancient genome which they could compare to modern populations to come to this conclusion (before the Denisovan result, scientists had been noticing anomalies in Oceanian data for a decade or so but generally ignored it as beneath comment…a presentation was given an anthropology conference on archaic admixture in Oceania right before the Denisova cave paper).

The second major issue is that the massive expansion and bottleneck that occurred ~50,000 years ago may not explain all of the remaining ancestry that is not “archaic.” That is, there were many modern human lineages present 50,000 years ago. The major lacunae in the current model is a huge one: populations within Sub-Saharan Africa maintained larger population sizes throughout this event. And, anatomically modern humans predate this expansion by hundreds of thousands of years. From an archaeological perspective, a lower limit is 200,000 years ago, and an upper limit probably exceeds 300,000 years ago. Additionally, there are “deep lineages” within Africa which clearly predate the expansion 50,000 years ago. There is a strong consensus that the Khoisan people have at least some substantial ancestry that diverged more than 150,000 years ago from other humans, and tentative suggestions from several different research groups suggest that there are even more “basal” (deep divergence) lineages in parts of West Africa that the component within the Khoisan.

This does not even address the likelihood that some “archaic” ancestry persists within Sub-Saharan Africa just as it does outside of Sub-Saharan Africa.

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Reevaluating “multiple origins” for modern humans

Following up on the post below, The Deep Origins Of East African Hunter-Gatherers, as well as some discussions on Twitter, I think I want to do some clarification about where I think we are now. My thoughts shouldn’t be a surprise if you have read everything I’ve said, but I may not have put them all together in one place.

Around the turn of the century, nearly twenty years ago, the consensus had definitively turned against a “multiregional” origin of modern humans, toward one where an “out of Africa” migration ~50,000 years ago was paramount. Many people took the “paramount” part and simply asserted that we are all Africans descended from a population that flourished in the east of the continent about 50,000 years ago. There was a lot of circumstantial evidence to support this, at least spottily, from both archaeology and genetics. There were also problems and lacunae in both fields. But the data was spotty enough that the extreme position was defensible.

We now have a lot more information and need to update our model. First, most people agree that indigenous Eurasian hominins, Neanderthals and Denisovans, contributed to the ancestry of people outside of Sub-Saharan Africa. Additionally, it’s been evident for a long time now that the massive population bottleneck that is present in all non-African populations dating to ~50,000 years ago is far less evident in Sub-Saharan African genomes.

Finally, it’s pretty clear that humans with modern morphology were present within Africa for hundreds of thousands of years before the movement out of Africa.

Therefore, a new reevaluation of the old model that is converging is a possibility is that multi-regionalism was operative within Africa for hundreds of thousands of years, followed by a massive expansion on the northeast edge of Africa that resulted in most of the ancestry of other human groups outside of the continent, with some assimilation (e.g., Neanderthal). This is a far more complicated model than the older one, but sometimes the truth is more complicated than simplicity.

But I think we’ll probably need to make further modifications, and that’s because gene flow is not always unidirectional. Specifically, the Y chromosomal work, in particular, is strongly indicative of migration of lineages more typical of Eurasians expanding within Africa within the last 50,000 years. And, as a commenter on this weblog has pointed out, even the “deep lineages” within Africa, Y haplogroups A and B, show signs of massive expansion within the last 50,000 years.

This may mean that a population liminal to Africa and Southwest Asia underwent a very rapid expansion ~50,000 years ago. The replacement of indigenous lineages was far more thorough outside of Africa, with 5% or less assimilation in most places. But, it probably impacted Africa as well. Though a larger fraction of diverged modern ancestry persisted in Africans than Eurasian hominin ancestry in non-Africans. In other words, the high genetic diversity of Africans today, and particular groups like the Khoisan, is due to the mixture between an ancient migration from the same population that was the source of “out of Africa” in Eurasia and Oceania, and disparate deeply structured lineages within Africa, that date back 200-400 thousand years ago.

Additionally, I think some earlier “modern” lineages were assimilated in eastern Asia with the latest migration out of Africa. And, some of the ancestry within Africa probably predates the origin of anatomically modern humans, analogous to the case of Neanderthals and Denisovans.

Note: This is not that different of a model from Dienekes Pontikos’ ideas in the 2000s, More support for the Afrasian/Palaeoafrican hypothesis, at the high level. Basically the more evidence has come in, the less crazy his model has gotten.

The deep origins of East African Hunter-Gatherers


PNAs has a new paper out, Genomic evidence for shared common ancestry of East African hunting-gathering populations and insights into local adaptation. From what I can tell this was never a preprint, so it’s all new….

Or is it? Looking closely at some of the populations sampled, I’m about 85% sure that I saw a very early and preliminary analysis of some of these data (probably on a different SNP-chip) at ASHG 2012. I say this because I recall talking to the second author in front of the poster about an obscure hunter-gatherer tribe in Ethiopia that they had sampled. Unlike some graduate students he did not dodge my inquiries by standing away from the poster as if he was not associated with it!

Here is the abstract:

Anatomically modern humans arose in Africa ∼300,000 years ago, but the demographic and adaptive histories of African populations are not well-characterized. Here, we have generated a genome-wide dataset from 840 Africans, residing in western, eastern, southern, and northern Africa, belonging to 50 ethnicities, and speaking languages belonging to four language families. In addition to agriculturalists and pastoralists, our study includes 16 populations that practice, or until recently have practiced, a hunting-gathering (HG) lifestyle. We observe that genetic structure in Africa is broadly correlated not only with geography, but to a lesser extent, with linguistic affiliation and subsistence strategy. Four East African HG (EHG) populations that are geographically distant from each other show evidence of common ancestry: the Hadza and Sandawe in Tanzania, who speak languages with clicks classified as Khoisan; the Dahalo in Kenya, whose language has remnant clicks; and the Sabue in Ethiopia, who speak an unclassified language. Additionally, we observed common ancestry between central African rainforest HGs and southern African San, the latter of whom speak languages with clicks classified as Khoisan. With the exception of the EHG, central African rainforest HGs, and San, other HG groups in Africa appear genetically similar to neighboring agriculturalist or pastoralist populations….

Some of this stuff was vaguely predictable a long time ago. There is a strange tendency in older data and results for hunter-gatherers such as Pygmies and San Bushmen to be closer together genetically against agro-pastoralists and farmers. Additionally, the two most deeply diverged Y chromosomal haplogroups, A and B, tend to be found in African hunter-gatherers in particular. At least at high frequencies.

The main phylogenetic result of this work is some other isolated hunter-gatherers in eastern Africa, more obscure than the Pygmies, Hadza, and San Bushmen, also seem to show deep affinities that set them apart from demographically dominant groups such as Nilotic pastoralists and Bantu farmers.

This is not surprising though in light of ancient DNA. A few years back Pontus Skoglund’s paper showed that there was likely a preexistent relatedness cline in East Africa between the peoples who were present in Ethiopia before the arrival of Eurasians and south toward the ancestors of the modern Khoisan groups in southern Africa.

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The rise of the childless class

Due to the recommendation of a reader of this weblog I’ve been listening to the audiobook of John Keegan’s A History of Warfare. I am good at reading a text. I am not so good at patiently paying attention to the narration of someone speaking.

But with that said, one passage that stuck out at me is where Keegan talks about the tension between the Christian professional class of secular and religious priests and the military nobility of early medieval Europe. Priests and monks were the Christianized cultural descendants of the Roman elite, which engaged in war, but generally focused on literate self-cultivation so as to signal their acceptability to polite society (this was especially true after the 3rd-century emergence of an Illyrian military elite that took up the martial responsibilities of the Roman nobility). The post-Roman and early medieval ruling class, in contrast, was marginally literate at best, and with exceptions took after German warlords in their practices if not their professed beliefs.

Keegan notes that numerically the religious caste and the military caste were balanced, adding to the tension which was punctuated by events such as Humiliation at Canossa which occurred in 1077 AD. But my interest and thoughts were piqued by the realization that this balance between priestly and military castes is neatly paralleled in many societies. It occurred among ancient Indo-Europeans, and continued down into historical periods among Zoroastrian Iranians, and continues down to the present day in India among Hindus. In China, the situation is somewhat different, because the bureaucratic and civilian gentry had traditionally subordinated any military element. The famously civilian Song dynasty was founded by a successful general. But in Japan arguably the large Buddhist establishment coexisted with the samurai class, while in the Islamic world the ulema serves to buttress military caste.

And yet there are differences between these groups. The Western Christian priesthood and the Dharmic religious class exhibit a degree of detachment from normal society due to their celibacy. This is not the case for the religious class of Muslims, who marry and have children, just as Protestant ministers, Jewish rabbis, and most Eastern Orthodox priests, do. Though Hindu priests generally marry, an ancient tradition of celibacy exists in Indian culture and persists within Hinduism, and this was transmitted throughout the world via Buddhism.

The Buddhist tendency to produce large self-supporting and independent institutions which supported celibate monks and nuns was one of the main reasons that the Confucian elite objected to the religion: it undermined family life.

The difference between religious and intellectual elites which have a normal family life and those which don’t remind me of a close friend who is a very productive and prominent (for his age) professor at an elite university. Now that he is settled down with someone, the consideration of children has emerged. If they are able to have children, likely a single child due to age, my friend expects that his life will change in many ways. This will impact his work. In fact, when it seemed likely that he was never to have children I did tell him that in a way it was a benefit to him, as he could pursue high-risk research and allocate his time geared purely toward maximizing human knowledge.

Aristotle married and hand children. Plato does not seem to have done so. I think the difference seems entirely reflected in the character of their philosophies. Christianity and the Dharmic religions have had large numbers of religious-intellectual professionals detached from worries of family life as monks across their history. In contrast, Jewish rabbis, Muslim ulema, and Confucian scholars have all had to concern themselves with family life.  I would say on the whole Christianity and the Dharmic religious have concerned themselves more with abstruse philosophical issues around metaphysics, while the latter religions have focused more on the organization of prosaic life so as to further “the good” as they understand it. Judaism, Islam, and Confucianism are fundamentally religions of orthopraxy, not orthodoxy.

When I say “family life”, I really mean children. Children change you in many ways. For parents, they are the biggest contributions you will make to the human race. Having children can cure many of abstract radicalism and hunger for philosophical speculation.

Of course, not all single people are reading thick scholarly tomes with their marginal time. Most American single people who will never have children are rather stupid, and so focus on consumption, sex, and assorted distracting leisure. They are hedonic machines. But, a minority are devoted to causes. To society. And they have a lot more time than those of us with family obligations.

Over the last generation American society has changed a great deal when it comes to children (or the frequency of):

Delaying marriage is related to delaying childbirth. The median age at first marriage has gone from 20.6 to 27.4 for women and from 23.1 to 29.6 for men since 1967. Age at first birth increased as well. Most babies are born to a married couple, so it is natural to see shifts in the percentage of adults who live with no children in particular age groups.

The largest change in the proportion of adults living without children happened among those aged 18 to 35. In 1967, the majority of 18- to 24-year-olds had children living with them (53.3 percent) but by 2016, less than a third did (31.2 percent).

The changes are even more dramatic among 25- to 34-year-olds. In 1967, 23.9 percent in that age group did not have their own children under their roof. By 2016, the share more than doubled to 61.5 percent.

What are the implications for a much larger number of American adults in their prime years living in households without children?

Societies are complex. I think the existence of a large number of celibate adults as a persistent institution probably resulted in some unique aspects of Western Catholic and Indo-Buddhist cultures. To be frank, I think a sort of strange and peculiar unmooring from reality can occur. The reflexive ridiculousness of Zen or the openness of hyper-rationalism of Thomas Aquinas are both products of this. This isn’t bad. The flourishing of science in Western Europe may have been enabled by the independent and detached institutions of Catholicism.

Today in much of the world we see a different phenomenon from religious institutionalized celibates: the existence of a large number of childless adults outside of a strong institutional framework that channels their energies and leisure. I think a consequence of this may be some peculiar enthusiasms for various radical ideologies.

Open Thread, 2/18/2019

Peter Turchin’s Ages of Discord is now a free rental if you have Amazon Prime (otherwise you will be prompted for a Kindle Unlimited subscription). If you are interested in the kind of stuff I talk about, I highly recommend all of Peter Turchin’s work. For readers of this weblog Historical Dynamics: Why States Rise and Fall and War and Peace and War: The Life Cycles of Imperial Nations would be of most interest.

Speaking of Peter, check out his recent blog post, An Anarchist View of Human Social Evolution, which is basically a critique of the two of scholars and an essay, Are we city dwellers or hunter-gatherers? The interesting sociological aspect is that one of the scholars is a pretty unpleasant disputant with critics on social media…and that seems to redound to his fame and influence. Unfortunate incentives.

An Honest Living: What is it like to go from a tenured professorship to an hourly wage driving buses? This piece tries to make sense of an unusual transition. The author is, to be frank, kind of a dick. But there are lots of people with unpleasant and intolerable personalities in academia.

President’s Day sale and DNAGEEKS. Put in the code “PREZ” and you are good to go.

Speaking of presidents, you probably know about The Age of Jackson. A more recent book, The Age of Lincoln is worth reading. And, if you want to get more contemporary views for and against Jacksonianism, The Rise of American Democracy: Jefferson to Lincoln and What Hath God Wrought: The Transformation of America, 1815-1848.

The post below, The End Of America As The World As We Know It, is gated. But the first two posts should be free. And since the gating is leaky if you want to deal with the hassle you should be able to figure out how to get access (I’m going to make them free after 30 days as well).

The biography of Maximinus Thrax is on sale as Kindle. A lot of the Roman history stuff that is discounted is kind of like a Wikipedia entry, but this biography comes from a serious scholar and has some reviews that are positive from legitimate people. Thrax is a bit of a turning point character, ushering in the period when the Roman Empire was under serious threat from without and within.

Jussie Smollett. I wish there were betting markets for this sort of stuff. Also, those guys were shredded.

More than 26 million people have taken an at-home ancestry test. A bit of an update on the piece David Mittelman and I worked on last year, Consumer genomics will change your life, whether you get tested or not.

What ancient DNA tells us about caste. David Reich was in India for a bit talking about his work. It seems that they’re ready to uncoil their work soon enough. I’ve been told that he said a draft of the paper was written, so it’s probably going through internal revisions with collaborators.

This Mediterranean diet study was hugely impactful. The science has fallen apart.

The Making of a DNA Detective CeCe Moore, an amateur genealogist turned professional, helps police crack decades-old cases.

If you are on Twitter, Thomas Chatterton Williams is worth following.

For those of you who have read this blog since the beginning, you know that Ramez Naam is a friend. How to decarbonize America — and the world.

Mitogenomic evidence of close relationships between New Zealand’s extinct giant raptors and small-sized Australian sister-taxa.

Radiocarbon dates and Bayesian modeling support maritime diffusion model for megaliths in Europe.

A ‘Denisovan’ genetic history of recent human evolution.

A journalist is tweeting out old, and likely false, information, and another journalist is pointing out how you shouldn’t trust this result. Unfortunately, the original tweet-out is getting more RTs and likes than the refutation of the source and the credibility of the result.

I don’t normally read a book such as The Souls of Yellow Folk. First, it’s too much like a memoir, and I don’t care about other peoples’ memories. Second, I am on the same wavelength about most of these sorts of issues as Wes Yang, and I didn’t think I’d encounter anything novel or that pushed me to new views. But Yang is a good writer. Reading on the strong recommendation of a friend.

This week on the BrownCast I’ll be posting a conversation about Native Americans and nationalism with a lawyer.

Noah Smith says replace listening to podcasts with audiobooks. The problem I see with this is when it comes to books I have to give singular attention…so if I wanted to pay attention I’d just read the book. Podcasts are things that are less dense and contingent and I can sample in and out.

New York Did Us All a Favor by Standing Up to Amazon: Yes, Amazon’s departure will modestly hurt the city’s economy. But it’s also a victory against bad economic policy.

The Valentine’s Day episode of The Insight was fun. This was a conversation we could have had for three hours.

Speaking of academics who are irascible, Bob Trivers is burning up Twitter. Worth a follow.