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Does this model of Christianity and other sociological factors changing Roman IQ via polygenic pressures account for the massive population changes paleo-genomics has also revealed in chronological parallel?

The IQ changes from the Republican to Imperial to Late Antiquity map exactly the genealogical changes we see from native Latin in the Republican era, to mass Levantine (“Oriental”) migration in the decadent period, to the collapse cleansing urban centres and bringing a fresh influx of Nordic blood.

The Italians of the Republican era are genetically closest to modern day Catalans and Lombardians (South Europeans with 0-5% MidEast admixture - highEEF w/30% WSH); the Imperial era Italians in urban centres were basically mestizos, up to half Levantine, and closest to modern day Maltese, Greeks, Sicilians.

Elementary application of deduction would suggest that actually paleo-genomic factors are stronger, and the relatively large intra-European gap we see between North and South Italy can be explained by the difference in the size of the genetic legacy from the destructive migration of the Imperial period.

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Love all this.

I think it's also worth discussing Civil Wars (probably plague too but lets leave that aside). The end of the Republican era was one of untold slaughter of Romans. Not just the utterly devastating wars we know of Ceaser and Octavian, but going all the way back to the Social War and the rest. In a Civil War everyone that dies is Roman. People noticed how thinned out the talent pool got by the end.

A similar process happened during the Crisis of the Third Century.

Christianity it seems to me was part of a broader attempt to solve the Civil War problem. The explosion of religions with similar characteristics around the world probably owes to this same problem amongst many other factors. How do you attain relative internal peace and continuity in a large empire that lasts longer than a single personality?

Paganism seems fine enough working at the city state level (where people know one another) and perhaps during expansionary periods there is enough loot to spread around amongst grasping pagans. But how does one settle into something at scale that lasts.

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How exactly did female hypergamy have a negative impact on cognitive capacity of the population? Seems very counterintuitive to me.

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I have no fundamental reservations about GWAS studies. On the contrary, I find them highly interesting.

I also find the study by Piffer, Dutton, and Kirkegaard (2023) very interesting, but I do not think that the interpretation is justified in any way.

The sample of ancient Romans was divided into five groups and the number of individuals was

Pre-Iron Age 16

Republic 11

Imperial 48

Late Antiquity 24

Medieval 28

Contemporary 41 (page 2 mentions 33)

It is unclear how the subsamples were composed, but it is clear that they are by no means a representative sample for the period in question. On this extraordinarily weak basis, no meaningful conclusions can be drawn about cognitive development.

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I have addressed a different aspect of this study here:

https://open.substack.com/pub/kirkegaard/p/ancient-genomics-ama-with-davide?r=29yrch&utm_campaign=comment-list-share-cta&utm_medium=web&comments=true&commentId=39283088

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> Christianity failed to save the Empire and may even have hastened the eventual collapse.

It probably saved its Eastern half.

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I know practically everyone who reads this magazine is likely a materialist, but I have to ask the question:

What if Christianity actually was the intervention of God in the world? What if our societies trended towards violence, warfare and genetic degeneration, and the gospel of Christ is both the answer to our practical problems over the long term, and a message from the divine of our salvation?

What if both of those are somewhat similar?

Anyway, thanks for doing this excellent research. Interesting findings even though I disagree with many of your hasty conclusions.

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"By favoring monogamy and, conversely, by limiting male polygyny and female hypergamy;"

Why would this intensify selective pressure for intelligence.

Also, these scores are insane. Tell me someone has them for other groups/periods. Please,tell me you have them for Greece from Mycenaean period all the way up until late antiquity.

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