I've just discovered the Y-chromosome bottleneck

[GarlicAnything]

When reading that patriarchy's approximately 5,000 years old, I haven't found serious justifications for it. Arguments seemed mostly to be about men being buried with posher grave goods (but women have been buried with equally swanky goods after that) and a reduction in 'venus' icons (but we don't know what they were for, and goddess worship doesn't prove anything anyway).

It never occurred to me to look at DNA. Here it is, though it happened more like 7,000 years ago. Google says:

The Neolithic Y-chromosome bottleneck was a sharp drop in male genetic diversity that occurred globally between 7,000 and 5,000 years ago. 1, 2]

What Happened

• Genetic collapse: Diversity in the male Y-chromosome dropped so fast that it looked like only one man reproduced for every 17 women.
• Only men affected: Mitochondrial DNA (passed down through mothers) showed normal, steady growth. This rules out general disasters like famines, plagues, or climate change. 1, 2, ]

Why It Happened
Scientists link this event to the shift from hunter-gatherer groups to farming and agro-pastoralist cultures. Two main ideas explain the drop: 1, 2]

• Patrilineal warfare: Early research suggests that wealth and power grew in male-dominated clans. Competing clans fought wars where entire family lines of men were killed, wiping out their specific Y-chromosomes. 1, 2, 3]
• Peaceful social structures: Newer models show that strict patrilineal and patrilocal systems (where land and names stay with male kin groups) can naturally reduce Y-chromosome diversity over time through normal social fission and unequal reproductive success, without requiring massive violence. 1, 2, 3]

One man reproduced for every 17 women! No matter what narrative we superimpose on this, it's quite an unpleasant picture. 17 women getting pregnant for each impregnator. Men indisputably took control over women and dictated which men they could reproduce with.

I think the 'peaceful' patrilocal societies must've been established by force, since I can't imagine women all over the world cheerfully leaving their homes to join strangers' harems.

Y-chromosome diversity recovered in a rapid spate of 'star-shaped' explosions from 5,000 years ago, when cities and city-states became the norm. People from what had been discrete rural settlements moved to the cities and mingled, then the city-states started fighting each other and taking each other's populations as prisoners. This resulted in more men and genetic mixture, with the star shapes being patterns of Y diversity radiating out from the city centres.

Sadly, it doesn't look like the men gave up controlling women's reproductive options and living conditions, although far fewer of them had as many as 17 wombs at their disposal.

Women made a patchy comeback at times. Now archaeology's giving up its sexist assumptions and re-examining grave finds, it's becoming clear that many societies throughout history have been female-led and matrilocal. I'm happy to note that this seems especially the case in Britain - our Celts buried more 'warrior queens' than they did in mainland Europe, for instance, though of course there's still much more to be discovered.

Absolutely: many HG settings were food-abundant. Even so, there were some that were not. A good example are the Selk’nam people who lived in Tierra del Fuego: a circumpolar, subfertile region, prone to the very occasional appearance of whale-carcasses. You can imagine the havoc that such a massive source of nourishment would unleash on a population that lived close to starvation. As a result, the men enforced a very strict order of distributing whale-meat. And you can maybe guess how women stood relative to men in Selk’nam life.

Thank you for this thread.

There is also the not infrequent system where the bureaucratic administrators of some powerful empires were eunuchs. They could be individually powerful and rich and respected, but they wouldn't have descendants to scheme for.

Meanwhile the leaders had large numbers of wives / slaves, so could build up a genetic legacy, but were also possibly more exposed to the risks of warfare than their paper-pushers.

The past was different.

I often find these threads a little optimistic - we want things to have been better for women in the past.
Can you see the men allowing women to choose the best of them?
Likely the most violent and aggressive subdued the weaker men then took the women as wives/mothers.
Meaning that aggressive male traits are propagated.
It makes sense from an evolution point of view and explains a lot about modern men.
Someone pointed out orangutans are matriarchal. I don't think they are, but bonobos are. However, chimps are patriarchal with one male fertilising most of the females.

The Byzantine Empire springs to mind ....

One thing I haven't seen mentioned (sorry if I haven't read carefully enough,) is that in modern polygamous societies men can have more than one wife because their wives are much younger (30 year old man marries 20 year old woman then marries another 20 year old aged 40 and then aged 50).
There are fewer 50 year old men in the population than there are 20 year old women.
So men don't always need to rape or capture women to have lots of wives - they just need to pick very young women and wait till the other men die.
They may also have lots of wives in succession (I'm sure some early modern women at least were afraid of pregnancy due to the risk of death).

Byzantium, Babylon, China, Assyria, Ethiopia, Korea, Egypt . . . . . .

It was so usual, and so efficient in achieving its ends, that I suspect it happened anywhere that society was complex enough to have an upper class that would find strong intelligent men with no dynastic ambitions useful.

I know, it’s a nice thought, but yes, probably over-optimistic.

I mentioned orangutans, and whilst they aren’t strictly matriarchal, the females live in overlapping territories, and the males are completely solitary and join the female ‘groups’ just long enough to breed.

Still a better social structure than our human patriarchy. I recall reading about a troop of baboons than became matriarchal after all the aggressive males died, so maybe there’s hope for us yet?

What’s it gonna be called and when is it out?!

Ahhh that would be telling just now. But the writing is going very well and I expect to have a first draft by Easter. Will update you once it’s ready!

Yes - and I think the Christian convention of monastic celibacy was a version of this. The church effectively operated (in several ways - care of the sick, education, administration of lands) as a state bureaucracy.

Evo-psych defenders of patriarchy often overlook how artificial it actually is, in terms of what we know about female sexuality. For obvious reasons, women are WAY more selective than men about who they go to bed with. But the more patriarchal a set-up, the less choice they have over their partners. Fully patriarchal societies hand women over as objects. Nothing in our biological evolution agrees with this. As such, I still have (some) hope.

Interesting thread, can this latecomer reboot it?
The early city states pre-date empires, with Sumer having been founded around 5000- 4000 bc and it’s generally thought that it was much more egalitarian in its earliest times. It became more patriarchal in later times. There are also the peculiar early large ‘cities’ of the Cucuteni of Europe which are also said to be more egalitarian, or even matriarchal.

Empires are generally only said to have been invented about 2400 BC, with Sargon. Perhaps it’s imperialism that is equated with patriarchy? It stands to reason, if imperialism is equated with that loved-by-males idea of might making right. Not that reason often has much to do with societies. The timing works in Sumeria.

In Britain the Anglo Saxons, certainly in Mercia? are also thought to have been more egalitarian between sexes, a trait that may have been quite common in north Europe looking at the Norse too. Anglo Saxon villages are quite famously egalitarian in economic terms, with the open field system. Equality between sexes is often linked to equality in other areas, and vice versa, it seems. Trouble came for women from the Normans, who basically replicated the adventures of the Roman Empire in Britain.

The Y-chromosome bottleneck emerged around 5,000 BC and continued for two thousand years. It was finally released by the growth of city-states such as Uruk around the Fertile Crescent, the Indus Valley and along the Yellow River.

The only credible explanation for that bottleneck is extreme inter-clan violence leading to domination by a limited number of male lines. Total patriarchy, in other words. It's very similar to what Yamnaya DNA did to Western Europe - just around the time the global bottleneck eased up.

It's not at all unlikely the Cucuteni-Trypillia settlements arose as a response to the patriarchal clan warfare raging all over Eurasia. The early ones are notable for their massive size and absence of any visible hierarchy. They also seem to have attempted strong defences, indicating that they expected raiders. Conurbations of many thousands would certainly have been less exposed than family-based farms and villages.

As the bottleneck continued, Cucuteni sites began to reflect more hierarchical cultures. It's really something that they seem to have lived in very large, egalitarian settlements for about a thousand years. We don't (yet) know how they pulled that off or what prompted them to start elevating central authorities.

However, they are not evidence of a nicer way of life existing before the rise of empire. They were almost certainly refuges from the vicious patriarchy rampaging all over the world.

Pre-bottleneck, Neolithic peoples may well have been more peaceful and egalitarian or, at least, many may have been until some clans got big enough to send out raiding parties. It's probably true that agricultural improvements afforded the luxury of warfare.

Afaik, we haven't enough British Western Hunter-Gatherer (Cheddar Man) DNA to know whether the Y-chromosome bottleneck afflicted them here. But it hardly matters, as they were wiped out by the Anatolian Neolithic Farmers who were then obliterated by the Yamnaya.

As you say, there are lots of different ways to colonise a nation. You can murder all the people, murder all the men, infiltrate the people and/or use oppressive systems to exploit the people while keeping your own DNA to yourselves. The Romans and the Normans pretty much did the latter in Britain, as the emerging Bronze Age empires did in their times.

The Old Testament tells us the early Hebrews went for the murder-based strategies, having started (according to the text) with their very own bottleneck of 12 male lines. Contemporaneous civilisations who left records of their rulers also glorified male entitlement by heritage and their destructions of other peoples.

It is truly bizarre that so much of human history - the force that shaped who we are, configured and reconfigured our landscapes, built and destroyed, learned and forgot - has been driven by the Y-chromosome's determination to be the only one. It's a pity, too, that history's been recorded mainly by dominant males. I'm sure this says something about patriarchal contempt for the female voice.

What a fascinating thread. I spend a lot of time pondering about the animal side of humanity and how it affects behaviour.
Am not as erudite as most on this thread but having come across popular science such as The Selfish Gene and The Mouse Paradise experiment I can’t help but apply to what I see around me.
On a societal/National/Ethnic level who are the successful groups currently? The ones who control their population through religion and culture to reproduce the most. Arranged marriages, lack of choice for women and early marriage. The West isn’t doing so well there.

Someone asked up thread about alternatives. Australia carried on as HG society for about 40000 years, til disease, rigid religion and patriarchy turned up in the form of colonialism.

South and Central America also has a fascinating history.

Little has been said here on the subject of mass disease and especially zoonotic infections that HGs didn't suffer. And climate change and extreme weather events causing famines, and perhaps giving rise to myths like Atlantis in Europe.

There are no infectious diseases that kill or sterilise only one sex.

On the South American continent, Spanish and Portuguese colonisers adopted a combination of strategies that included miscegenation - male settlers were, at times, incentivised to marry native women. While the reasoning was economic and religious, it's a relatively recent illustration of Y-chromosome intrusion as compared to replacement.

British colonisers of the Northern continent just went for replacement. All the Europeans adhered to patriarchy, though. While Southern miscegenation led to interesting genetic and cultural outcomes, they collectively succeeded in chasing out alternative social structures, leaving only small enclaves in the more remote areas.

Up in the far north of prehistoric Scotland, the Yamnaya reached where the Anatolians had not - the landscapes are better for livestock than horticulture. Some interesting things happened there. The Neolithic population of Skara Brae in the Orkneys was quickly replaced by female Yamnaya DNA , the original Y-chromosomes continuing unchanged. I can think of a few ways this may have happened (none of them good for the original women) but we'll probably never know for sure.

I haven't seen much material linking this development to climate change, but it is established that it coincided with rapid Northern European cooling and coastal erosion. Farming became much harder; there's skeletal evidence of widespread malnutrition. Darker-skinned people would've been more susceptible to Vitamin D deficiency. But none of this explains the DNA switch.

Frustratingly, we can't know whether these unusual mitochondrial replacements resulted in less patriarchal and/or more matriarchal societies! I mean, it could be that the invaders presented the dark-skinned Orcadian men with opportunities to lord it over these new women and promptly chucked their own wives & daughters out. Or the new women could've been a rebel faction, determined to set up female-led colonies far away from their bossy brothers.

One man reproduced for every 17 women! No matter what narrative we superimpose on this, it's quite an unpleasant picture. 17 women getting pregnant for each impregnator. Men indisputably took control over women and dictated which men they could reproduce with.

Jesus. 🤣 I've only skim read it and it seems pretty clear that 'reproduce' isn't referring to the act of sex/impregnation. It's talking about the survival of DNA.

It literally says:

What the Data Actually Means

• Genetic Lineages vs. Living People: It does not mean that 16 out of 17 men failed to have children or that harems of 17 women per man were the norm. 1, 2]
• The Y-Chromosome Bottleneck: Geneticists studying modern DNA tracked the Y chromosome (passed strictly from father to son) and compared it to mitochondrial DNA (passed from mothers). They found that only a tiny fraction of male ancestral lines successfully passed down genetic material that survived into the modern day.

Sounds more like women committed gendercide against men. A sort of DNA based ethnic cleansing.

This may have incidentally been what actually caused the patriarchy. The widespread eradication of male DNA leaving only a chosen few who became the patriarchs of today.

I wouldn't be surprised if there were a few matriarchs at the top, kicking it with the men and keeping all the other women down. The OG dick panderers. 🤣

I have only just realised that landed gentry means gentleman with land. Not that they landed on ships. You’ve just blown my mind.

Cyber-attack, not massed infantry, is coming to define warfare.

Well, that's the oft repeated claim but I'm not sure it's based in any real truth. We haven't really had any truly precarious wars since the invention of the internet - nobody seriously thought the Iraq war might end up with us all speaking Arabic.

You only have to look to Ukraine to see how a current day war is playing out. It's literally fighting in the streets and bomb strikes. And when the orange buffoon wants to threaten another country it's not usually a cyber attack he threatens.

Yes, that was my point.

Your reply about the meaning of the 1:17 ratio's irrelevant. No-one here thinks there was some kind of structured distribution of women. What it does mean is that the men of a few successful tribes killed or otherwise neutralised the men of all other tribes.

Nearly 95% of male genetic lineages were effectively eliminated or lost from the gene pool.

As soon as that bottleneck began to release, Yamnaya-descended pastoralists eliminated or replaced 60% to 100% of the native male Y-chromosome lineages in Western Europe, depending on region.

Could it not also have been disease related or caused by inbreeding/birth defects etc?