Why Do Genes Suggest Most Men Died Off 7,000 Years Ago?

Live Science ^ | June 6, 2018 | Yasemin Saplakoglu

[SunkenCiv]

Modern men's genes suggest that something peculiar happened 5,000 to 7,000 years ago: Most of the male population across Asia, Europe and Africa seems to have died off, leaving behind just one man for every 17 women.

This so-called population "bottleneck" was first proposed in 2015, and since then, researchers have been trying to figure out what could've caused it. One hypothesis held that the drop-off in the male population occurred due to ecological or climatic factors that mainly affected male offspring, while another idea suggested that the die-off happened because some males had more power in society, and thus produced more children.

Now, a new paper, published May 25 in the journal Nature Communications, offers yet another explanation: People living in patrilineal clans (consisting of males from the same descent) might have fought with each other, wiping out entire male lineages at a time.

That ratio of 17 females for every one male "struck us as being very extreme, and there must be another explanation," said senior study author Marcus Feldman, a population geneticist at Stanford University in California. According to their new explanation, the male population didn't take a nosedive, but rather the diversity of the Y chromosome decreased due to the way people lived and fought with each other. In other words, there weren't actually fewer males, just less diversity among the males.

[SunkenCiv]

This has to do with larger family sizes due to the rather sudden shift to agriculture, and the fact that polygamy is the most common practice among primates.

[Paladin2]

FemiNazis 0.0

[jim_trent]

I think it is because that was when the first decent beer became available and the words “Hold my beer and watch this” were first used.

[Gamecock]

Most of the male population across Asia, Europe and Africa seems to have died off, leaving behind just one man for every 17 women.

Which is one of those things that briefs well, until you actually have to put up with 17 woman.

<DuckingForCover>

[SunkenCiv]

Besides larger family sizes, and polygamy, better diets led to lower infant mortality. Anyone who has done genealogy finds both huge family sizes (often finding a single family more than once, depending on how many generations one looks back) as well as perilously narrow family lines (no first cousins, parent with no first cousins, grandparent on same line with no first cousins).

And, in my best heads I win tails you lose fashion, even if there were no change in infant mortality, polygamy would drive up the survival -- and hence lower genetic diversity among descendants -- of the the early farmer dad's double helix.

[E. Pluribus Unum]

World War I pretty much wiped out the men of native families in Great Britain. Entire towns lost all their men.

http://www.dailymail.co.uk/news/article-3927026/Tragedy-lost-generation-Map-shows-towns-cities-WWI-wiped-tens-thousands-people-including-circles-friends-Britain-left-scarred-forever.html

[babble-on]

Stands to reason that as migratory bands gave way to cities, and wars became the norm, that the protection that a king could offer to women would be worth a lot. Attack the neigboring city, kill all the males, bring the women back, repeat.

How many “wives” did King Solomon have?

Monogamy is a far more stable structure, because the incentive to kill the king is so much lower if everyone has a chance to pair up, but clearly there were other phases.

[donna]

The Biblical data places the Flood at 2304 BC ± 11 years.

[central_va]

Dr. Strangelove, call on line one.

[SunkenCiv]

Seems like hunting-gathering would have caught on again. ;^)

[Two Kids' Dad]

One man for every 17 women is every man’s dream... or every man’s nightmare if their menstrual cycles are aligned.

{{{ducking}}}

[M Kehoe]

“Most of the male population across Asia, Europe and Africa seems to have died off, “

Maybe the Lord didn’t like that model?

Sorry.

5.56mm

[freedumb2003]

>>I think it is because that was when the first decent beer became available and the words “Hold my beer and watch this” were first used.<<

THREAD WINNER!!!

[Bonemaker]

Theres only one whitetail buck per how many does?

[Pravious]

My ex-wife invented a time machine, and they all died trying to escape her.

[SunkenCiv]

If they’d all been models, the men wouldn’t have had 17 of ‘em.

[Hischild]

Well, the Biblical account says only the male line of Noah survived the flood. The wives of Noah and his sons were probably all of different lineage. One male line, multiple female lines. Something to think about.

[Bonemaker]

“Most of the male population across Asia, Europe and Africa seems to have died off, leaving behind just one man for every 17 women.”

That’s terrifying...poor bastard! A 1:1 ratio scares me and I’m fearless.

[Carriage Hill]

+1.

[BlackAdderess]

Isn’t it obvious? Whenever you have wealthy powerful men collecting multiple women because they can afford to do so, you have wealthy powerful men figuring out ways to get rid of the other men, particularly the younger ones.