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One statement in there grates: the idea that there never was a big population drop before. We know it from genetic records that human population dropped to a v

by polotics 11mo ago

One statement in there grates: the idea that there never was a big population drop before. We know it from genetic records that human population dropped to a very low number. The human population bottleneck around 70,000 years ago, ie Toba supervolcano eruption, with 1,000 to 10,000 breeding individuals. There may have been other humans around, their lines all died out.

igor47 11mo ago
From TFA: > Because Homo sapiens went through a series of near extinction level events before eventually triumphing – periodically reduced to a few thousand surviving members clinging on in a handful of African enclaves – we have very little genetic variation. The human family tree spreads out from a few individuals to encompass all of us.
- Bombthecat 11mo ago
  And yet, we are still here and will still be here, even if we get reduced to a few thousand again
squigz 11mo ago
How do we know there was only 1,000-10,000 individuals, 70,000 years ago?
- az09mugen 11mo ago
  I was wondering the same question, and IIRC it's due to the DNA diversity we have today. This is roughly calculated with the successive generations of humans and accounting possible mutations.
  - squigz 11mo ago
    If this is the case, how can we know whether that number represents a drop in population or not? Can we measure population size 100,000 years ago? 50,000? Then compare them? What about that number represented as % of total population? 1,000-10,000 sounds low, but our population probably wasn't very high that long ago either.
    - recursivecaveat 11mo ago
      Hypothetically if you took a random sample of present humans you would have a low # of say skin tones in wide range, whereas a small isolated and stable population should have a low # of low variety. So you can tell by that kind of difference whether it was a sudden drop or more of a sustained thing. Presumably in a more sophisticated statistical way across a wide variety of genes of course. Apparently there is another bottleneck ~900K years ago that has decent fossil record support but the Toba one is more disputed.
jack_tripper 11mo ago
>One statement in there grates: the idea that there never was a big population drop before Nobody actually thinks there was never a population drop. The issue is there never was an economic, pension and welfare system built on population growth, so that when populations did dip, nobody was affected by the dip. But on the contrary, in the past of agrarian societies, population declines massively benefited the working class, as they had more bargaining power with the landlords. This doesn't work in the economies and societies of today when your retirement depends on there being constant economic and population growth.
wolvesechoes 11mo ago
Problem is not shrinking population. Problem is shrinking population with shrinking share of children and young adults and growing share of old people in the time when most people are completely helpless without access to modern goods and services.

igor47 11mo ago

From TFA: > Because Homo sapiens went through a series of near extinction level events before eventually triumphing – periodically reduced to a few thousand surviving members clinging on in a handful of African enclaves – we have very little genetic variation. The human family tree spreads out from a few individuals to encompass all of us.

Bombthecat 11mo ago
And yet, we are still here and will still be here, even if we get reduced to a few thousand again

squigz 11mo ago

How do we know there was only 1,000-10,000 individuals, 70,000 years ago?

az09mugen 11mo ago
I was wondering the same question, and IIRC it's due to the DNA diversity we have today. This is roughly calculated with the successive generations of humans and accounting possible mutations.
- squigz 11mo ago
  If this is the case, how can we know whether that number represents a drop in population or not? Can we measure population size 100,000 years ago? 50,000? Then compare them? What about that number represented as % of total population? 1,000-10,000 sounds low, but our population probably wasn't very high that long ago either.
  - recursivecaveat 11mo ago
    Hypothetically if you took a random sample of present humans you would have a low # of say skin tones in wide range, whereas a small isolated and stable population should have a low # of low variety. So you can tell by that kind of difference whether it was a sudden drop or more of a sustained thing. Presumably in a more sophisticated statistical way across a wide variety of genes of course. Apparently there is another bottleneck ~900K years ago that has decent fossil record support but the Toba one is more disputed.

jack_tripper 11mo ago

>One statement in there grates: the idea that there never was a big population drop before Nobody actually thinks there was never a population drop. The issue is there never was an economic, pension and welfare system built on population growth, so that when populations did dip, nobody was affected by the dip. But on the contrary, in the past of agrarian societies, population declines massively benefited the working class, as they had more bargaining power with the landlords. This doesn't work in the economies and societies of today when your retirement depends on there being constant economic and population growth.

wolvesechoes 11mo ago

Problem is not shrinking population. Problem is shrinking population with shrinking share of children and young adults and growing share of old people in the time when most people are completely helpless without access to modern goods and services.