4 ms·

Interesting article, but it's missing the true dynamics. One of the interesting things in the past few years we've seen is evolution and population dynamics on

Interesting article, but it's missing the true dynamics. One of the interesting things in the past few years we've seen is evolution and population dynamics on a very fast and very relevant scale with COVID. You'd see case numbers going up and down, but since mid 2021 or so, the main thing driving rates was the reproduction number of the most contagious variant in existence. At times you'd see the overall case counts going down, but one particular variant growing quickly, and you would know that very soon the number was going to go up again. The dynamics of viral and human populations are not so different. Groups that have a reproduction number less than 1 (same as TFR<2) will die out. Those that have a reproduction number greater than 1 will grow and come to take over. Right now, the populations that have R>1 are largely in Africa. That said there are little pockets in R<1 countries that are R>1. In the U.S. for example you see groups like the Amish and the Mormons. As long as there's enough food and no wars or mass oppression, groups with R>1 will eventually constitute effectively the entire population. Now, of course, humans are more complicated than viruses. Viruses don't have beliefs or values that can be transmitted to the next generation, just genes. For this to work for humans, the humans have to pass along their pro-kid value system to the next generation. Some groups will do this, and some won't, but the world is big enough that there will be groups that do manage to do this, and they will inherit the Earth.

somedude895 3y ago
> Groups that have a reproduction number less than 1 (same as TFR<2) will die out. But will they really? Fertility rates are hard to predict and I feel like at a certain point a society might deurbanize with people moving to the countryside and have more children again. Maybe it's at 100 million, maybe at 10 million population, but I just can't fathom a 100 million society just going to zero or even the hundreds of thousands. Maybe I don't understand the dynamics.
- Ygg2 3y ago
  > society might deurbanize with people moving to the countryside and have more children again. That's not what is happening. Ask yourself is it more likely a young girl is going to the city or to the countryside? Once you run out of fertile females your fertility rate is 0.
  - somedude895 3y ago
    > Ask yourself is it more likely a young girl is going to the city or to the countryside? At this point that is quite unlikely but still >0. But I also think the argument is quite myopic. There's a definite mental health crisis among young people and especially women, which could possibly be attributed to the lack of purpose that is a consequence of modern life, so a countermovement in at least part of a population is not unthinkable. And that's just one possible thing that could trigger such a shift.
jltsiren 3y ago
Historically, cities usually had R < 1. Cities were unhealthy places, and the urban poor had fewer opportunities to provide for their children than the rural poor. Regardless, people continued to migrate to cities for economic opportunities, and cities were the places where social and cultural developments happened. Parents passing their values to their children does not seem to be the right model. Children choosing from the available opportunities is a bit better. Groups with high fertility rates tend to export people, because there is not enough room for the excess children in their ancestral culture. The ones who leave tend to be the ones who did not fit into the culture anyway, and they often adopt new values and a new way of life.
WJW 3y ago
This line of thinking is common but highly flawed. If it were true, everyone would be super religious just because their ancestors were. In reality there are several issues: - People have minds of their own and can willingly choose to leave a group. You see this all the time with Mormons for example. In order for such a group to eventually dominate, they need to grow even faster to compensate for this natural "leakage". - "As long as there's enough food and no wars or mass oppression" seems like an extremely optimistic assumption. - Reproduction rate is not constant. It is quite possible that R will be low for a couple of decades or centuries before rising again (and possibly falling again even later). Trying to predict long term trends by linearly extrapolating the current value of such a highly variable metric is not going to work in any complex system.
- pantalaimon 3y ago
  That requires ideas to be easily transmissible. You absolutely have regimes and cults that work hard to shield their members from being "infected" by outside ideas by instilling that those are a heresy and ultimately the source of bad things.
- lotsofpulp 3y ago
  > This line of thinking is common but highly flawed. If it were true, everyone would be super religious just because their ancestors were. Most people of the world did not have access to super effective birth control until recent decades. And most women did not have complete agency until recent decades.
sparrowInHand 3y ago
Case in point: Israel?
lynx23 3y ago
Ahhh, you apparently listened to Agent Smith :-)
Thoeu388 3y ago
[flagged]
seydor 3y ago
Darwinist arguments are wildly off. At any point in history the dominant cultural group was a minority, as is today

somedude895 3y ago

> Groups that have a reproduction number less than 1 (same as TFR<2) will die out. But will they really? Fertility rates are hard to predict and I feel like at a certain point a society might deurbanize with people moving to the countryside and have more children again. Maybe it's at 100 million, maybe at 10 million population, but I just can't fathom a 100 million society just going to zero or even the hundreds of thousands. Maybe I don't understand the dynamics.

Ygg2 3y ago
> society might deurbanize with people moving to the countryside and have more children again. That's not what is happening. Ask yourself is it more likely a young girl is going to the city or to the countryside? Once you run out of fertile females your fertility rate is 0.
- somedude895 3y ago
  > Ask yourself is it more likely a young girl is going to the city or to the countryside? At this point that is quite unlikely but still >0. But I also think the argument is quite myopic. There's a definite mental health crisis among young people and especially women, which could possibly be attributed to the lack of purpose that is a consequence of modern life, so a countermovement in at least part of a population is not unthinkable. And that's just one possible thing that could trigger such a shift.

jltsiren 3y ago

Historically, cities usually had R < 1. Cities were unhealthy places, and the urban poor had fewer opportunities to provide for their children than the rural poor. Regardless, people continued to migrate to cities for economic opportunities, and cities were the places where social and cultural developments happened. Parents passing their values to their children does not seem to be the right model. Children choosing from the available opportunities is a bit better. Groups with high fertility rates tend to export people, because there is not enough room for the excess children in their ancestral culture. The ones who leave tend to be the ones who did not fit into the culture anyway, and they often adopt new values and a new way of life.

WJW 3y ago

This line of thinking is common but highly flawed. If it were true, everyone would be super religious just because their ancestors were. In reality there are several issues: - People have minds of their own and can willingly choose to leave a group. You see this all the time with Mormons for example. In order for such a group to eventually dominate, they need to grow even faster to compensate for this natural "leakage". - "As long as there's enough food and no wars or mass oppression" seems like an extremely optimistic assumption. - Reproduction rate is not constant. It is quite possible that R will be low for a couple of decades or centuries before rising again (and possibly falling again even later). Trying to predict long term trends by linearly extrapolating the current value of such a highly variable metric is not going to work in any complex system.

pantalaimon 3y ago
That requires ideas to be easily transmissible. You absolutely have regimes and cults that work hard to shield their members from being "infected" by outside ideas by instilling that those are a heresy and ultimately the source of bad things.
lotsofpulp 3y ago
> This line of thinking is common but highly flawed. If it were true, everyone would be super religious just because their ancestors were. Most people of the world did not have access to super effective birth control until recent decades. And most women did not have complete agency until recent decades.

sparrowInHand 3y ago

Case in point: Israel?

lynx23 3y ago

Ahhh, you apparently listened to Agent Smith :-)

Thoeu388 3y ago

[flagged]

seydor 3y ago

Darwinist arguments are wildly off. At any point in history the dominant cultural group was a minority, as is today