Europeans Without Crowd Disease Exposure Died, Those Without Genetic Resistance Died 10x More?

Just to confirm, while isolated European/Eurasian populations without crowd disease exposure did die at "above normal rates" when first exposed to it (viz, the Faroese measles epidemic) peoples without genetic resistance died about 10 times more, holding other factors constant. This is roughly correct, right?
 
As far as I know disease resistance is mostly not genetic, with some exceptions like malaria.
 
As far as I know disease resistance is mostly not genetic, with some exceptions like malaria.
While disease resistance is complicated - I suggest you check out the kurzgesagt YouTube video on the immune system - an important part does include hereditary immune reactions.
This explains why populations with a history of a particular disease will be less susceptible than those without. And why rapidly evolving diseases such as flu are such a worry.
I don't know the exact numbers though in order to answer the OP.
 
There is a difference between inherited adaptive responses and inherent genetic resistance. Progressive is specifically talking about genetic resistance.
 
There is a difference between inherited adaptive responses and inherent genetic resistance. Progressive is specifically talking about genetic resistance.
Is he though? Immunity comes from 3 sources: innate immune system, adaptive response, and natural biochemistry. The first and the last are both directly inheritable and both have been referred to as genetic resistance.
For example the inherited mutation that changes blood cells to be more resistant to malaria parasites is not part of the immune system.
 
As far as I know, there is really not much at all difference between populations on the first or the last, with exception of stuff like malaria resistance which probably falls under biochemistry.

And Progressive specifically mentioned that populations without exposure suffer higher mortality, and he's not talking about that. This leaves inherent, genetic immunity which is rare.

EDIT

Obviously, we are talking about much higher mortalities: if population A is genetically resistant or flat-out immune then they are going to suffer negligible deaths, so if population B suffers even something like 5% mortality it can easily be 10 times the one suffered by population A.
 
Last edited:

BlondieBC

Banned
As far as I know, there is really not much at all difference between populations on the first or the last, with exception of stuff like malaria resistance which probably falls under biochemistry.

And Progressive specifically mentioned that populations without exposure suffer higher mortality, and he's not talking about that. This leaves inherent, genetic immunity which is rare.

EDIT

Obviously, we are talking about much higher mortalities: if population A is genetically resistant or flat-out immune then they are going to suffer negligible deaths, so if population B suffers even something like 5% mortality it can easily be 10 times the one suffered by population A.

There is a huge difference. Lets start with the basics. For genes that help the immune system, you want lots of types with lots of diversity. This makes it much harder on the germs. So in the human immune system, we see some of the greatest diversity of all our genes, and this is responding to genetic pressure. These genes all have at least 10 major variations, and most have hundreds of variations. On some of these genes, humans have 30 million old copies. Some living humans have parts of their immune system that are closer to Great Apes than other humans. HUGE selective pressure here.

Now lets talk about isolated populations, of which the Native Americans are the best known. They left Africa with the same genetic pool as the Europeans. But then these people spent many thousands of years slowly moving across Siberia, Frozen East Asia, Beringia, and finally into the Americas. At this time due to low population densities, parasites are the cause of most disease, not infectious disease. Most/All of these parasites are lost over this slow process because of poor adaptation to cold climates (malaria, and every other parasite which has a phase outside of humans) and even lower population densities. So we get this largely parasite free population in Alaska.

Then another effect sets in. Many of these parasitic worms suppress the immune system. So does TB. Without this suppression, auto immune disease become worse. So we now have 20,000 years selective pressure for a weaker immune system. This can be see in a lot of ways. Before I mentioned how an European valley might have hundreds of different type of genes at one gene location. American Indian villages could be 50% one type of gene. American Indians often have fewer autoimmune diseases such as Type I diabetes. American Indians also have the less efficient immune response to dealing with TB.

So then the Europeans come over. The disease run rampant, and keep the population down. You can look at the Central Mexico population records to see the data. Then as we have mixing of genes and continued selection pressure, we see the immune systems slowly improve. And then the rapid rise of the population. Even low single digit % of gene mixture can dominate specific parts of our DNA if matched with heavy selection pressure.

Now I am summarizing what in fairness would take hours to cover in any reasonable amount of detail. But it is clear that these isolated population have inferior genes when faced with the modern urban diseases.
 

BlondieBC

Banned
Just to confirm, while isolated European/Eurasian populations without crowd disease exposure did die at "above normal rates" when first exposed to it (viz, the Faroese measles epidemic) peoples without genetic resistance died about 10 times more, holding other factors constant. This is roughly correct, right?

I can just give you some data that comes to mind.

  • Europeans would die at a rate of 25% per year in the worst Malaria areas in Africa.
  • We have two big epidemics that hit Mexico. They were after Cortez. Scientist argue about what disease it was, but the first one had about a 50% reduction in population. You should probably compare that to life time morality from small pox or measles in Spain or any other European country. The second one was another 50% to 90%.
  • In the modern medicine era, we have seen death rates as high as 600 of 800. The example that comes to mind is TB. TB is mostly a chronic disease in urban world with a billion or two people carrying this bacteria. Most with no symptoms.

So I don't think you can get a simple ratio. The TB example probably gives me a 1000-to-1 increase in death rates. I suspect if I compare small pox to the great Mexican die offs, it can't be much above 4-to-1. In the last century of small pox, it killed 400 million people, so I suspect that in Spain in the colonial era it had to kill at least 5% of all people, mostly infants at their first exposure.
 
Back in this thread in August 2017, Intransigent Southerner advanced an argument that biological differences (in MHC, etc.) experienced by Native American ancestors through Siberia didn't matter for mortality (https://www.alternatehistory.com/fo...ases-they-brought.423964/page-2#post-15437850).

Or in other words isolated groups who diverged late from Eurasia without the bottlenecks found in Native American ancestors (in this case Polynesians who have most of ancestry from a Austronesian expansion around southern China 5000-2000BC) didn't have a mortality advantage upon encountering later Eurasian diseases.

May be worth a readover.
 

BlondieBC

Banned
Look at the picture below. Notice how the big die offs were not from the initial conquest. And more importantly, notice how the population does not recover for centuries. In an environment of abundant food, populations will grow 10-to-1 per century. Lack of genetic immunity is suppressing the long term recovery. So looking below, it looks like about 300 years until there is enough gene mixing to allow the population to begin a rapid recovery.

Mexico Central.jpg
 
I'm not entirely convinced that the end of colonial period has no correlation with the beginning of the rapid recovery. Certainly Spaniards using the natives as disposable slaves in the beginning contributed to the population collapse, or at least retarded recovery.

EDIT

I'm not saying genetics is not a significant factor, but I wonder how much of the population loss is _directly_ attributable to genetics and not environmental factors or secondary effects of extreme epidemics. European diseased could and _did_ kill a lot of Europeans too when they lived in terrible conditions.

EDIT 2

That 8 million dead is not enormously worse than European smallpox epidemics, 30% dead was pretty typical.
 
Last edited:

BlondieBC

Banned
I'm not entirely convinced that the end of colonial period has no correlation with the beginning of the rapid recovery. Certainly Spaniards using the natives as disposable slaves in the beginning contributed to the population collapse, or at least retarded recovery.

EDIT

I'm not saying genetics is not a significant factor, but I wonder how much of the population loss is _directly_ attributable to genetics and not environmental factors or secondary effects of extreme epidemics. European diseased could and _did_ kill a lot of Europeans too when they lived in terrible conditions.

EDIT 2

That 8 million dead is not enormously worse than European smallpox epidemics, 30% dead was pretty typical.

But the European population quickly recovered. Sure if we see a drop, then a rapid recovery over a generation or less, the North Americans have the same resistance as the Europeans. But this is not what the graph shows.

As to not being the main factor. Think on this. Brazil made contact with a isolated Tribe in the 1970's. Being fully aware of the death from disease issue AND with full modern medical technology, more than 600 of 800 died in the first year. MORE THAN 75% DEATH RATE EVEN WITH MODERN MEDICINE. So, if the modern EU made contact with 1480 Aztecs, we would still see a 90% population suppression. And most of the deaths were due to TB, a chronic disease.

And it is not uniquely pro-Northern European. It was not uncommon to have 75% death rates when modern Europeans explored Africa in the 1880's.

Now the genetics are due to the environment, and 20K years of evolution. One can focus on the deaths between 1500 and 1800. Or one could focus on the relatively disease free 20,000 years that preceded Cortes. Evolution is a harsh, uncaring mistress.
 
Top