Re: The taxonomy of Sahelanthropus tchadensis from a craniometric perspective

On 8/5/24 12:00 PM, Mario Petrinovic wrote:

On 5.8.2024. 15:28, John Harshman wrote:

On 8/5/24 2:52 AM, Mario Petrinovic wrote:

On 5.8.2024. 6:40, John Harshman wrote:

On 8/4/24 8:48 PM, Mario Petrinovic wrote:

On 4.8.2024. 20:50, John Harshman wrote:

Don't be shy. Just say what you mean. Preferably in a single post.

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         While we are at that, I will not be shy and I will ask you a question I always wanted to clear it up.
         You have two situations. In Africa you have a lot of separated small tribes, so high genetic diversity. In India you have all humans connected in one big society, so genes exchange among the whole population, and they average over time, so we have low genetic diversity. Now, the question is, in the view of geneticists is India the bottleneck?

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If you just waited a while before posting and thought more about what you wanted to say, you wouldn't have this problem. Consider that.
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Meanwhile, I don't understand the question. India is not a bottleneck. What bottleneck? And you misunderstand the nature of African genetic diversity. Most of it is within populations, not between them. Africa has much higher within-population diversity than does the rest of the world.

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         India - This is from Wikipedia: "A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as genocide, speciocide, widespread violence or intentional culling. Such events can reduce the variation in the gene pool of a population; thereafter, a smaller population, with a smaller genetic diversity, remains to pass on genes to future generations of offspring. Genetic diversity remains lower, increasing only when..." So, they say that India is a bottleneck, it is not me that is saying this, I know that India isn't a bottleneck.

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Who says that India is a bottleneck? All you have shown here is a definition of the term. And that definition doesn't even apply to India. You may be trying to say that India experienced a bottleneck many years ago, but even that just isn't true.

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         The definition implies less diversity for less prosperous situation. I would say that India has more prosperous situation than Africa.

 The definition implies no such thing. A bottleneck is a population reduction to near zero. All your quote does is give some of the possible reasons for that reduction. The population of India is huge and has been for a very long time. No bottleneck. The reasons why Africa has more genetic diversity than the rest of the world (not just India) are likely to be that a small sub-population of modern humans left Africa and rapidly expanded. Rapid expansion doesn't create genetic variation, which remains at the level of the founder population for a long time.
 

         Look, I am a retired train driver (who excellently understood simple mathematics when he was kid), I do understand that in homogeneous population genes average. How come scientists have a complete lack of understanding of this, and why their logic is so simple that even kids in kindergarten would be ashamed of it, is beyond me. In other words, when humans are the most advanced, when they have multiple trading connections, when they all live *as one*, then they have the least genetic variation. In other words, what in real life is the most prosperous situation scientists describe as the least prosperous situation. In the most prosperous situation humans advance, which is only logical. But scientists postulate that in the least prosperous situation humans advance. How come? There is few people, and then comes God and does his magic, and that magic advances those few.

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Maybe scientists understand something you don't. Maybe your understanding here is just wrong. You are confusing a lack of geographically structured variation with a lack of individual variation. Do you even read what I say?

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         I read what you say, if this is the right meaning for what I am doing, don't worry about it.

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         Africa - Yes, of course, this is how variation emerges, you receive influxes from outside, and those influxes create genetic diversity.

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That has almost nothing to do with the variation within Africa.
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In a homogeneous population, without outside influxes, Actually, if those outside influxes are very small compared to your big size, you cannot have diversity. So, In Africa you have multiple (because they are separated) sources of genes, which receive, from time to time, influxes from other separated sources.
         In other words, more separation, more genetic diversity, less separation, less genetic diversity. More separation equals less prosperous world, less separation equals prosperous world, just like we have today. Scientists turned everything upside down, and there isn't a single one among them who understands this.
         So, to have genetic variation you got to have a lot of similar sizes separated gene pools. If you have a single gene pool there is no variation.

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This is just nonsense.