Same caste ollani enduku pelli cheskokudadu

[Jombo0108]

Puuu

[Scada]

Suu

[Jombo0108]

http://www.andhrafriends.com/topic/765481-precautions-before-marriage/#comments

[DummyVariable]

1 hour ago, Jombo0108 said:

http://www.andhrafriends.com/topic/765481-precautions-before-marriage/#comments

 

Vuu

[BetaCat]

2 hours ago, DummyVariable said:

Let us say a random caste has about 3% of the population of AP, i.e. 1.2 million people are marrying among themselves. That is a large population in my view. So the genetic diversity should already be there regardless of the smaller source. There may be more choice with larger pool of genes but it doesn’t mean that 1.2 million people are lacking diversity. In fact, if genetic effects were so severe, the population will not even be this large in the first place. Let us not mix same caste marriages with incest. Those are two different concepts and one will eventually lead to greater genetic diversity while the other one will not.

If the people are 1.2 million in 2019, with the population growth curve we have, when castes were formed, the number of people who were founders for these 1.2 million were probably a few thousand. Few thousand people have inbred and formed a few million people over generations. You see where the problem is?

[DummyVariable]

1 minute ago, BetaCat said:

If the people are 1.2 million in 2019, with the population growth curve we have, when castes were formed, the number of people who were founders for these 1.2 million were probably a few thousand. Few thousand people have inbred and formed a few million people over generations. You see where the problem is?

The point is genetic diversity will eventually come in large populations even though they started of small and had little diversity to begin with.

[BetaCat]

10 minutes ago, DummyVariable said:

The point is genetic diversity will eventually come in large populations even though they started of small and had little diversity to begin with.

Where will the diversity come from? Who taught you genetics? Every gene will have a repressive allele or a dominant allele. For a given population of people, the ratio of repressive to dominant for all genes will not be at 50:50. Now let's say a particular gene is found at 70:30 repressive to dominant. Now, as you procreate from 1000 to 10^6 (1000-fold increase), the likelihood of that particular gene being repressive will reach over 90% if you inbreed. We only have four chances of getting any of our genes, TT, Tt, tT and tt. So we are restricted by probability if we inbreed. 

[DummyVariable]

3 minutes ago, BetaCat said:

Where will the diversity come from? Who taught you genetics? Every gene will have a repressive allele or a dominant allele. For a given population of people, the ratio of repressive to dominant for all genes will not be at 50:50. Now let's say a particular gene is found at 70:30 repressive to dominant. Now, as you procreate from 1000 to 10^6 (1000-fold increase), the likelihood of that particular gene being repressive will reach over 90% if you inbreed. We only have four chances of getting any of our genes, TT, Tt, tT and tt. So we are restricted by probability if we inbreed. 

If there are large populations that itself means that it is not inbreeding. How is different families mingling together inbreeding? Same thing happens in the wild and there is genetic diversity there. Suggesting that it would not happen with humans is a bit misleading.

[BetaCat]

2 minutes ago, DummyVariable said:

If there are large populations that itself means that it is not inbreeding. How is different families mingling together inbreeding? Same thing happens in the wild and there is genetic diversity there. Suggesting that it would not happen with humans is a bit misleading.

You're talking about 1000 fold increase in population. Let's say two people are related and give birth to a child, that's inbreeding but that's only 1-fold increase in population. Here you're talking about 1000-fold increase in population. Even distant people not necessarily related by blood, share genes, only at a lesser frequency. But if the population growth is exponential and you see a 1000 fold increase, the repressive allele reach a frequency of over 90%. If the same thing happens in blood relationship, you don't need a 1000-fold increase in population to see the effects of repressive genes, you see it much earlier. 

[BetaCat]

Also in the wild, Inbreeding avoidance occurs in nature by at least four mechanisms: kin recognition, dispersal, extra-pair/extra-group copulations, and delayed maturation/reproductive suppression. You should study evolutionary biology, it's very interesting. Animals use olfaction as one way to avoid inbreeding, they smell their kins. 

[DummyVariable]

7 minutes ago, BetaCat said:

You're talking about 1000 fold increase in population. Let's say two people are related and give birth to a child, that's inbreeding but that's only 1-fold increase in population. Here you're talking about 1000-fold increase in population. Even distant people not necessarily related by blood, share genes, only at a lesser frequency. But if the population growth is exponential and you see a 1000 fold increase, the repressive allele reach a frequency of over 90%. If the same thing happens in blood relationship, you don't need a 1000-fold increase in population to see the effects of repressive genes, you see it much earlier. 

Firstly, caste populations were never small to begin with in India. Until the Gupta period, there were hardly any divisions. So the starting population was much larger. So when 1000s of families form a caste, multiply and become millions, why can’t genetic diversity be not present?

[BetaCat]

8 minutes ago, DummyVariable said:

Firstly, caste populations were never small to begin with in India. Until the Gupta period, there were hardly any divisions. So the starting population was much larger. So when 1000s of families form a caste, multiply and become millions, why can’t genetic diversity be not present?

Are you stupid our you choose to not understand what I just said? Do you know how the gene of a progeny is formed? If both mother and father have a dominant genes, the likelihood of the child having the dominant gene is 100%. If one has a dominant and one has a supressive gene, the likelihood of the dominant gene is 25% homo and 50% hetero which means that there is a 75% chance that the suppressive gene is lost....some genes extinguish as you move forward in generations. This is for one progeny. For a thousand fold increase in population the likelihood of finding the supressive gene is (0.25)^1000. Now even if you have started with 1000 people or 10,000 people, if there is a 1000-fold increase in population, the same math applies. 

[DummyVariable]

17 minutes ago, BetaCat said:

Are you stupid our you choose to not understand what I just said? Do you know how the gene of a progeny is formed? If both mother and father have a dominant genes, the likelihood of the child having the dominant gene is 100%. If one has a dominant and one has a supressive gene, the likelihood of the dominant gene is 25% homo and 50% hetero which means that there is a 75% chance that the suppressive gene is lost....some genes extinguish as you move forward in generations. This is for one progeny. For a thousand fold increase in population the likelihood of finding the supressive gene is (0.25)^1000. Now even if you have started with 1000 people or 10,000 people, if there is a 1000-fold increase in population, the same math applies. 

1000s of families does not equal 1000 individuals. Secondly, the starting group itself was diverse. So that diverse group, sufficiently large already, multiplied and became a million. What you are saying literally means that people marrying in the same city like providence, RI are inbred. It is just your assumption that initial populations were small and inbred. They never were. They are not inbreeding now either unless they married within their own family, which is also not happening.

[BetaCat]

20 minutes ago, DummyVariable said:

1000s of families does not equal 1000 individuals. Secondly, the starting group itself was diverse. So that diverse group, sufficiently large already, multiplied and became a million. What you are saying literally means that people marrying in the same city are inbred. It is just your assumption that initial populations were small and inbred. They never were. They are not inbreeding now either unless they married within their own family, which is also not happening.

Ok, you need to look up what founder effect is...if the progeny is created only from a select group of population, it will result in loss of alleles if you're breeding amongst that subgroup, it's only the question of how many generations. As a result, after every generation the gene distribution changes. See image below. 

So if you start with this, you will get this. 

 

Read more about founder effect. 

[BetaCat]

The founder effect is a loss of genetic diversity that happens when a small population is separated from a larger gene pool. Because the smaller population has less genetic diversity, they are more likely to be genotypically and phenotypically unique from the original population. The founder effect can also lead to speciation.