Human Height

[kds1980]

Kanwardeep Singh ji

Above is not my understanding of genetic research on height for the past 35 years or more. In the 1970's when I was taking my graduate degree we were responsible for understanding the role played by genetics and environment in shaping human development. Studies of Japanese immigrants over 4 generations to Hawaii and California demonstrated a pattern of increasing height until in the last generation studied a plateau was reached and there was no further increase in height. Similar studies of the Dutch confirmed this.

Modern genetics demonstrates that many physical characteristics, including height, fluctuate within a range. A bottom average and a top average for any genetic pool. Thus you can see over generations some variation in average height. Whether a group's average falls to the bottom measure, or rises to the upper level, is explained by environmental factors such as nutrition.

Do you want references for this? I would be glad to provide them.

Though I agree what you said but still there are some flaws in it.Its better if some reasearchers will extend their study to countries like India which has several caste's and communitties are living side by side from hundreds of years.Yet one community is tall and other is short.For example jatts,Gujjars are tallest in North India and Bania are short.Both lived by side by side from hundreds of years.One cannot say that nutrition is poor among bani'as because they are quite rich.Diet of these communities is also same.So despite living side by side why Bani'as are short and jatt's are tall?

 

[spnadmin]

Though I agree what you said but still there are some flaws in it.Its better if some reasearchers will extend their study to countries like India which has several caste's and communitties are living side by side from hundreds of years.Yet one community is tall and other is short.For example jatts,Gujjars are tallest in North India and Bania are short.Both lived by side by side from hundreds of years.One cannot say that nutrition is poor among bani'as because they are quite rich.Diet of these communities is also same.So despite living side by side why Bani'as are short and jatt's are tall?

I thought I had explained that. It is neither genes nor diet alone that explains height averages for individuals from the same gene pool, but the combination of both. When nutrition is better for a group as a whole, then the individual height will be more likely to approximate the ceiling, or highest number, for that genetic pool or group... and the average will be greater than for previous generations when/if environmental factors were less positive.

The point is that within a genetic group, there is a bottom and top to the overall range of measurements. Height parameters. Genetically the average height for group members will not go below or above that bandwidth. Of course there will be individual exceptions. And there will be genetic mistakes, leading to abnormally high or low heights.

There may be studies of India, I don't know, and it is not a bad idea.

There is also a statistical matter to factor in called, "regression to the mean." Over time, the average height for a group may seem to drop below all time high measures. However that drop is not the result of genetic variation. It happens because multiple measures of the same thing over time will gradually eliminate sampling errors, bringing the measure closer to a true group average.

 

[kds1980]

I thought I had explained that. It is neither genes nor diet alone that explains height averages for individuals from the same gene pool, but the combination of both. When nutrition is better for a group as a whole, then the individual height will be more likely to approximate the ceiling, or highest number, for that genetic pool or group... and the average will be greater than for previous generations when/if environmental factors were less positive.

The point is that within a genetic group, there is a bottom and top to the overall range of measurements. Height parameters. Genetically the average height for group members will not go below or above that bandwidth. Of course there will be individual exceptions. And there will be genetic mistakes, leading to abnormally high or low heights.

I understand your point but is the genetic variation of groups of different Indian communnities is so different that variation is quite large?.
I don't think so.The difference between Indian communities is only know to Indians.Hardly anyone outside from India could tell that these communities are different regarding color,language diet.The only diffrence between them was their occupation and height
Also The communities I mentioned are also quite aggressive and also considered as voilent While Bania and some other short communnities are quite money minded and less aggressive.

 

[spnadmin]

You are making some very interesting observations Kanwardeep Singh ji. I think this would be a working analogy for what you say.

Many people outside of Oriental societies would think that Chinese, Japanese, Korean, and Vietnamese people all look the same. To each other they do not necessarily look alike at all, nor to the careful observer from outside of these societies. There are also among these societies statistical differences in bone structure, muscle density and length, and bone density and mass.

Now this I did read on the web a few weeks back. Genetic variation is much greater in the North of India than in the South. Draw conclusions from that point of departure. I don't know anything about the Bania. Is their society one that tends to be tribal in the extreme, with little if any intermingling with other ethnic groups in the region? And more importantly...has that been the case over 1 or more millennia. I am also aware, from visits to jatt forums, that jatts consider themselves to be a unique and of relatively pure genetic stock. However facts do not add up on that point.

P/S Some reading up on the Bania requires me to ask another question. Which group of Bania do you refer to e.g., Punjabi Bania?

 

[kds1980]

You are making some very interesting observations Kanwardeep Singh ji. I think this would be a working analogy for what you say.

Many people outside of Oriental societies would think that Chinese, Japanese, Korean, and Vietnamese people all look the same. To each other they do not necessarily look alike at all, nor to the careful observer from outside of these societies. There are also among these societies statistical differences in bone structure, muscle density and length, and bone density and mass.

Now this I did read on the web a few weeks back. Genetic variation is much greater in the North of India than in the South. Draw conclusions from that point of departure. I don't know anything about the Bania. Is their society one that tends to be tribal in the extreme, with little if any intermingling with other ethnic groups in the region? And more importantly...has that been the case over 1 or more millennia. I am also aware, from visits to jatt forums, that jatts consider themselves to be a unique and of relatively pure genetic stock. However facts do not add up on that point.

P/S Some reading up on the Bania requires me to ask another question. Which group of Bania do you refer to e.g., Punjabi Bania?

Well at present I was referring Bania as example there similar other communitties which are short or average height despite no difference from Taller communities.The only difference is their caste or clan whatever you say


Even among Punjabi's jatts are the tallest among all despite no difference among diet,environment or anything that differ them from other Punjabi's

 

[spnadmin]

I am not understanding your question, Kanwardeep Singh ji. Are you asking why heights are different between and among these groups? Or, why heights are not that different between these various groups?

 

[kds1980]

I am not understanding your question, Kanwardeep Singh ji. Are you asking why heights are different between and among these groups? Or, why heights are not that different between these various groups?

I am saying that in India despite living in same environment,eating same diet
Heights are different among diffrent clans or caste's of same region whether it is punjabi or non punjabi's.Only Difference was their occupation and temparament.

 

[spnadmin]

Kanwardeep Singh ji

Thanks for clarifying then. I did some research last night on this. Some of the differences are not statistically meaningful. Others have to do with the absolute amount of variation in height that is possible within what is called a "genetic" pool. More later as I even have a gene map for India. Another reason has to do with endogamy. This last point has been studied in depth.

All in all though, the distributions of genetic traits in India is very diverse. So mother nature has a lot of diversity to draw from.

Just out of curiosity, do you know if there is any web site that gives the average height for males for India overall. I have found it broken down by region, but I need a population average to test something out. If not, then I can figure out a fair estimate. Thanks.

 

[kds1980]

the wiki link I posted have average male height of Indian