Relation Between NT-SF, Natural Selection And Longevity

Of late I have been thinking about the MBTI types that are meant for survival and the ones that are not.

The statistics of percentage of people by MBTI type is available here. And you can see that the NT type, with all 4 subtypes ENTP, INTP, ENTJ, INTJ, forms about 10% of population while FP, with all 4 subtypes, is about 43% of the population.

If you split the types as NT, NF, SF, ST, each of the four types in theory should be 25%. As you can see, NT numbers are far lower at 10% and SF is higher at 43%. And majority of the SF's are women. Obviously there must be a reason why SF percentage is much higher than NT.

From another view point, we also know that the longevity of women is about 4-5 years than the average male as mentioned here and here. Women are in a way "fitter" than men and survive better. And perhaps for the same reason SF percentages are higher than NT's. Women form a much higher percentage of SF's than of NT's. SF is primarily a feminine trait while NT is a more masculine and cerebral trait. When SF percentages are so much higher than NT percentages in the population what does it say about the "fitness" of NT in the society?
By fitter I do not mean physically stronger. I refer to the fit as it is used in the expression "survival of the fittest".

Now we have the following data points. 

• SF percentage is much higher than NT percentage in the population. 
• Women live longer than men.
• Women form a higher percentage of SF than of NT and women outnumber men in SF.

What do these data mean?

The theory of natural selection says that we pass on those genes which help our species to survive and breed better. NT percentage is perhaps lower because we do not pass on the NT genes as often as we pass on the SF genes and that, in turn,  may be because NT's aren't well adapted to the environment. And as we have seen in the bullet points above female longevity is higher than male longevity.

Incidentally, research seems to indicate that our brain size has been getting smaller over the last 10 to 20 thousand years as per this, this, this and that we are becoming less intelligent than we were earlier. This seems to tie in with what I mentioned in the previous para - may be NT numbers (note that N's are more intelligent than S's) were higher earlier and these have become much less now. Even NF numbers are much lower than SF numbers. 

A quote from the 1st link: "Another likely reason for this decline is that brains are energetically expensive and will not be maintained at larger sizes unless it is necessary. The fact that we increasingly store and process information externally—in books, computers and online—means that many of us can probably get by with smaller brains. Some anthropologists have also proposed that larger brains may be less efficient at certain tasks, such as rapid computation, because of longer connection pathways. The way we live may have affected brain size. For instance, domesticated animals have smaller brains than their wild counterparts probably because they do not require the extra brainpower that could help them evade predators or hunt for food. Similarly, humans have become more domesticated. "

Quote from the 2nd link: "Over the past 20,000 years, the average volume of the human male brain has decreased from 1,500 cubic centimeters to 1,350 cc."... "The impact of these mutations remains uncertain, but many scientists say it is plausible that our temperament or reasoning abilities shifted as a result. Numerous phone calls later, it dawns on me that the world’s foremost experts do not really know why our organ of intellect has been vanishing. "

As per the 3rd link, "Geary and his colleagues used population density as a measure of social complexity, with the hypothesis that the more humans are living closer together, the greater the exchanges between group, the division of labor and the rich and varied interactions between people. They found that brain size decreased as population density increased. "As complex societies emerged, the brain became smaller because people did not have to be as smart to stay alive," Geary told AFP."

If this trend continues we will see that the brain continues to shrink, that socialization (F) becomes more critical than abstract thinking and NT - SF difference in population will become even more marked than it is now.
And either the future population will have more women than men or the population will have more SF's in it. Men also will become SF's increasingly. The 16 MBTI types, in future, may change into a different set of and perhaps numbers of types also.

One data I really want to get my hands on is the longevity statistics of NT and SF. I want to see if longevity of NT is lesser than that of SF.  I guess it will likely be so. 

In a lighter vein, thinkers should consider switching to feeling (becoming feminine) when they still can. Warren Buffet seems to feel the same thing - see "peals of laughter" here http://www.financialexpress.com/market/warren-buffett-predicts-dow-at-over-1-million-and-thats-in-a-conservative-estimate/865762/

Additional reading:
https://www.washingtonpost.com/news/business/wp/2017/07/27/grocery-stores-are-adapting-to-more-male-shoppers-who-they-treat-like-knuckleheads/?utm_term=.1026029792f9