Why the structure?

After doing some research I found some theories that spoke about the facial structure of Africans. I don't want  to categorise a whole culture into one group but if I were to explore into different countries and tribes I could be here awhile as each is unique and slightly different. For this reason I am going to do a general summary of a theory. Africans from different parts of Africa vary in facial structure. But I am just going to cover the majority. It is a stereo type to say that all Africans have a wide nose and big lips however this is not true.


Some of the theories I have read believe that African natives have a wider nose to breathe more air in areas of lower oxygen levels. I think that this makes sense because Africa has a high altitude especially in places such as South Africa, however surely this would mean that African people should have a larger lung capacity verses another culture? We can see a similar structure in the noses of many Indian and Chinese people all which are warmer areas. I once went to the doctor and I spoke to him about why on cold days when you breathe out your mouth water vapour appears yet on the same cold day breathing out your nose does not have the same affect. We then spoke about how there is a part in your nose that heats the air when you breathe it in so on a cold day it is better to breathe through your nose as your mouth does not do this. This all got me thinking.


Why is it that majority of Caucasians have a thinner nose than other cultures? Going back a few years when the majority of Caucasians lived in places in Northern Europe (a much colder region) it begins to make sense. If nostrils on a human being are smaller the easier the air is to heat, such as in colder regions like Northern Europe how ever in hotter regions such as Africa and China nostrils can be wider because heating the air before intake into lungs is not as important and as altitude is higher more air may be needed to get a higher level of oxygen with each breath. So this may explain the difference in facial structure between noses in different cultures.
 as an example I have used the great Nelson Mandela of South Africa.

Image from google, http://bit.ly/ykH16G