When The Human Race Evolve Out Of Africa, Why Did Facial Features & Hair Textures Change?

Question

Excluding eyes, which makes sense (harsh sun, wind etc.), why did hair texture, nose & lips change. What environmental factors could have caused these biological ones.

Okay for the racists-apes have thin lips & are very hairy the opposite of the traits of (generally speaking-yes its true) of black people.

For those white ppl who say you evolved out of Europe where's the proof?

For the "What differece does it make, people are people"-people-relax its a pretty fair question, & an interesting one if you think about.

Answer 1

These are things I have read in various different sources. One of which I believe may be Cecil Adams (google him...he does great research!): Light skin & caucasian features (high bridge noses): historically have lived in northern climates with colder weather and less sunlight. Lighter skin reacts with sunlight differently than darker skin: it produces more vitamin D in reaction to sunlight than darker skin does. This would be important where sunlight is weaker. Also higher bridged noses (theoretically) have more of a protective effect on the sinus cavity and mucous membranes when the weather is very cold. My own personal opinion on tighter, curlier hair, which one tends to find in very warm, humid climates is that it can act as a sort of insulation to protect the brain from over-heating. That's just my own theory, so take it as a grain of salt...I'm no expert, just have pondered these things now and then. Everything I have read about the biological and physical effects of different racial characteristics gives me the impression that it is all really theoretical. But some of the theories seem to make sense, when you think about the way different extreme climates effect the body. But you know, when you look at mitochondrial DNA (please look that up on Wikipedia for a better explanation than I can give), we are all from the same lineage, no matter where in the world our various ancestors settled. I myself prefer to think of humanity as one family with endless variations.

Answer 2

I don't know that anyone knows for 100% sure, but I've read some interesting theories. For instance, Europeans may have needed longer nasal passages to warm the air. Also, lips are very definitely sexual. They flush when a person's aroused, which explains the popularity of lipstick The lips of white people are really obvious- pink against pale skin. It's a really clear erotic sign. That pink wouldn't show up as clearly on dark skin, so perhaps their lips evolved to be larger so they'd be more obvious. Lips also plump up when a person's aroused, so it'd do the same general thing.

This is all speculation, of course. There might be other reasons, or it might just be chance. Often, families have certain features that appear really strongly in all the members. Everyone in my family directly related to my grandfather has a strong, jutting chin (alas). Some of the racial traits might simply be like family traits only widely spread.

Answer 3

I like how you point out that apes have thin lips and are hairy. Never thought of that, but you're right.

Scientifically, i would say natural selection. People with Black skin CAN have straight hair (aboriginals of Australia, the original Dalit inhabitants of India), as well as narrow, long noses (Dravidians). I think that white people evolved out of African albino's who had straight hair and long noses with small nostrils. Those features may have been advantageous in Europe's formerly frozen climate. The hair keeps your neck/back warm. The nostrils allow less cold air in your lungs. The pale skin lets more sunlight in to make vitamin D, which your body needs to live.

From a philosophical, abstract and even biblical approach, some Afrocentric scholars say that white people evolved out of Black people's recessive genes. Some other somewhat strange theories use passages from the Bible. Add me as a contact if you want to know that theory, it's controversial.

Answer 4

Awesome question. I have answers but never put them all together until now.

Noses: Nose shape is in response to moisture or lack thereof in the air. The differences in nose size and shape can be explained by a need to moisten arid air before it enters the lungs and by a need to conserve the moisture in the air being exhaled.

Hair: The reason humans still retain hair in the places they do is for a few basic reasons. For arm, leg and head hair it is for protection from the elements. Curly hair as a characteristic of Africans comes from the need to not only protect but also to diffuse heat. The tendency towards straight or wavy hair in European stock is to act as insulation and conserve heat.

Lips: I am unsure of this feature's cause. Of course it could be as simple as sexual selection. Not all features serve to aid in survival, in fact some make no sense at all except that someone finds it attractive.

As to the ape issue, we have been separated from our nearest ape relative (Chimpanzee) for somewhere between 5 and 8 million years. More than enough time for selection on a whole hos of levels to have created large differences in phenotype (if not genotype) between us and the other great apes.

Answer 5

The features varied slightly, in different groups, due to the needs of those people to survive their climates. Eastern Europeans are only so fair-skinned due to very little melanin production, in other words, to help them make the most of the little UV they could get.

The groups that wound up having very dark skin developed it in order to help shield them by making a lot of melanin as they needed to adapt to having a bit too much UV so the increased melanin would serve as protection to the skin. Melanin, as everyone knows, determines the lightness or darkness of your skin and the other physical features changed from group to group for the same reason. Survival.

So, the races aren't actually "different" as some folks think of them, the only difference is that their ancestors had different needs in the days before Central AC/Heat and other modern development.

Answer 6

ah, the mysteries of life. genes can be dominant or recessive.
put two recessive genes together and you get a change in trait. keep intermarrying and reinforcing the new trait...it can lead to so many possibilities.
warmer temperatures require less hair to keep body temp up, colder temperatures requires more hair. strong sun, more melanin needed. different body types thrive in different temperatures.
genetic scientists love to play this game. there's also the game called panmixis: if all the races and traits were mixed together, what would the resultant body look like?

Answer 7

I agree with TJB. I don't know though whether all modern human beings originated from Africa but I'm ok with the idea. Some of the elders in Africa also think it is a crazy theory.

For those that havent yet stumbled on: https://www3.nationalgeographic.com/genographic/atlas.html
check it out and see if it makes sense to you.

Answer 8

Typically when people think of Africans, they think of West, South or Central Africans... seldom North or East Africans. Africans are a very diverse group but excluding North Africans, they all have the tightly coiled hair & dark skin. Facial features, body & skull shapes vary drastically. The hair of most Africans is a means of keeping the sun off their heads & keeping the brain cool. Due to the slave trade most Africans in the Industrialized world & Americas are from West or South West Africa (Haplotype L2.) Look at East Africans (from the horn of Africa) and you will find them far more like North Africans & ME people in all but hair & skin color. Dark skin keeps the sunlight from depleting folic acid & is beneficial in southern climates, but it also reduces the amount of Vitamin D the body can make from sunlight. Therefore women with dark skin would tend to get rickets & die in childbirth in norther climates.
We are in the midst of sequencing the complete Neanderthal genome & hope to finish in 2009. This will tell us if they contributed any genes to Asians & Europeans. I strongly suspect the Neanderthal contributed at least one gene to those migrating through the ME. Due to the longer association with Europeans it is possible they contributed some adaptive genes for cold climate. Alas, we have to complete sequencing of the Nenderthal genome to prove or disprove the source of a number of genes we are looking at.

Answer 9

I'm not so sure all tribes evolved from a particular part of the world. And actually, I thought we evolved from the middle east.

At any rate, if you wanted to stir the pot, you certainly did it.

From what I can remember from a conversation I had years ago regarding this very topic, it's all in the demographics. In order to live, tribes and packs of people traveled where there were enough resources for them to survive on.

Lord knows how they looked when they got there, but after a while a particular breed of people acclimated to a particular physical region and voila', we got the Norwegians, the Swedes, the Africans, the Asian and all the other races and their features that developed along the way.

I hope this answers any questions you had.

Answer 10

Yes everyone came from Africa, but as they traveled out further, their bodies adapted to the weather conditions.