Don't like the implications?

[juvenissun]

The answers you were given in this thread were summaries based on a wealth of published scientific results. If you think they are unscientific, then the problem lies in you, not in the arguments.

If so, could you remind me that summary one more time in a good sense of rigorous science? I heard words like: environment, isolation, mutation, etc. But the argument in using these terms are poor and did not really answer my question.

Let me put my question here one more time:
Black African is a tag of a race (allow me to use this word loosely).
Why should that race only be evolved in Africa?

In fact, this is just an example of my original question. Tens of posts were wasted, the question is still standing there and not moving forward a bit.

 

[Warden_of_the_Storm]

Black African is a tag of a race.
Why should that race only be evolved in Africa?

No-one except you is saying that only Africans evolved in Africa.
Read this link and you'll see that the evidence supports the theory that EVERY RACE OF HUMANS evolved in Africa.

 

[Warden_of_the_Storm]

@juvenissun, please answer this question with a simple yes or no answer: Are you asking why are the vast majority of the population of Africa is made up of black people?

 

[juvenissun]

@juvenissun, please answer this question with a simple yes or no answer: Are you asking why are the vast majority of the population of Africa is made up of black people?

No.

 

[Warden_of_the_Storm]

No.

Then what point are you trying to make?

 

[TagliatelliMonster]

Black African is a tag of a race. Why should that race only be evolved in Africa?

So.... as a response to my question.... you're asking me the same question?
I don't get it.

I'm not the one who has issues with the reality that black africans originated in Africa...

But I'll humour you and still answer it.
Why only in Africa? Because evolution is a branching tree. And populations evolve in the location they find themselves in. Because populations in other places, deal with other selection pressures, live on their own genetically isolated virtual island and thus are on their own evolutionary path.

That's also what caused the different races of homo sapiens, as has been explained to you by multiple people earlier in this thread.

Tribes / populations migrate to settle elsewhere, and in doing so are genetically cut of from the "mother" population back in africa.

Some of them split up and migrated further.

This brought settlements in asia, europe, australia, the americas, siberia, etc.

For generations, these populations were genetically isolated from one another and subject to the selection pressures of their respective environments. They were....-drumroll-... on their own evolutionary path.


There's this funny story a friend and biologist told me once. He asked me if I knew why Chimps are rather big, strong and impressive animals, who can be quite violent and aggressive... while their very close cousins, bonobo's, are these small playfull creatures that hump all day long...

He went on to paint a picture about the geography of the location of that mother population. Due to geological activity and other such events, a river formed which cut right through the habitat of that population, which essentially cut the population in two as well. One couldn't easily reach the other any longer.

Thing was, only one side held most of the natural enemies of the species. The other side was like half a paradise for them. Time went on, generations past....

Guess on wich side the bonobo evolved...



So...... to summarize. You ask why human races exist.

Well, the answer is, because when you have multiple populations of the same species that are genetically isolated from one another, then all those populations are....-drumroll-....(all together, this time).... on their own evolutionary path.

You then asked why the same race doesn't evolve in 2 independent locations at once.
Ok. The answer to that is.... because, again, genetically isolated populations of the same species are..... (you know the drill by now, I hope).... on their own evolutionary path.

 

[Speedwell]

Black African is a tag of a race.
Why should that race only be evolved in Africa?

In fact, the current theory is that we all originated in Africa, so very likely it is lighter skin which evolved later outside of Africa, higher levels of melanin being retained where it provided some advantage--as in the aboriginal population of Australia. But "black" people in Australia are not called "black Africans." There are other peoples around the world's tropics with high melanin levels who are called "black" but not "black Africans." They have also, and despite retaining a tendency to high melanin levels, developed other characteristics due to differing environments which distinguish them visually from people still living in Africa. To be a "black African" you pretty much have to come from Africa, as the epithet suggests.

 

[PsychoSarah]

Because it takes too much time to be observed, so it is a myth.

No, it is easy to observe. For example, there is a species of lizard that diverged from the source population into having a completely different digestive tract in less than 100 generations. Not to mention how easy it is to see huge changes in bacteria in a matter of a few years. To make the changes noticeable to us, we either have to observe the population of macroscopic species for more than a human generation, or observe a microscopic species. If humans lived longer, it'd be easier to see evolutionary trends, since we'd live for more generations of the species being observed.

 

[juvenissun]

very likely it is lighter skin which evolved later outside of Africa, higher levels of melanin being retained where it provided some advantage--as in the aboriginal population of Australia.

Why don't you take that advantage?
Don't reply. Save the story for your child. I am not interested.

 

[juvenissun]

No, it is easy to observe. For example, there is a species of lizard that diverged from the source population into having a completely different digestive tract in less than 100 generations.

Why did that lizard do that?
There are millions of other species, why is that lizard the only known case of such kind of evolution, or any kind of evolution? If evolution were true, won't you expect that at lease one hundred species out of a million are doing observable evolving at any time?

 

[Speedwell]

Why don't you take that advantage?
Don't reply. Save the story for your child. I am not interested.

So what's your answer?

 

[Gene2memE]

The lizard didn't "do" it - genetic variation and natural selection via differential survival rates did.

As to the "why" - the Italian Wall Lizards were transported to a small island with fewer insects and different and more abundant vegetation.

In response, the lizards gained novel gut structures to slow digestion, larger heads with more powerful bite force, shorter hindlimbs and lower maximal sprint speeds, increased average size, lowered territorial aggression and higher overall reproductive rates. They also out-competed the previous dominant lizard species on the island, rendering it extinct.

Italian Wall Lizards are far from the only example of rapid morphological change in organisms, there are hundreds (if not thousands) of documented examples:

Chicago-area white-footed mice
Tri-colored squirrel
Deer mice
Barn swallow
North American stream fish
Hudson River tomcod
Three-spine stickleback
Cichlid - one of my favourite examples, as there are roughly 500 new species in one lake in the last 1.5 to 2 million years.

 

[juvenissun]

As to the "why" - the Italian Wall Lizards were transported to a small island with fewer insects and different and more abundant vegetation.

In response, the lizards gained novel gut structures to slow digestion, larger heads with more powerful bite force, shorter hindlimbs and lower maximal sprint speeds, increased average size, lowered territorial aggression and higher overall reproductive rates. They also out-competed the previous dominant lizard species on the island, rendering it extinct.

How do you know it was a Italian Wall Lizards? Has anyone observed the change from the beginning to the completion, even in a laboratory? Has anyone found a Italian Wall Lizard which IS CHANGING on that island? Why not?

 

[Speedwell]

How do you know it was a Italian Wall Lizards? Has anyone observed the change from the beginning to the completion, even in a laboratory? Has anyone found a Italian Wall Lizard which IS CHANGING on that island? Why not?

Because individuals don't change. That's not how evolution works.

 

[sfs]

If so, could you remind me that summary one more time in a good sense of rigorous science?

When you can look back a couple of pages and read the summary for yourself, you want me to type it in again? No. Also, what are your qualifications to decide what's rigorous science?

I heard words like: environment, isolation, mutation, etc.

You also should have heard words like "vivax malaria" and "high altitude".

But the argument in using these terms are poor and did not really answer my question.

Right. Here's the problem: you think the argument is poor. You don't know why the argument is poor; in fact, you've been unable to say anything coherent about the argument. You haven't gone and read the original papers. You don't seem to pay any attention to the summary that you've been given. All you know is that something is wrong. As I said, the only faulty part here seems to be in your comprehension.

Now, do you have any substantive objection to the answers you've been given?

Let me put my question here one more time:
Black African is a tag of a race (allow me to use this word loosely).
Why should that race only be evolved in Africa?

Because "African" means "from Africa". Beyond that, I don't know what you're asking. Are you asking why different populations around the world didn't evolve identical responses to similar environments? If so, that's because there are often multiple ways of achieving the same result. Sometimes the ways are just about identical, though, as in the case of lactose persistence.

 

[juvenissun]

Because "African" means "from Africa". Beyond that, I don't know what you're asking. Are you asking why different populations around the world didn't evolve identical responses to similar environments? If so, that's because there are often multiple ways of achieving the same result. Sometimes the ways are just about identical, though, as in the case of lactose persistence.

Africans are black. They are "more black" than other dark color people (there are other unique characters in associated with that race, such as the shape of their skull, but I could not describe it precisely). It is a simple question to ask why.

By the way, are you teaching? It seems to me that you do not.

 

[Speedwell]

Africans are black. They are "more black" than other dark color people (there are other unique characters in associated with that race, such as the shape of their skull, but I could not describe it precisely). It is a simple question to ask why.

Actually, they come in a variety of shades. And there are other dark colored people--Australian aborigines come to mind--who are generally darker than most Africans.

 

[juvenissun]

Actually, they come in a variety of shades. And there are other dark colored people--Australian aborigines come to mind--who are generally darker than most Africans.

I don't think so. Is there any study to compare their skin darkness?

 

[Speedwell]

I don't think so. Is there any study to compare their skin darkness?

Probably, but I've been there and seen them.

 

[Herman Hedning]

I don't think so. Is there any study to compare their skin darkness?

You may find it interesting to read the wiki page on dark skin. It describes how skin color is a direct adaption to the amount of UV radiation at the place of settlement, and how populations can lighten and re-darken as they move around. Here is a quote:

More recent research has found that human populations over the past 50,000 years have changed from dark-skinned to light-skinned and vice versa. Only 100–200 generations ago, the ancestors of most people living today likely also resided in a different place and had a different skin color. According to Nina Jablonski, darkly pigmented modern populations in South India and Sri Lanka are an example of this, having redarkened after their ancestors migrated down from areas much farther north.