Human Races

Hello, this is my first post and I'm more of an astronomy guy than a biology guy, but I was just wondering how evolution explains the different races of humans (like African, Asian, Hispanic, etc.). How do different races come about? Were there different races of primitive man? I've read that Africans can naturally jump higher (in general, of course) than most other people because of the way their lower legs are constructed, but that this also causes them to have to put more effort into swimming. Is there any validity to this? If so, are there are any more differences like this between other races?Basically, I'm just kinda looking for a run down on the different races of humans. Sorry if any of this sounds stupid; I just recently became interested in science and even then I find astronomy to be the most interesting, not biology. Thanks!

OK, I'll try to help you with this ?(maybe). Scientifically speaking, a race is a subspecie of a specie; therefor Humans are a single species and "Caucasoid", "Negroid", "Mongoloid", etc. are possible subspecies, but there is still some degree of controversy about this within the Biological and Social Sciences. I would say that at present it's a convenient classification for scientific use, and I in no way agree with racism. Remember this: We are all human, and for a few very good reasons. One reason has to do with Biology: We can all interbreed. I'm afraid that my knowledge of how 'races' came about is severely limited at this time. Some biologists and anthropologists say that there is no such thing as 'race' in humans. Maybe someone else can answer about jumping higher, swimming, and the origin of 'races'. And NO, it doesn't sound stupid; your doing something all curious people do, and it's admirable: your asking ?'s.

As it turns out there's really no such thing as race. For instance they did a study in Brazil (a very racially mixed society) and found that there were no biological or genetic markers that consistently matched what "race" a person identified or was identified as.It isn't really a surprising finding. Consider this: You may be taller than other people. (I am.) In fact your entire family may be taller than the average person where you live, or even your entire block. Does that mean that you're of a different "race"? Not likely. Humans vary, and not one "race" of people varies outside of the normal range of variation for individual humans.When you try to construct a taxonomy of race, you also come into problems. Every time you propose one kind of race - African, or Caucasian - you run into people - lots of them - who are right smack in the middle between that race and another. Like the Finnish, or Arabs.Race is a culturally constructed phenomenon, not a biological one. There's no scientific "test" for race. Black people may have longer legs on average, but taller people usually get paid more on average - and being black is no more likely to make you taller than being taller automatically means you'll be paid more than the short guy.I mean, how would you go about determining if two different people are of a different race?

So, since we're so mixed up at this point in time, it's pretty much impossible to determine individual characteristics of a specific "race" if there are any at all? According to our evolutionary studies, were most forms of primitive man clumped together in the same area or not? For example, let's say Species X evolved in Egypt. Did Species X stay only around the Abydos region or were there clumps of Species X at Giza, Cairo, and Abydos? Or was Species X evenly scattered throughout a region with no central point of high population density?I'm just trying to understand why people of different races are concentrated in certain areas of the globe and when primitive species of man started to be broken down into significant racial groups. Is it climate that affects the level of melanin and facial structure? In which case, racial groups were formed when a species of man started to spread out into significantly different areas of the globe. Do different types of dogs run parallel to different types of humans? Is collie, chihuahua, and German shepherd (as dogs) parallel to African, Caucasian, and Asian (as humans)?NOTE: I'm not racist, by the way, and I'm not trying to bring on some idea of one pure race being better than another, I'm just interested in what makes us different and how we grew to be different.[This message has been edited by Tsegamla, 10-18-2003]

In the basic sense of natural selection, yes, probably. Africans have near-universally dark skin because it's so sunny where they are, and too hot for clothing. Therefore persons with extremely light skin did not leave as many children as dark-skinned folk.So, yes, the climate did influence which traits are more likely to be prevalent in a given geographical area. No, we're nowhere near that different, as far as I know. On the other hand I don't know that there's any genetic test that will distinguish between different breeds of dogs, either.Think of it this way - what would be the point of a system of "race" classification? Is it in any way predictive? (Not at all.) You may call that guy "Indian" or "Arab" or even "Black" but for all you know he's just a white guy with a tan. I have a friend, you'd swear he was from Spain - very swarthy, black hair - but he's of 100% Swedish ancestry. He's just got dark skin.Not only is race non-existent, it's useless.

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In the basic sense of natural selection, yes, probably. Africans have near-universally dark skin because it's so sunny where they are, and too hot for clothing. Therefore persons with extremely light skin did not leave as many children as dark-skinned folk.

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So, yes, the climate did influence which traits are more likely to be prevalent in a given geographical area.

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But I thought that things like tanning weren't hereditary. If I got a good tan and got a girl with a good tan pregnant, the child wouldn't have a good tan, right? But I suppose that would be different if a group of people consistently stayed in a particular climate for their whole lives. Why is facial structure different? You couldn't give a black man white skin and successfully pass him off as a Caucasian (well, you could, but he'd look weird).

Well, it isn't. The capability to tan is, and your basal levels of melanin, are, but there's no difference physically between a man who has dark skin because he was born that way and one who has a deep tan. It's the same pigment. Quick - explain to me the difference in facial structure between these two people:
There's hardly even a difference in skin color. In fact I'd be surprised if anybody could accurately determine the race of these two people if they weren't already famous actresses.[the images show up in the preview, but not in the post. Curses! Admins, can you help?]fixed photo urls and deleted now extraneous links - The Queen
[This message has been edited by crashfrog, 10-18-2003][This message has been edited by AdminAsgara, 10-18-2003]

That's not fair though, we all know that Halle Berry doesn't have that regular African styled facial structure. Her's is more Caucasian. Here, I just searched "black male" on Google image search and I'm using first page results: If they simply had white skin, they wouldn't just blend right in. Generally, most of the black men I've known, including my best friend in 8th grade, have had wider noses (and somewhat larger lips, now that I come of it). Halle Berry isn't really a fair example, in fact, I think she's half and half to begin with (might be wrong though).EDIT: Actually, Halle Berry's nose is plenty wider than Natalie Portman's and looks like her lips are bigger, but that could just be the angle. Still though, I can't pick out all the things that make the traditional African facial structure the way it is, but it exists and it's noticeable regardless of skin color.There's also other physical characteristics like Koreans and other Asian groups have the slanted eyes. It's not really just the skin color; eyes, facial structure, and maybe more.[This message has been edited by Tsegamla, 10-18-2003]

That's what I'm saying, though. You can hardly talk about a "black" facial structure if somebody can be considered black and not have it.Any time you can hold up two people of different race and say "they're different for such-and-such reasons, so those differences must be racial" I can find to people considered to be of the same race who are different in the same way, or two people of different race who lack that difference.See how race is meaningless? The distinction is only in your mind. Yes, there's average physical differences between groups identified as different "races". What I'm trying to show you is that those differences aren't sufficient to define race. Sure, but there's Caucasians and Africans with slanted eyes. These aren't fundamental things that separate races - they're normal variation within the human species.

And of course at this point we're only talking about people who identify as one race. What about people of mixed race? Perhaps you could tell me off the top of your head what race Tiger Woods belongs to? Or Mariah Carey?

I understand what you're saying, and I agree that at this point in time, we've mixed so much that any real distinctive qualities are gone as far as absolute means of identification goes, but I'm talking about the core characteristics of each pure race. It's just like if we have a million shades of gray, we can still define 100% black and 100% white. Let's say man evolved as one species in Kansas and then broke off into 5 groups: (1) Canada (2) Mexico (3) Ecuador (4) Northern Argentina (5) the southern tip of South America. Then alien ninjas from the planet Zaptron came to Earth and made laser walls to permanently separate the different groups. Would these different groups eventually develop their own qualities similar to our races due to their different environments?I understand that realistically there is no deciding factor on race, but if it weren't for interracial mating, would different races develop certain undeniable characteristics that are pretty much exclusive to that race?EDIT: Also, I'm not saying that all people in Africa or all people in Asia or all people in Europe look the same. There seems to be a spectrum of race and we draw the lines at different points. Sort of like the middle east being a middle-man between white Europe and black Africa. I also get how there is a certain level of variety among humans, but certain features are still pretty much exclusive to certain races. I've never seen a white person with slanted eyes like a Korean guy I know at school.[This message has been edited by Tsegamla, 10-18-2003]

Yes, I realize that. It's possible to "define" some kind of "pure" conception of race. The problem then is that, just as in the real world you'd never be able to find a pure white color or a pure black color, you could never find a person who was purely of one race.So what's the use? Why define something that won't ever exist? If no person could be of "pure" race, why bother to talk about it? Now, you might wish to find persons who are "closest" to purity, but how could you define racial "purity" if no human can obtain it? What criteria would you use to determine the "core characteristics" of the "pure" race?This is why racism is so unscientific. Ultimately it comes right back to one's preconceptions about race. I'm not accusing you of being racist, just trying to point out that your thought process has already been tried by racists, and been found to be fruitless. If racists - who could be relied upon to have the most to gain from finding a metric for racial "purity" - can't find it, it's reasonable to assume it doesn't exist. How can you have interracial mating if there's no such thing as race?The words you're looking for are "reproductive isolation". When you take members of the same species and isolate them into multiple groups, each of those groups becomes a new species over time. This is true of all life, and has nothing to do with race. If you took 2 identical groups from the same "race" - from the same big family, even - and isolated them, you'd have a new species given enough time. On the way to that, you might find that members of one of the groups all share a characteristic that the other group universally lacks, despite an ability to interbreed, so I guess you could call them different "breeds" or "races" at that point. But the human race was nowhere close to that, not even before the modern ease of interbreeding.

All right. I agree with you on the realistic use of such information. There isn't really much of a use for defining a pure race except just for the sake of doing it. It's just something to think about it. Sort've like absolute zero, I suppose. There's also really no way to attain racial purity, and that's a good thing, because if there was then there would probably be wars between different races (or ultimately species if it had a chance to go on long enough). Basically, I understand that it doesn't work this way, but it's still interesting to think about. Just like how if a penny doubled its size every second for Avogadro's number of years, how big would the penny be? Same idea. Impossible, but interesting to think about.Hypothetically, if you did apply reproductive isolation to separate groups of modern humans, is there any calculation on about how long it would take to significantly evolve each group into a separate species?

Like all organisms, it depends on a combination of factors, including how long it takes to get a new generation, how often new mutations occur in each offspring, and specific environmental factors that could speed or slow speciation. By "species" (by the way) I assume you're referring to the standard Biological Model of Species, where any two groups of organisms that do not give rise to fertile crossbreeds are considered separate species...You'd have to ask an actual biologist, like Minnemooseus or Mammuthus. Perhaps they could enlighten us?

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In the basic sense of natural selection, yes, probably. Africans have near-universally dark skin because it's so sunny where they are, and too hot for clothing. Therefore persons with extremely light skin did not leave as many children as dark-skinned folk.

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Not quite true - partially . Skin color is a balance between two factors - damage from UV light, and vitamin D synthesis. Temperature isn't really a significant factor. Melanin, being a strongly light-absorbing pigment, protects the cells from UV damage, but limits vitamin D synthesis. In equatorial environments, there is plenty of light, so most of it needs to be absorbed. In polar environments, there is little light, so most of it needs to be allowed into the skin. Tanning is the body's response to cellular damage from light: your body reacts by having melanocytes produce more melanin. As a consequence, there is no safe form of tanning (apart from "fake" tanning methods) - the tanning itself is a response to damage occuring.What we see with races is really an early stage of cladogenesis, but we're still very closely related on the scheme of things... I wouldn't even put us at the subspecies level yet. Now, with air travel and an increasingly interconnected global environment, I think the odds of humanity splitting into multiple species are about nil, until we get major relativistic distances between human cultures.------------------
"Illuminant light,
illuminate me."[This message has been edited by Rei, 10-19-2003]