Different races = different species (evolution)

[Djamila]

If human beings had not invented various technologies that made global interaction an everyday reality, is it possible that the world's different races - Caucasians, Slavs, Africans, Asians, and so on - would've evolved into different species?

By different species I mean only to the least different extent - two closely related animals that can produce sterile offspring, for example giraffes and zebras.

Is it possible? If so, is it probable?

[Phil Osophy]

It is probable that we would have eventually evolved into different species that would have been better adapted to different conditions in various parts of the world. Differences in skin colour are a first (but very minor) step in that direction. Unless there is a global catastrophe it seems unlikely that it will happen now.

[Halcyon]

Originally Posted by Djamila

If human beings had not invented various technologies that made global interaction an everyday reality, is it possible that the world's different races - Caucasians, Slavs, Africans, Asians, and so on - would've evolved into different species?

By different species I mean only to the least different extent - two closely related animals that can produce sterile offspring, for example giraffes and zebras.

Is it possible? If so, is it probable?

Interesting questions.

Well, geographical isolation is what caused humanity to diverge into various races - so if that isolation was maintained for a million years or so, i.e. noone traveled intercontinentally for that time, then yes, eventually it is likely that the separated populations would become sufficiently different from one another to prevent successful breeding and we'd have 4 or 5 species of humans.

[GeneCosta]

giraffes and zebras.

I don't think it would be to that extent.

Humans exploit the environment around them with the use of complex tools while even animals using basic tools live by it. There would be no cause for evolution if we weren't at some odds with nature. Giraffes need(ed) their long necks, while humans can just build ladders.

All my opinions, though.

[Djamila]

But maybe we are, who knows. They've shown that some families involved in prostitution in Kenya have developed an immunity to HIV and AIDS. I saw a special once about how Houston, USA, has the fattest people in the world - but also healthy-weight individuals with the highest metabolism in the world.

I think we're still being tweaked and perfected as a species.

[Halcyon]

Originally Posted by GeneCosta

I don't think it would be to that extent.

Humans exploit the environment around them with the use of complex tools while even animals using basic tools live by it. There would be no cause for evolution if we weren't at some odds with nature. All my opinions, though.

I took Mila's post to be a hypothetical about would would happed if we hadn't advanced past, say Bronze age tech.

Despite our tool use, the environment still caused humans to diverge into the races we do have. But evolution could also well be pushed via sexual selection to the point where inter-racial breeding could become impossible, the possibilities are quite limitless as to how humans could change given sufficient isolation.

[PureX]

I think humans are far too violent and self-centered to ever allow such a similar-yet-different species to evolve. Human beings already try to annihilate each other over such simple differences as skin color and cultural disparity. If any real differences were to manifest, I'm sure one or the other side of the difference would have to eliminate their perceived opposition.

[Jaymes]

If they had stayed apart for long enough, I see no reason to think they couldn't.

[Booko]

Originally Posted by Djamila

If human beings had not invented various technologies that made global interaction an everyday reality, is it possible that the world's different races - Caucasians, Slavs, Africans, Asians, and so on - would've evolved into different species?

By different species I mean only to the least different extent - two closely related animals that can produce sterile offspring, for example giraffes and zebras.

Is it possible? If so, is it probable?

It would be technically possible if those populations were isolated for a long period of time. "Long" in this sense is not 1000 years, or 10,000 years, but probably more on the order of a million years. The only technology you need to prevent speciation is feet and the will to move, which we seem to have that in abundance.

Given humans inability to stay put over that length of time, I wouldn't think it's probable.

There are species that developed parallel to us, but it's a debate current in biology as to whether some of these species could actually breed with us or not.

Neanderthals are the usual (and more recent) example: did they intermarry? Could they? Are their genes to be found in Europeans today?

As for the comparison of skin color to define race, I should think there are more important factors than outward appearance. We see trends in blood types across various populations, for example, and I would argue that blood type would have a greater implication physically than the amount of melanin in ones skin, which is trivial at most.

I look forward to seeing some of our resident biologists weigh in on this thread.