In your opinion, will the human race ever split off into different sub species similar to Neanderthals and Homo Sapiens? Will something similar ever occur again?
Depending on how you define “Species”. If you’re talking about differing phenotypes, then one might argue that the Chinese and the Nigerian are different species right now. If you mean “able to produce fertile offspring”, then I highly doubt we’ll ever see that split again.
Perhaps more extreme differences, such as distinguishable difference in physical or mental capacity. Will another race evolve from our current “template”?
Define “superior” and "inferior,’ because those sound like value-judgement loaded terms. Every living species is good enough at what it takes to survive in its own niche.
Given that humans currently are living in almost every geographical region, and are highly mobile, I find it hard to picture just what could cause a speciation event.
(bolding mine)
One would also be going against every single scientist to ever study humans/biology since Darwin. However, the idea that one can split humans into different species based on “differing phenotypes” would be plain laughable even to Linnaeus in 1735.
yearIt is theoretically possible. There is no biological or evolutionary reason why one or more populations of humans can’t mutate and speciate, but it would require particular circumstances which don’t exist right now, and don’t appear likely to exist.
The population or populations in question would have to be segregated or isolated from the rest of its species, some kind of benefical mutation would have to occur, and some kind of sorting mechanism (e.g. natural selection) would have to be in play.
Currently, humans are subjected to very little in the way of natural selection or isolated populations. There are some tiny, “uncontacted” populations who might have some kind of genetic variation going on, but it would take thousands of more years for any of that to result in speciation.
Theoretically speaking, I think a plausible scenario for new species calving off from homo sapiens sapiens could come as a result of hypothetical human colonies on other planets/moons, etc. There you could at least theoretically have a potential for both genetic isolation and natural selection pressures, and it would still take thousands of generations.
**Human species ‘may split in two’ **
Evolutionary theorist Oliver Curry of the London School of Economics expects a genetic upper class and a dim-witted underclass to emerge.
A 2006 article from BBC.
Did he get right which class would be dim-witted?
This is pretty much the stock answer I give to all these future of human evolution threads:
We can’t look at our evolutionary past and extrapolate it into our future. Our technology has changed the environment a huge amount, and continues to change it far faster than natural selection can keep up with.
Speciation seems unlikely to me, given that I could board a plane tomorrow and be screwing the person most genetically different to me within 24 hours.
(I’m being slightly silly phrasing it that way but you get the point: we aren’t geographically isolated any more.)
That said I can imagine a couple of specific scenarios where it could happen:
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A nuclear winter, say, with populations existing in separate bunkers for centuries.
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If genetic engineering becomes socially acceptable and massively developed, some people may have a greatly optimised genome such that they are incompatible with “wild type” humans.
It seems likely to occur if we were to colonize other planets and then lose our FTL travel for a long time, causing the worlds to be isolated from one another.
Wait, did I say likely?
although I don’t think that would be superior / inferior - just better adapted to the planets in question
or just some random crap
Even in isolation, it might take a very long time for the combination of mutation and variation to produce a geneticly distinct ‘human’. And the attribution of ‘superiority’ or ‘inferiority’ may not even apply. The genetic change might propogate through an isolated population without an overall effect on the ‘humans’ that could be detected.
Who said we’d have FTL to begin with? It seems quite plausible to me that the colonists of other worlds would either be in some form of suspended animation on the trip, or in a self-sustaining generation ship, in either case taking thousands of years for the trip.
If he said my 3rd period Econ. class he did! 
American Indians were split from the rest of the Human race for at least 12,000 years, and Australian Aboriginals for an even longer period then that, and neither population developed into its own species. You apparently need some pretty seriously long time intervals for humans to speciate. I’d say barring a scenario like Chronos describes, where human colonists set out for other planets on trips that take thousands of years and thus are more or less permanently severed from the rest of Humanity, its not going to happen.
No purely social institution that bars humans from mating is going to last long enough to create different species, and even if such a social institution did last thousands of years, one characteristic of the present human race is to go ahead and have sex with each other even when said sexual relations are ill-advised, dangerous, taboo, illegal or dumb. Over the centuries there’d surely be enough “cheating” to insure genetic mixing between populations.
You would need some kind of change that would have a big effect on survivability or reproduction rate to get new gene formations that would become dominant even within the isolated population. That would mean some pretty unusual conditions that humans couldn’t override through technology. We might be talking millions of years of isolation to get the result suggested in the OP.
Even in a case like North Korea, where there is not only isolation, but lack of food or some other serious stressor, it would still be unlikely. What reason would there be for a chromosomal change?
Maybe a massive sunspot or other radiation exposure which damaged the DNA, but allowed continued reproduction until a few very different babies survived? Or maybe a virus which disrupted the genome, but produced some sort of throwback?
Then there’s always that X-Files show about the extreme inbreeding. ::shudder:: Why is it every time I’ve almost forgotten that horrid thing something happens to wake it up in my brain again?
My thought too - the natives of South America probably last had contact with an Aisian - from the siberia area - about 14,000 years ago. Conisdering how remote the chance that they had any common “genetic contact” with whites or southern africans in the last 20,000-plus years. Plus, IIRC the aborigines of Australia split off from the herd, so to speak, about 40,000 years ago - only the odd trade contact with New Guinea after that, so minimal genetic exchange.
Yet white people and Africans had no problem reproducing with native AMericans, and aboriginals are still able to cross-breed with others.
OTOH, genetic drift in terms of adaption to situations like black skin or afro hair for strong sunlight, white skin and baldness for poor-UV conditions, flat noses for severe siberian climates, and the peculiar adaptions for the high andes that some South American Indians have… Humans can adapt fairly well to a particular situation like altitude within the 12000 years (about 480 to 600 generations?) that they have had the environment.
but what is speciation, technically? Horses, donkeys and zebras can interbreed (although they do not produce fertile offspring I understand…) It will be a peculiar situation that can isolate humans the way horses, zebras and donkeys were - enough to change radically…
Yep. For large mammals like humans, the rule of thumb is at least 1M years. And that would be the under in the over/under calculation. Humans and Neanderthals split about 500 - 750k years ago, as a reference. And the latest and greatest evidence implies we did interbreed once the populations encountered each other again.
Unless there is a catastrophic event on earth sending us all back to the Stone Age, or if we colonize other planets, we’re all going to be one species. And even in the event one of those things happens, it will take a really, really, REALLY, long time for speciation to occur.
Now, we might genetically engineer ourselves into different species, but by then we’d probably have the technology to overcome that barrier, too.
There’s really no need for strong selective pressure to cause a speciation event. Isolation followed by simple genetic drift often does the job. The specific changes have been identified in several Drosophlia species, as well as other species pairs. Examples like Africans <-> Native Americans really don’t apply, because although those populations haven’t been in contact with each other, there has been significant gene flow through the different populations. If Native Americans had remained isolated for a few million more years, maybe.
:smack: Of course, so I guess my nuclear winter scenario isn’t really gonna cut it.
I stick by my second suggestion though: if genetic engineering becomes hugely advanced, we could create super humans so different to us that they couldn’t breed with us.
But obviously in such a scenario, all bets are off, as it would really depend on what objectives are most important for us when the tech becomes available.