News flash! The planet will be here long after we have turned to fossils! Happened before...will happen again. Humans are just to full of themselves to think otherwise. Hey...the sixties were good to me too!
This ... makes me quite interested in what sort of 'evolution' would occur in a setting of 'infinite' modern society.
For one, culture/tech/etc, will constantly move in any given 'direction', bar any apocalyptic event. Even trying to hypothesize what the future could bring culturally/technologically is an interesting thought experiment in itself.
And I don't mean in the next 50 years ... but the next 100, the next 1000 years.
And then in terms of evolution, you are looking at MILLIONS of years.
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I mean, we came up with writing only a few THOUSAND years ago. Language probably 50,000 years ago. Hell, our species didn't even exist until around 1 million years ago, and then we finally reached some sort of "human singularity" around 50,000 years ago.
This sort of thought experiment is indeed mind boggling.
One thing to consider: Does unlimited gene flow STOP evolution? Or does it just keep the entire species going in the same direction.
Barring multiple planets and Cataclysmic events ... is there any way that geneflow would become limited, to create speciation? Clearly multiple planet habitattion without common access to FTL travel would cause this ... but if we continue to only occupy the earth?
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I don't necessarily think speciation is a bad thing, but I don't see it happening under 'normal' circumstances. But then again, the chances of circumstances remaining 'normal' for an amount of time approaching infinity begin to approach zero.
Meaning that, chances are, shit will hit the fan eventually, and thus eventually we will have speciation.
Even so ... it would likely take MILLIONS of years for such 'breeds' of human to actually become a completely separate species. That is to say, reproduction between breeds would likely remain possible for millions of years ... and with that being the case, there is always the possibility for gene flow to keep the species from completely separating.
To give some idea of what a breed is, we as humans are all one breed. Dogs on the other hand, are all one species, but multiple breeds. (I think Iguanids are also simply breeds of the same species)
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However, assuming that we DO populate different planets, and that we do NOT have FTL travel (or FTL breaks down eventually, et cetera), speciation is practically a guarantee.
Consider the movie 'Pandorum' and the difference between the recently awakened and those that were on the ship for quite awhile
I suppose the primary obstacle of such thought is that it is EXTREMELY hard to stay objective under such considerings, as many things are rather personal ... given that we all ARE humans, and so forth.
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Still, assuming speciation, neither of the populations will remain as we are today, but will become different on their own terms.
Which gives the consideration ... assuming we don't speciate, and instead remain all the same species (and the same breed) ... will we remain as we are today? Or will we inevitably become something different?
Will the standard deviation of traits simply expand, while the mean stays the same? Or will the mean shift altogether?
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I suppose my main focus on this thought experiment would be to try and ignore Extinction events or Apocalyptic events because I think it would be far more interesting to see the simple effect of "TIME" on a species, and if there is any effect. Or if only a true change in the status-quo can cause a sort of evolution.
I mean it would be simple to say "Sun radiation killed all that did not upload themselves onto robotic software" or something silly, and I think transcendence is a similar cop out "all those that did not transcend were ...". Actually, all transcendence stories seem to entail the entire species Transcending, or even there being some religious plot for the rest that did not transcend.
But I am not talking about about becoming robots or transcending, but the pure biological fate for humanity as a species over the course of time.
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I think there are two ways of looking at this ...
1. that humanity will fundamentally change long before FTL becomes accessible.
and
2. that humanity will miraculously stumble upon FTL, and will be able to actively colonize other planets, and perhaps be able to interact with other sentient life.
as part of #2, there are two ways of looking at this as well
A. Humanity will find other sentient species and interact with them in a similar fashion as Star Trek et al.
B. That humanity will find no other sentient species.
And B is separated into 2 more parts as well
1B. We have complete access to FTL travel, and all of humanity will be on the same boat ... which brings us back to #1!!
2B. We have limited access to FTL, and speciation ultimately occurs. If FTL eventually becomes commonplace ... then you will have the "Star Trek" scenario, but every species would have originated as 'human', and equally none will be 'original human' any more.
Personally I think #1 is the most interesting to think about ... as we already have a ton of popular literature on #2.
While concept 2B is also interesting to consider .... (especially if one can argue that travel outside of our galaxy would be rather difficult, and under the assumption that other recognizable sentience would be unlikely to exist within the same galaxy)