For a much deeper treatment of this subject, I recommend Global Catastrophic Risks, edited by Nick Bostrom and Milan Ćirković. The overarching point is straightforward (see the paragraph above), but the details of each threat are interesting on their own.
1. http://www.amazon.com/Global-Catastrophic-Risks-Nick-Bostrom...
I suspect that our descendants 1,000,000 years from now wouldn't consider themselves Homo sapiens- primitive, brutish creatures. (Consider how we feel about our ancestors from as recently as 50,000 years ago.)
The threat of human driven human extinction is more on the lines of a mutually assured destruction, weaponized nanotechnology or genetic engineering, irreversible climate conditions, over population of the planet etc.
Are these people all completely ignorant of evolution and science? No matter what happens in the future, one or another species-obliterating risk is a certainty. Here's why:
1. Our species has existed for about 200,000 years.
2. On that basis, and given our present knowledge of biology and evolution by natural selection, it's reasonable to assume that, within another 200,000 years, we will have been replaced by another species who either successfully competed with us, or into whom we simply evolved over time.
3. Human beings are a note, perhaps a measure, in a natural symphony. We're not the symphony, and we're certainly not the reason the music exists.
4. Based on the above estimate, there will be 10,000 more human generations, after which our successors will no longer resemble modern humans, in the same way that our ancestors from 200,000 years ago did not resemble us.
5. We need to get over ourselves -- our lives are a gift, not a mandate.
6. I plan to enjoy my gift, and not take myself too seriously. How about you?
2. On that basis, and given our present knowledge of biology and evolution by natural selection, it's reasonable to assume that, within another 200,000 years, we will have been replaced by another species who either successfully competed with us, or into whom we simply evolved over time. "
When our species had existed for around 5 years, does that mean it was reasonable to assume that within another 5 years, we will have been replaced by another species?
You're missing the point that our species didn't arrive that quickly. From the perspective of 199,995 years ago, assuming a certain amount of intelligence, our forebears would make a similar assessment -- that they had assumed their present form some hundreds of thousands of years ago. And we have copious fossil records to support the idea of a typical duration for individual species before they disappear.
In any case, it doesn't matter which numbers one chooses within wide limits -- the fact is that our species will disappear, no matter what we do, within, say, 500,000 years at the most -- meaning our descendants will not be recognizable to use, could not interbreed with us, and would not be obvious kindred spirits to us.
We're a transient species, and we're not in charge, nature is.
The answer is evolution is more like a fork/branch than modifications on the trunk. Mutations happen all the time, every cancer victim, is a victim of mutation. But when the gene begins to spread and take root rapidly, at some point we get that gene dominant among a species.
A lot will happen over the next 200,000 years. We will likely change in major ways.
But if you were to take this whole singularity thing seriously we may not even need all that. By 2045 you can live on eternally on the cloud.
This is serious business. If we don't fill the entire universe with efficient replicators to speed up the consumption of all energy to equilibrium. Then the reason the universe was created will have been for nothing. The stars must not be allowed to run down without our first harvesting them for our multitude of shenanigans.
I hate to break this to you, but evolution isn't about humans or dolphins or spacefarers, it's about genes -- evolution is genes replicating, using organisms as vessels.
In answer to the old question about which came first, the chicken or the egg, an evolutionary scientist answers, "a chicken is an egg's way to make another egg."
Also, at a more mundane level, by the time our descendants are scattered across all the local star systems, they will be so different from us that we won't recognize them or feel any special kinship.
But on reading your post to the end, I see you're probably kidding. Oh, well.
The whole universe was created for nothing. No one cast a magical spell for it to come to being. Nothing that is happening is happening for a reason.
Its just some laws of physics at play.
We came to be only through some minute chance.
So. I believe one of the reasons humankind is so awesome is that we have the capacity to be more than just a note in your natural symphony; we are constantly changing, creating and inventing— and I think it's entirely up to us whether we continue to flourish. Not to get all mystical, but perhaps in time the notion that we are 'the reason the music exists' will not seem super far-fetched. I guess I just think that human consciousness is so unique and cool that it is worth going to great lengths to preserve it, and to hell with what's considered 'natural'.
Yes, that's true, but my point isn't a scientific one, it's a mathematical one. Given enough time, the human species will disappear. It's an equation, not a theory open to empirical test -- but it's certainly supported by evidence from other species.
> ... and I think it's entirely up to us whether we continue to flourish.
This denies a role for nature, from which we sprang. Given that, if we "thrive" and are not outcompeted by some other species, then instead the form of our thriving will be to evolve to the point where present-day people wouldn't be able to recognize the outcome as human.
I say this based on the copious evidence buried in layers of rock that records billions of years of evolution of countless species, of which we are one.
> I guess I just think that human consciousness is so unique and cool that it is worth going to great lengths to preserve it, and to hell with what's considered 'natural'.
More New Age fantasy. When we try to improve on nature, because of our intellectual limitations we instead become nature's obedient servants.
Mostly. Talk to your local mayor, deputy, senator, etc and you will see that these people live in worlds very different from ours.
Nothing is going to replace humanity if we kill ourselves first. Gradual evolution isn't want these people are talking about anyways, and there is no reason evolution is inevitable. Soon we will have the technology to control DNA however we want.
However, if (when) super-intelligent artificial general intelligence "arrives", that pretty much makes normal unaugmented humans the relative equivalent of chimps. It means that our opinions and actions are no longer historically relevant. We will be, relatively speaking, obsolete mentally disabled people running along doing relatively stupid things. http://www.youtube.com/watch?v=I_Juh7Xh_70
In order for our opinions and abilities to actually matter relative to the super-doings and super-thoughts of the new AIs, we really _must_ have this magical nano-dust or something that integrates our existing homo sapien 1.0 brains with some type of artificial super-intelligence.
So that is what I am worried about -- will the super-AIs show up before the high bandwidth nano-BCIs (brain-computer interfaces) or before I can afford them.
Of course, in the long run there may not be a good reason for AIs to use regular human bodies/brains at all and so that may be phased out for subsequent generations.
There are a lot of things to this Armageddon-through-AI equation. Firstly this thing called 'energy'. A paper clip maximizer will long reach its demise before converting a maximum part of planet to paper clips, merely because it needs a lot of resources to produce energy, and maintain itself too.
In fact true AI would not destroy anything. Because true AI would know it doesn't have sufficient data to make any such decisions.
For example, through a technological singularity or even just through accumulated gene therapy over generations.
That's getting a bit speculative as a question though. It was more of a thought on how much/how little we might need to change to even constitute not being human.
Of course we should also wonder what we may become as we rise. We are no longer the foragers who began this climb, nor the farmers who climbed just a few floors below, and those ancestors would probably not be pleased with everything we have become. We’ll probably also have misgivings about what our descendants become. But hopefully we will on net be proud of them, just as our ancestors would probably be proud of us.
And that is that evolution is not necessarily a progression from less to more advanced, from less intelligent to more intelligent, or for that matter, from less anything to more anything.
Evolution is not a plan with a goal, it is a blind algorithm that chooses survivors, regardless of the survivors' traits, with the single requirement that they are the fittest for the environment in which they find themselves.
This talk about steps up the ladder and extremely advanced descendants is scientifically ignorant and a New Age fantasy. We are as likely to be replaced by cockroaches as by superbeings.
Easily answered: our species has existed for about 200,000 years. Based on that, and barring any speed-up in the rate of evolution by selection (natural or unnatural), we will have been replaced by another species in another 200,000 years. This will happen no matter what else happens -- assuming we're not subject to any global catastrophe, but simply evolve as a species into something we cannot presently imagine.
This is very, very likely, and there's even concrete evidence, based on the fact that the human race was nearly wiped out 70,000 years ago, but recovered.
70,000 years ago a huge volcanic eruption with global consequences called the "Toba event" reduced the human population to somewhere between 3,000 - 10,000 people. We know this by analysis of our DNA, which carries a lot of information that can be used to assess our genetic history. That record shows that a severe genetic bottleneck took place 70,000 years ago, and geographic evidence shows a corresponding massive volcanic event thought to be responsible. More here:
