In the short term yes and I wouldn't expect Mars colonization to have an impact on our the survival of our species for at least 100 years. But in the very long run the sun isn't going to last forever and if resource exhaustion turns out to be a real problem there might only be a limited window for us to get started.
> But in the very long run the sun isn't going to last forever and if resource exhaustion turns out to be a real problem there might only be a limited window for us to get started.
I can't believe I'm still hearing "sun isn't going to last forever" and "us" juxtaposed, as though one had any bearing on the other.
1. Humans have existed as a distinct species for about 200,000 years.
2. Given the process of natural selection, in another 200,000 years we will have been replaced by something different than us -- not necessarily bigger or smaller, smarter or dumber, just different.
3. In a million years, there will be nothing remotely resembling human beings -- it will be as though we had never existed. But let's argue that there's some hint of us after a million years:
4. The sun will become a red giant and envelop the earth in somewhere north of five billion years, which is five thousand times longer than we can possibly exist as an identifiably distinct species, using the optimistic forecast of item (4) above.
We need to have some perspective about our relationship with nature. Evolution teaches us that we're not at all exceptional, but are a random answer to nature's constantly changing question, which is "who is fit today?"
This idea that we're somehow ordained inheritors of the planet, is to me a 21st century leftover of the religious outlook, which is that humans aren't just another species, competing in an open-ended contest with no entry requirements or registration fees.
Here today, gone tomorrow. We're not special, and life is not an ordained right, but a gift. I intend to appreciate my unearned gift. How about you?
> 2. Given the process of natural selection, in another 200,000 years we will have been replaced by something different than us -- not necessarily bigger or smaller, smarter or dumber, just different.
In the very, very long run, who knows.
But int the timescale of tens or even hundreds of thousands of years I don't think there will be any natural selection process that will apply to the current status of humanity as a species, unless for some reason civilization will fall and humans are scattered throughout the globe.
We've pretty much stopped evolving as a species through natural selection events. There's not much of that happening in the homogenized urban setting where the majority of people live, and will live for the foreseeable future.
Actually, having the current civilization as a substrate for the species does change the playing field considerably from what it was a few thousand years ago.
As for biodiversity creating some sort of 'better adapted species' to take over our position - the sad truth is that biodiversity is in rapid decline, and I don't know when it will stop. We are not killing the planet per se, only... homogenizing it and making it fit for humans.
In a million years, sure, who knows what will happen. But in the current mass extinction event - if we can feed the the human species it's very difficult for me to imagine anything will replace us when the timescale is only the current estimated age of the species.
Prepare to be rickrolled for the next 100k years. Or maybe we will move into some dense compute substrate made of exotic materials.
> We've pretty much stopped evolving as a species through natural selection events.
This is quite false. All that has happened is that we've (to some extent) replaced genes with memes, and memes evolve just like genes do.
Evolution is still underway, actively and blindly selecting individuals and ideas with equal efficiency.
> There's not much of that happening in the homogenized urban setting where the majority of people live, and will live for the foreseeable future.
I'll just give one example that falsifies the thesis -- what is called Asperger Syndrome (AS). A thousand years ago, someone having the behaviors associated with AS might be at a significant evolutionary disadvantage compared to someone who could pick more olives up off the ground. But today, the AS behaviors represent a distinct advantage because the environment has changed in ways that favor that mental wiring, such that a number of AS "sufferers" (to use the psychological terminology) are famous -- Bill Gates, Albert Einstein, Thomas Jefferson and many others identified as having AS.
AS is so obviously an advantage in modern times that another psychological school of thought called "Grit" goes so far as to describe the same behavior pattern as an advantage:
Of course, the Grit people don't call it AS or even mention AS, they just say how advantageous it is to have the intense focus and obsession with only a few activities (or even one) this behavior produces in many modern success stories.
It's evolution at work. I'm sure many more examples could be found, less dramatic than this one.
Evolution is the central theory of biology, and it didn't just stop for human beings when we built the first TV set or began dwelling in arenas of pure thought -- quite the contrary.
Success in the way you describe it has nothing to do with evolution. To choose someone at random - Sarah Palin is almost twice as successful as Gates or Einstein (she's had 5 children - those two only 3 each).
Unless people with AS / Grit have more children than those without, there's no selective pressure to increase the prevalence of the trait in the population. You could consider health of the children - so maybe you should count great-grandchildren rather than direct children.
BUT - I agree that evolution probably hasn't stopped - it just is selecting for different traits than it did 15,000 years ago. What exactly is being selected for in US in 2014, I can't say.
Actually, we have _not_ stopped evolving because of natural selection. A significant proportion of people choose not to have kids nowadays, or are just having one child.
In a generation or five all this "I don't want kids because there are too many of us in this planet already" crap will be over, and we'll only have people left (in developed countries) that get drunk and don't use condoms and decide to have the kids anyway, people prone to religious belief systems that forbid contraception, and just people that plain have very strong ingrained urge to have a family/kids, despite career pressures and all the information/stimulus overload from internets and 24h connectivity and all.
I'm actually using a very inclusive sense of 'us' here, meaning any sort of life. I'd prefer intelligent life that I can emphasize with, but I'll take what I can get.
Humanity isn't that special and I'm sure intelligent life would arise again without us, but now that Earth has developed fungi that can digest cellulose Earth is never going to have this much fossil fuel sitting around again. Maybe that doesn't matter and humanity or some other species will colonize space anyways... but maybe it does.
> I'm actually using a very inclusive sense of 'us' here, meaning any sort of life.
Okay, fair enough, that's reasonable -- so once we detect any sort of extraterrestrial life, then we can forget about leaving the planet. After all, there's life everywhere, so our leaving Earth loses its significance.
I think we'll colonize Mars for the adventure, or to satisfy our curiosity, not as a first step in colonizing the universe. The latter might be what we'll say, but it won't be the real reason.
However, humanity lives in an increasingly global environment, and natural selection works slowly - so no two generations will be able to draw a line saying "they're a different species," so they'll still likely call themselves human. And they'd still be our descendants, so I don't know why we wouldn't still think of them as "us" in some way. I don't see a split in what is considered "human" unless we do become an interplanetary civilization, because then it's conceivable that groups of humans could be removed from contact with the rest of humans, and end up evolving in a different direction. Though I wonder how much convergence there would be anyway, given that we save people from a lot of things that could keep them from passing on their genes. I think there will be a wide range in what is considered "human."
> However, humanity lives in an increasingly global environment, and natural selection works slowly - so no two generations will be able to draw a line saying "they're a different species,"
True, but what makes a species a species remains the same. Eventually our descendants wouldn't be able to mate with us (or would want to), and that perspective will mark the end of the human species.
> I think there will be a wide range in what is considered "human."
> 1. Humans have existed as a distinct species for about 200,000 years.
No, that's wrong. Humans, genus Homo, have existed for about 2.5 million years; the subspecies H. sapiens sapiens for about 200,000. The species H. sapiens is a little less clear, there's debate over whether it starts around 200,000 years ago (and includes just a few subspecies, notably H. sapiens sapiens and H. sapiens idaltu) or whether it starts around 500,000 years ago and includes several others.
> 2. Given the process of natural selection, in another 200,000 years we will have been replaced by something different than us -- not necessarily bigger or smaller, smarter or dumber, just different.
Unlikely; while speciation requires time, time alone is not generally enough, and even if it were, there is no reason to expect the time from the last speciation event to now (whether 500,000 years or 200,000)
to be the time from now to the next speciation event.
(Colonization of Mars -- if Earth-Mars interaction is limited once the colony is established -- might actually accelerate that, since the one thing that does contribute to speciation is geographical separation which prevents significant interbreeding between segments of the wider population.)
> 3. In a million years, there will be nothing remotely resembling human beings -- it will be as though we had never existed.
Human beings, genus Homo, have been around for two and half million years already, and H. sapiens (whether you take the narrower or broader view of the species) would be a flash-in-the-pan as species of its size, lifespan, and geographic range are concerned if it wasn't around for several million more (H. erectus -- with competing members of the genus Homo around on Earth for pretty much its whole time of existence -- lasted about 1.75 million years), and things "remotely resembling human beings" have been around significantly longer -- and can be expected to be around significantly longer than humans in the strict sense, unless humans are wiped out completely in a cataclysm rather than subjected to the kind of pressures that produce speciation.
> The sun will become a red giant and envelop the earth in somewhere north of five billion years, which is five thousand times longer than we can possibly exist as an identifiably distinct species, using the optimistic forecast of item (4) above.
The million year forecast isn't "optimistic"; while it may be unlikely that human beings would be around for 5 billion years, your particular argument for that point is, well, based on one controversial claim and a couple of unjustified claims that don't follow from that controversial claim.
> The million year forecast isn't "optimistic"; while it may be unlikely that human beings would be around for 5 billion years, your particular argument for that point is, well, based on one controversial claim and a couple of unjustified claims that don't follow from that controversial claim.
Where's the refutation of my point that we will have entirely disappeared in a million years, replaced by some other species? This isn't a philosophy debate, where words like "controversial" and "unjustified" carry weight among people trained in critical thought.
> Where's the refutation of my point that we will have entirely disappeared in a million years
Where's the support for the claim?
> This isn't a philosophy debate, where words like "controversial" and "unjustified" carry weight among people trained in critical thought.
"Unjustified" always carries weight among people trained in critical thought, at least, when its true -- i.e., no adequate support has been provided for the conclusion presented. You've simply asserted that humans have been around for only 200,000 years as a species (which is one of two common viewpoints about H. sapiens, though "humans" in this context usually means the genus Homo and not the species H. sapiens -- 500,000 is the other, because where exactly at what point H. sapiens becomes a distinct species is debated), and jumped from there to the conclusion that H. sapiens will be replaced in another 200,000 years and that nothing similar will be around in a million years. Neither of those conclusions follow from the premise, which itself is less-than-certainly correct.
The expression "begging the question" doesn't mean what you think it does.
> I wonder what you have to be, to be special according to the flavor of meaning you just happen to prefer?
The answer is obvious -- no particular form of life is special or supernatural. It's all part of natural selection, changing species adapting to a changing environment. And this isn't just some hypothesis, it's the central idea in evolution, a very well-supported scientific theory.
And our "flavor of meaning" has no part to play, only objective evidence, the evidence that overwhelmingly supports the theory of evolution.
That's not sure at all - there's no telling how far technology will take us. Eventually, we might be able to forge entirely new universes, or to move to younger ones.
(completely unrelated, but I'm getting tired of creating throwaway accounts on this site each time I want to post a new comment - why oh why is anonymous commenting disabled ?)
Because Hacker News wants people to stand behind their comments. Lack of accountability is not a desirable feature if you're trying to encourage civilized discussion.
If we can't get our shit together in the billions of years it'll take the sun to sputter out, we don't deserve to live.
Honestly, are you really going to be disappointed if, after a few billion years, humanity runs out of gas? We'd have done be the most successful species in the history of species.
> Honestly, are you really going to be disappointed if, after a few billion years, humanity runs out of gas?
What? Humanity will have entirely disappeared in a million years, and in a billion years we won't even be a distant memory.
Please try to remember that we've only been a distinct species for 200,000 years, and in another 200,000 years, chances are we will have been replaced by something different. In a million years, five times as long, we will not exist in any form whatsoever. In a billion years, five thousand times as long, creatures who have forgotten about us will themselves be forgotten.
It is the height of absurdity to think that a lowly species like us will exist in any form at all even a million years hence. Both us, and all our stellar achievements (like Country & Western music and the Pet Rock), will have completely disappeared.
> Humanity will have entirely disappeared in a million years
Even if you mean that in the narrow sense of H. sapiens, rather than humans as genus Homo, that would make H. sapiens a shorter-lived species that H. erectus. If there's a reason to believe that, you haven't provided it.
> Please try to remember that we've only been a distinct species for 200,000 years
Or 500,000, depending on which view of the relevant taxonomy you take...
> and in another 200,000 years, chances are we will have been replaced by something different.
There is no factual basis for this claim; particularly, even if we except your POV on how long we have been around so far as a species, it does not follow that the same amount of time in the future would see us replaced.
> In a million years, five times as long, we will not exist in any form whatsoever.
Again, you provide no reason to believe this. H. erectus was around for 1.75 million years. If H. sapiens only lasts as long as H. erectus did, our species would be around -- starting from your 200kYa start date for H. sapiens, another 1.5+ million years. And humans, genus Homo, have been around for over 2.5 million years.
> It is the height of absurdity to think that a lowly species like us will exist in any form at all even a million years hence.
It really is not. We may be lowly, but a species lasting a mere 1.2-1.5 million years (what H. sapiens would have to last in total to be around a million years hence) is not uncommon at all. Many hominid species have, why wouldn't H. sapiens?
>> It is the height of absurdity to think that a lowly species like us will exist in any form at all even a million years hence.
> It really is not.
You, too, can learn evolution by natural selection and such related disciplines as probability. We could not successfully mate with our forebears from a million years ago, and chances are we will not be able to mate with our descendants a million years hence.
>> and in another 200,000 years, chances are we will have been replaced by something different.
> There is no factual basis for this claim;
What? There is no "factual basis" for my saying "chances are"? I didn't make a statement about fact, I made a statement about probability, and a very good one.
In any case, were you not more interested in generating heat than light, the point I successfully made was that five billion years from now, there will be no sign of us to fret over the earth's being absorbed by the red giant star our sun will have become. You know, before you tried to change the subject?
> What? There is no "factual basis" for my saying "chances are"?
Correct. Exactly.
> I didn't make a statement about fact, I made a statement about probability
Claims about probability still require factual support (and, in fact, are still fact claims -- that, given given particular prior conditions, there exists an X% probability of a particular subsequent event is a fact claim, even if it is a different fact claim than the claim that the subsequent event is certain.)
> the point I successfully made was that five billion years from now, there will be no sign of us to fret over the earth's being absorbed by the red giant star our sun will have become.
There may be a reasonable basis for that conclusion, but if there is, you haven't presented it, so it would be inaccurate to claim that you have successfully made that point, even if it is a point that could have been succesfully made.
>> What? There is no "factual basis" for my saying "chances are"?
> Correct. Exactly.
Honest to God. A statement of probability is not a fact, it is an estimate. You aren't even familiar with the terminology.
> Claims about probability still require factual support ...
False -- they require evidentiary support. A probability estimate requires a basis for making the estimate, which I provided. If you had any understanding of either science or statistics, you would be familiar with what I'm talking about.
Here's the evidence:
1. There are no species that were present on Earth a billion years ago that are still present in the same form, i.e. able to interbreed with their forebears.
2. There are few species that meet the above requirements from 100 million years ago.
3. There are a handful of species that meet the above requirements from 10 million years ago.
4. Modern humans have existed only for 200,000 years.
5. Using the simplest statistical methods, accessible to an average college student, we can write a distribution that takes into account the fact that modern humans didn't exist 200,000 years ago and extrapolate into the future, showing that our likelihood for existing as the same species we are now, 200,000 years in the future, is very small. This is a statement about probability and likelihood, areas with which you are clearly unfamiliar.
6. On the above basis, the probability that modern humans will exist as the same species a billion years from now is zero.
7. On that basis, the probability that modern humans will witness the sun enveloping the earth five billion years from now is also zero.
If you can't understand the above argument, by all means keep your ignorance to yourself.
> There may be a reasonable basis for that conclusion, but if there is, you haven't presented it, so it would be inaccurate to claim that you have successfully made that point, even if it is a point that could have been succesfully made.
Look -- go back to the philosophy department, where contentless arguments like yours, arguments indistinguishable from two children negating each other, are welcome.
In your fantasy, modern humans, which didn't exist 200,000 years ago, have some chance to be present to worry about the sun absorbing the earth five billion years from now. And you think my probabilistic estimates are doubtful. The burden of evidence is yours, not mine.
EDIT: Yes, people, don't bother to read the argument, the evidence, just click the downvote button. Live up to my expectations.
> There are no species that were present on Earth a billion years ago that are still present in the same form, i.e. able to interbreed with their forebears.
That's not really a useful basis for conclusions about the outer limits for either species in general or any particular species, as sexual reproduction itself may only be around 1 billion years old (from what I can tell, that's the age of the oldest fossil evidence), but, in any case, the oldest animal species seems to be around a 445 million years old, which is a sizable fraction of the time that multicellular life has existed on earth.
> Using the simplest statistical methods, accessible to an average college student, we can write a distribution that takes into account the fact that modern humans didn't exist 200,000 years ago and extrapolate into the future, showing that our likelihood for existing as the same species we are now, 200,000 years in the future, is very small.
No, you can't, because none of the facts that you cite would support any calculation that would lead to that conclusion. If you assume that species total lifespans are randomly distributed (a dubious assumption), and you make the further assumptions that the lifespans evident from the fossil record accurately represent the full lifespans of species (also dubious), you could calculate a distribution function for the actuarial expected future lifespan of a species given how long it has existed previously. But even if the necessary assumptions weren't problematic, none of the premises you cite (alone or together) would support the conclusion that "modern humans", being around 200,000 (even assuming that "modern humans" are even a species and not just a subgroup within a species, which is an actively disputed point) would, as a species, only be around another 200,000 years.
> On the above basis, the probability that modern humans will exist as the same species a billion years from now is zero.
This further conclusion -- and the following one -- fails to be supported because it rests on the prior failed conclusions.
> If you can't understand the above argument
I understand it -- its a stream of statements that you assert follow from each other that don't.
> In your fantasy, modern humans, which didn't exist 200,000 years ago, have some chance to be present to worry about the sun absorbing the earth five billion years from now.
No, I haven't made any positive claim about the likelihood of that happening. You've made a claim about it, but its a claim that rests on dubious stated premises, and, on top of that, doesn't even follow from those premises.
>> There are no species that were present on Earth a billion years ago that are still present in the same form, i.e. able to interbreed with their forebears.
> That's not really a useful basis for conclusions about the outer limits for either species in general or any particular species, as sexual reproduction itself may only be around 1 billion years old (from what I can tell, that's the age of the oldest fossil evidence), but, in any case, the oldest animal species seems to be around a 445 million years old, which is a sizable fraction of the time that multicellular life has existed on earth.
First, you have simply confirmed what I said above, while simultaneously attempting to deny its evidentiary basis.
Second, let me explain something to you, something you very clearly do not understand. You are trolling. You have nothing constructive to offer this discussion, you offer no evidence or productive arguments of your own, and you are constantly restating the terms of the argument to suit yourself. If I offer a guess about the future based on statistical probability, you reinterpret that clearly stated guess as a statement of fact about the future, and call it false. But in point of fact, probabilistic guesses about the future are neither true nor false.
You have yet to argue against what I have actually said -- instead you argue against a series of straw men of your own fabrication.
Stop trolling -- it's not constructive, it's a waste of time, and it makes you look inexperienced and narcissistic.
I don't find lutusp's points to be all that unreasonable. While you passionately assert that they're false or poorly reasoned, I really haven't been able to figure out from your post what you think the exact problem is.
If there's not a single species present today which was also present 1B years ago, it does not seem unreasonable to me to suppose that humans will not be around in five times that timespan in the future. If anything, this should be the default supposition, and it is any claim to the contrary -- that we will be around in 5B years, in a form we could mate with -- which needs extra support.
