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Are Intelligent Civilizations Doomed?

One answer to the Fermi Paradox is the idea of the Great Filter; the possibility that something wipes out 100% of intelligent civilizations. That why we’ve never discovered any aliens… they’re all dead. Is that our future too?

In a previous episode, I presented the idea of the Fermi Paradox. If space is huge, like space huge, not aircraft carrier huge, and there are billions upon billions of stars, AND there seem to be lots of habitable planets around those stars, where are all the damn aliens?

There are plenty of theories about what might be the solution for the Fermi Paradox, like there aren’t a lot of aliens out there and we’re too far apart to bother with, or maybe they just don’t want to talk to us because of our meat cooties, or maybe we’re really in a cosmic zoo and if you break it, you bought it.

It’s possible that we’re the first intelligent civilization to exist in the entire Universe, but I’ve never been a fan of that idea. If we’re the best the universe can do in billions of years, I seriously need to make some heavy expectation adjustments to my view of everything.

Planets everywhere. So where are the aliens? Credit: ESO M. Kornmesser

Planets exist everywhere. So where are the aliens? Credit: ESO M. Kornmesser

There is still another theory, one that you might find troubling. It’s called the Great Filter, and it says that something prevents intelligent civilizations from ever forming, in a darkly mysterious Philip K Dick kind of way.

Consider the long series of steps that happened to get from the early Earth to where we are now: A planet with the right combination of atoms needed to have liquid water long enough for organic molecules to form, those molecules needed to somehow be able to reproduce, eventually becoming the first organisms, which became multicellular organisms, then learning to reproduce sexually, evolving tool use, and eventually becoming intelligent life, and all the while managing to survive a planetary extinction or two. And then, at some point in the future, this intelligent life goes on to colonize an entire nearby galaxy.

Since humanity has passed all those previous steps, we know they’re not impossible. Maybe really really improbable, but not impossible. As we imagine the future, there’s nothing in the laws of physics that’ll stop us from building machines that can help us colonize the entire galaxy. Pretty machines with blinking lights, possibly incorporating meat parts from future generations of humans. If we can do it, any race could do it.

If the universe has been around for 14 billion years, and we’ve done it in a fraction of that, there’s been plenty of time for this to have been done. And yet, still no aliens. So maybe the Great Filter is still waiting for us. No matter how hard we try to extend beyond our Solar System, something will stop us.

This image shows the Hubble Ultra Deep Field 2012, an improved version of the Hubble Ultra Deep Field image featuring additional observation time. The new data have revealed for the first time a population of distant galaxies at redshifts between 9 and 12, including the most distant object observed to date. These galaxies will require confirmation using spectroscopy by the forthcoming NASA/ESA/CSA James Webb Space Telescope before they are considered to be fully confirmed.

There are so many places where aliens could have evolved. So where are they? Credit: NASA/HST

So what could the Great Filter be? There are lots of ideas. Maybe all civilizations discover the most horrible of weapons and eventually destroy themselves. They could develop virtual reality technology and choose to spend their future in a simulated reality. They could create an exotic type of matter that destroys their home planet. Perhaps they create robotic servants who inevitably overthrow their masters in a planetary robotalypse. Perhaps someone creates a super plague that wipes out all life, the civilization ruins their environment and its ability to support life by filling their oceans with plastic and their atmosphere with CO2 until their planet becomes a pressure cooker. Or maybe they just watch too much reality tv and just get too dumb to put food in their own mouths and die of stupid.

Whatever the cause is, here’s the haunting idea behind it… Whatever this Great Filter is, it must hit 100% of intelligent civilizations. Because if even 1% of aliens are able to avoid it, they’d go on to colonize the galaxy. And still even to this day, yes, we have no aliens.

There could be some high probability absolute devastation event in our future, which will happen just before we become a space-faring civilization…. And there’s no way we can predict or prevent it. The idea that all advanced civilizations are doomed is unsettling.

Here’s hoping that the Great Filter is wrong. Either we’re the first advanced civilization in the Milky Way, or perhaps we’ll figure it out, and avoid the catastrophe that killed off all the other aliens in the galaxy.

So what do you think? What’s it gonna be? What will wipe us out? Tell us in the comments below.

About 

Fraser Cain is the publisher of Universe Today. He's also the co-host of Astronomy Cast with Dr. Pamela Gay.

Comments on this entry are closed.

  • FarAwayLongAgo August 25, 2014, 12:33 PM

    We haven’t had a close look out for alien civilizations yet. But in a few decades we will have. And if the result still is zero, this question gets more important.

    It is a great point that even only one single uninterrupted civilization on a similar trend as we are on, would be enough to colonize the entire galaxy within a small fraction of its history. The Sun has orbited it about 15 times, it’s been all over the place and had thousands of different stars as its nearest neighbors. And I love the expression I’ve never heard before: “OTHER” aliens…

    Maybe it is the fear of the filter that is the filter and scares everyone from trying new things?

  • Pedro Gonzalez August 25, 2014, 1:38 PM

    The viruses win. After trillions of generations, and trillions and trillions of individual dead viruses, a lethal virus that is immune to all drugs evolves and kills all the intelligent beings.

    • FarAwayLongAgo August 25, 2014, 2:55 PM

      That’s why Mars and Venus are dead. They are infected by the anti life virus. When we bring back samples from Mars, all life on Earth will be reduced to dust too. That’s the filter.

      No, I don’t believe that!
      Mars bugs are welcome to have a fight with my immune system any day, we’ll kill them, make food out of them and fart what remains of them. The bad guys are those which have lived and evolved together with us for billions of years. They have figured out some of our weak spots. But a new guy on the block won’t stand a chance. Has no clue what it is dealing with. We are experts on surviving. My CV goes four billions years back, and I and my ancestors have tried out most things imaginable. I had a cousin of a cousin or so who actually went to the Moon and came back alive and told us about it. I bet no Mars bug has done that.

  • Homonymous Anonymous August 25, 2014, 2:00 PM

    Stupidity will wipe us all.
    But it will take many forms and hit like a perfect storm.

    1-Overpopulation
    2-Blinding plutocratic selfishness and greed
    3-Natural ressources depletion
    4-Worldwide and irreversible economic collapse
    5-Climate change
    6-Civilization collapse
    7-Natural or man-made depopulation (war, famine, virus…)
    8-Technological and scientific regression
    9-Chaos
    10-Return to everlasting feudal political system
    11-Lack or remaining ressources to recover to previous state of knowledge and prosperity. Therefore, no space colonization.

    People must understand all our present prosperity is only the result of oil, a cheap energy source. Without oil, everything crumbles.

    We are bright enough to start the fire but not enough to extinguish the fire.
    Those of us able to see the world on the long term are a tiny minority. So even if a few of us scream like hell to warn all the others, it’s not enough to turn the ship and avoid the iceberg.

    That it for humans and that will be OUR filter.

    There is this concept in biology that says : For the same problem, the same solution. Think about wings to insect, dinosaurs, birds, mammals and even some fishes!

    Now for the aliens.
    Aliens will be submitted like us to darwinian evolution and the pressure of natural selection.
    Intelligence have to be a determining survival asset for a technological civilization and it is certainly submitted to competition for reproduction.
    High intelligence also can’t lead to high knowledge without a long education. And a long education means a lot of efforts invested from the «parents» and the «society». Therefore they might very well being valuing a kind of individuality, which likely means self-centered egos.
    So unless an alien civilization turns out to be the result of an ant-like social species (very unlikely but a really bad news for us on many levels for many reasons), it may very much lead to a civilization having a lot in common with ours. And that is a really bad news for them.

    An ant-like species might never get interested in space exploration and inter-species communication and might only respond [very aggressivelly] to provocative action.
    The other species similar to us might very well auto-destruct themselves in short term after getting to a technological level similar to ours for similar reasons.

    You’ve guessed it : I’m very not optimistic about our chances to contact aliens.

    • baileyredwood August 26, 2014, 11:30 AM

      Yes, H, I think you nailed it on the head! Well said, by the way (not only because I was thinking the same thing).

  • Richard Kirk August 25, 2014, 2:16 PM

    Nope. Don’t believe we are doomed.

    It is not unreasonable to believe on present evidence that (a) there is other life in our galaxy, but (b) we may have to search for a hundred thousand years before we find anything.

    I don’t think our present state of explosive growth and research is typical of million-year societies. But we can write stuff down and store it. I am not saying that there might not be some nasty times ahead for some of us if we make serious mistakes with climate or genetics, but the death of even 99.99% of mankind would leave us with plenty to re-build, and hopefully the good sense to keep our numbers down a bit next time. Or maybe, mankind replaces itself with something better. Dang it, we’ve only been writing for a few thousand years, and in space for sixty years or so – you can’t extrapolate from that.

  • geckzilla August 25, 2014, 2:59 PM

    I actually love the idea that we are the first technological beings, at least within our locality. It’s totally possible and I don’t think a lot of people give it much credence because it seems unbelievable, which is perfectly understandable. We shun the idea that we could be exceptional because of our cosmic perspective and because we once arrogantly thought we were at the center of everything, divinely gifted.

    Yet we have a data point of one. Who could judge how plausible or implausible it is with what is essentially 1 bit of information? Using Earth’s life as our only example, we can assume intelligence is unnecessary for evolutionary success but it is a prerequisite for technology. Intelligent life may be abundant (intelligence is abundant on Earth!) but it is important to distinguish it from the kind of intelligence required to use the scientific method and create technology.

    How many hundreds of thousands of years were our ancestors intelligent but failed, generation after generation, to concoct the scientific method? How tenuous was their existence? They could have easily vanished. The Great Filter could very well be contained in our own history.

    • FarAwayLongAgo August 25, 2014, 3:57 PM

      You should consider:

      1) That the Sun has done about 15 orbits around the galaxy. We aren’t “local”. The dinosaurs evolved on the opposite side of the Milky Way!

      2) Intelligence and civilization and interstellar space travel are all evolutionary helpful. They should help multiply their practitioners. Universially, not just here and now.

      But until we have evidence of anything else, I think we should act as if we are alone. It is quite possible that we are! We don’t know. Either way it is a miracle. (So I bitterly bet that we will never know, for ever wafting in darkness between the two possible miracles of being unique or having company).

  • Ronald August 26, 2014, 5:03 AM

    I utterly disagree with Homonymous Anonymous, no matter how modern, fashionable and politically correct this view may be. We will not do ourselves in completely as a result of any resource scarcity, population problem, or any environmental problem. We will always survive any of those.
    I think the reason for the Great Silence is very mundane: rarity, both spatial and temporal.
    Our Milky Way galaxy may be big in space and time, but it isn’t endless. Of the few hundred billion stars, according to recent guesstimates, there may be only a few hundred million in the Galactic Habitable Zone, with a habitable terrestrial planet in the Habitable Zone of a roughly solar type star.
    If some 10% of those have developed higher (Eukaryotic) cells, that leaves a few tens of millions of planets. Multicellular and higher life (specialized organs) developed late on Earth, under specially suitable conditions (in particular high oxygen levels and some other vital nutrients). If, say, this is the case on 10% of the previous subset, this leaves only a few million planets with higher life in our MW galaxy. Intelligence developed even later and is apparently not necessary for evolutionary success. If we assume some 1% of the previous subset, that leaves only a few tens of thousands of planets in our MW galaxy. High intelligence, technological civilization must be even much rarer and later. How many planets develop that? Maybe only 1% or 0.1% of the previous subset, leaving only some tens to a few hundred planets, spread over vast space and time. And undoubtedly (an unknown) part of those will go extinct before ever becoming space-faring. Two temporally overlapping civilizations may be a very small chance.
    Incredibly as it may sound, there may simply not have been enough planets and time in our MW galaxy for an interstellar civilization to develop. We may indeed be the first, no Paradox.
    PS: now, the Andromeda Galaxy may be an entirely different story. That galaxy is probably teeming with life and intelligence, but they are wise enough to avoid us ;-)

  • theNeverKings August 26, 2014, 5:08 AM

    CO2…or a lack of it!

    I was looking for info on paleo climates and happened upon some reconstructions of CO2 levels over the span of Earth’s history. I was initially surprised to note a long term downward trend that appeared to have begun accelerating approx. 100 million years ago. The modern, pre-industrial era CO2 levels would appear to be an all time low (~250-270ppm).

    What I found confronting was the fact that the majority of the more complex plants/trees require CO2 levels in excess of 150-170ppm to enable efficient photosynthesis. Below that threshold vegetation will start dying, although some plants such as certain grasses can apparently survive with as little as 3ppm.

    When historical CO2 values are taken in context, it can be seen that there’s not a great difference between pre-industrial CO2 levels and the point at which plant life starts running into trouble. Of course, once the more complex vegetation starts dying, it doesn’t bode well for the rest of us!

    The idea that occurs to me is that since Carbon based life is, strangely enough, dependant on the supply of Carbon available to it, any reduction in the amount of available Carbon can ultimately effect the ability of (complex) life to survive. To the best of my admittedly very limited knowledge, CO2 is the main (only?) source of Carbon available to the Carbon based life on this planet.

    If the above idea holds true, the long term survival of Carbon based life on any planet is ultimately determined by the reserves of Carbon available to it. And IF that available Carbon is in the form of atmospheric CO2 and IF the Earth is a typical case then it can be seen that complex life and thus civilisation, only has a limited time available to it until the Carbon fuel tank/battery becomes effectively empty/depleted. This could go some way towards explaining the so called “Fermi Paradox” or “Where are all the aliens?”

    Of course, if my idea has any merit whatsoever, the current “war” on CO2 is somewhat ironic.

    Any thoughts?

  • Tihomir August 29, 2014, 5:58 PM

    I could agree with Ronald, except where he says “part of those will go extinct before ever becoming space-faring”. The whole subject of this article is “do (all) the aliens go extinct, and, if so, HOW?” and Ronald says many things but nothing about it.
    I don’t know about any aliens and if anything got them.
    For us, it would still take a looong time to conquer the Solar system, not even mentioning the galaxy! Before that happens, a valley around Old Faithful, called Yellowstone, is going to pop. After that, no more rockets, no more internet, no more cars. It’s back to the roots.
    Sooner or later, maybe even before Old Faithful, another event similar to Tunguska or Tschelyabinsk, but much heavier and more consequential, is also highly probable to happen, and that is going to be unpleasant (ask T-Rex).
    We may get to Mars before that, however.
    Whether the humans ever manage to become autonomous there (or on the Moon?), is the big unknown.

  • DPrime August 31, 2014, 7:24 PM

    I’d have to say that there is no Great Filter, and that the universe is teaming with life.
    Why haven’t we met anyone? Because there would be no point to talking to Humans at our current level. We can’t travel the stars. We have no trad-able products of value that could not be gained in other ways such as taking them and reproducing the product themselves. We are moderately violent, and our tastes in art fashion and philosophy are probably not of any interest.
    I think aliens would be crazy to make contact with the human race as a whole, maybe some individuals but doubtfully the whole planet, as there is nothing to gain and everything to lose.
    If I were a space faring species, I would either give us a wide berth until we are more palatable (maybe keep an eye on us out of morbid curiosity, unless that also has been done before and they have studied the growing pains of other civilisations), or wipe us out just to make sure we don’t go stirring up trouble when we do get our space legs (especially since a lot of our pop culture in regards to space travel involves leaving a trail of destruction and exploitation across the galaxy, not so unlike how we treat each other here on Earth).

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