The evolution of extraterrestrial life

This is the third or fourth video I’ve seen of Arvin Ash, and have been impressed with how level headed his thinking is.  (In other words, his biases seem to match up well with mine.)  This one on how alien life might evolve strikes me as right on the money.

(The first few minutes end up being an advertisement for Magellan TV.  It’s over around the 2:41 mark.)

Ash quotes Seth Shostak’s hypothesis that the intelligence we’re most likely to encounter would be machine life.  I think that’s right, although those machines might be be far more organic looking than our current ones.

As the video notes, evolution made life out of the most common elements lying around in the universe.  It strikes me that an advanced civilization would be able to utilize those most common elements for their machines.  And one which has mastered nanotechnology would probably produce machines that act a lot like life.  In other words, if we do encounter an alien intelligence, it might look a lot more like engineered life than what we think of as machines.

That said, per Fermi, I’m not holding my breath for such an encounter.  The Earth has been sitting here with an interesting biosphere for billions of years, with visible complex life for the last 600 million.  If there are alien civilizations sending probes out into the galaxy, we should have been discovered long ago, and the aliens (either as machines or engineered life) should have been here long before we evolved.

Maybe they are here, but hiding, either for a Star Trek style Prime Directive purpose, or for managing the zoo.  Or they could be here and out in the open, but we’re not able to recognize them.  An interesting exercise is to try to ponder what things we’ve always taken as natural that could conceivably be technological artifacts, as difficult for us to recognize as the significance of a fence is to a monkey.

It could be that they were once here but are now extinct, because civilizations all destroy themselves, apparently including their machine progeny.  Or it might turn out that interstellar exploration, even by machines, is so appallingly difficult or costly that no one bothers.

Or they might simply be too far away to have reached us yet.  That’s where my money is.  They may be so far away that we’ll never manage to encounter them before expansion of the universe separates us forever, or our machine progeny may someday encounter their machine progeny somewhere out in the universe, far from either of our places of origin.  (I’d say I hope I’m wrong about this, but I’m not sure that’s true.  It seems an act of faith to assume things would necessarily turn out well in such an encounter for the less developed civilization.)

In the meantime, I think Ash is right.  The type of alien life we’re most likely to encounter is microscopic and unicellular.  In that scenario, we’d probably be on the most developed side.  Probably.  (Remember the havoc a microscopic agent is currently causing in our world, not to mention the famous ending of War of the Worlds.)  Either way, I wonder how that will turn out for the less developed side.


39 thoughts on “The evolution of extraterrestrial life

  1. I don’t see why “one which has mastered nanotechnology would probably produce machines that act a lot like life.” Unless you mean act intelligently, in which case sure. Life is made out of sticky stuff that doesn’t conduct electricity or light well, and probably doesn’t survive high doses of radiation well. If you’re making space probes, seems to me you want something that can think quickly, and survive high radiation so you need less shielding on your ship.

    Liked by 1 person

    1. What I was thinking when I wrote that (and probably should have made explicit) is the machine would be tailored for the environment. So materials conducive for space would be used for machines travelling through space, but in a biosphere, the materials on hand would be used.


  2. “An interesting exercise is to try to ponder what things we’ve always taken as natural that could conceivably be technological artifacts, as difficult for us to recognize as the significance of a fence is to a monkey.”

    I’ve been thinking about writing something on ETs, UFOs, etc. Probably too much time on my hands and I’ve managed to drift into various, possibly dubious documentaries.

    Of course, most sightings, encounters are mistaken natural objects. Some are hoaxes. Some are people who really believe they are encountering something for whatever reason.

    One of the more interesting takes on the phenomenon is by Jacques Vallee Passport to Magonia. He goes back through history and compares it to fairy and elf sightings. Also, gives a deeper historical context, for example the mystery airship sightings in late 19th century.

    Vallee doesn’t think they are extraterrestrial but may be some other form of life.

    It all raises a key point. If there is something out there that is so beyond our experience that we would have no context into which to place it, then it might appear as fairies or elves to people a few hundred years ago or grays and ETs to people today.

    Liked by 1 person

    1. Very true. Before Sputnik it was, as you say, fairies, elves, ghosts, etc. After Sputnik it was UFOs. We pattern match according to what we know. (Notice how UFO and Big Foot sightings have dropped now that everyone carries a video camera?)

      Liked by 1 person

      1. The modern history of UFOs mostly begins with Kenneth Arnold’s sightings of saucers in the 1947. Explained as flocks of birds.

        The 50’s were very active.

        I don’t know whether UFO sightings have dropped in recent years.

        Take a look at the Wikipedia list for 21th century.

        Take a look at the Nimitz sightings with radar, video, and visual sightings.

        Or the Theordore Roosevelt sightings.

        Both explained mostly as equipment malfunctions.

        Rather bizarrely some one claims:

        To really be sure, we would need the raw data”, “visual displays alone are not the best evidence”


        1. For me it boils down to this: Probability of human brain being fooled into false pattern recognition: Extremely high. Probability of equipment malfunction: Fair. Given crop circles, let’s include: Probability of a hoax or joke: Not insignificant.

          Probability of aliens given the rigors and challenges of space travel: Extremely, even extraordinarily, low. I need to see some hard evidence.

          As an aside, I find even more extraordinary the idea that aliens have conquered space travel but then lurk in the bushes without revealing themselves, although, to that end… 🙂

          Liked by 1 person

          1. Crop circles: Some meteorological, most hoaxes

            Nimitz: Equipment malfunction? I don’t know, especially when there are visual sightings. Also, this is equipment we hope to use to defend ourselves. I would hope we would have most of the glitches removed from the system by software or the bogus images would quickly get recognized from what they are and nobody would pay them any attention. For the moment, I would just say there is no good explanation. Sometimes no answer is the best answer.

            Then there are the whole other classes of phenomena where something is sighted very close, sometimes by multiple people. Mass hallucinations? Perhaps there is something strange about the angle or light reflecting off it and imaginations of people feed off each other. Abductions. Hoaxes some. Others temporal lobe disorders? Some weird stuff without good explanation.

            Keep in mind that Jacques Vallee doesn’t think they are extraterrestrial.

            If aliens have conquered space travel, it’s probably impossible for us to imagine how they might act.


    2. That’s the problem with engaging in this type of exploration. We’re predisposed to see something extraordinary, extraterrestrial in contemporary times, or magical in the pre-scientific age. Most of what we see is going to have a natural or mundane explanation of some type. Indeed, we should assume it will until and unless the evidence forces the issue.

      And to Ash’s point about little green men, I think elves and fairies are too human in appearance to have any real chance of being from outside of our biosphere, or imagination.

      But when I made that comment, I was thinking more of something we don’t even think much about, that’s such a part of our world that we don’t take much account of it. Of course, I have no idea what that might be, but that’s the point.

      Liked by 1 person

      1. We might be predisposed to see this something (whatever it is, even if figment of our imagination) as human-like even if it is completely non-human. We’re going to put some interpretation on it if we see it at all.


  3. I’ve wondered if space is too challenging, too vast, and too time-consuming. Maybe intelligent species, if any arise, end up stuck in their own neighborhood. Even machines would have a tough time retaining complex function in the cosmic radiation over the time stretches involved.

    I’ve seen estimates that the galaxy could be explored in 100-million years or so. Even so, I’m not sure it’s a given we would have been found. (Or that any civilization can last 100 million years.) Our radio signals get swamped in galactic noise pretty quickly, and we’re not in a particularly interesting part of the galaxy. We find surprises here on Earth. The galaxy is so much bigger.

    OTOH, compared to the other star systems we’ve seen so far (a narrowly selected group), we do stand out and could seem attractive. So who knows.

    I wonder about nanotechnology, too. It’s hard to make nano machines — leverage and energy issues — and maybe mastering nanotech really means mastering biology, nature’s tiny machines. As Paul pointed out, biology sucks in space. I’m not even sure small things are a good idea — small damage can take out an entire system. I’d almost be inclined to treat it like a heat shield; design big so bits can be whittled away over time. Chips with big transistors.

    Liked by 1 person

    1. Could be on any of that. Interstellar distances may just turn out to be too much of a leap. I tend to doubt it, but until someone manages to deliver a working probe to another star, we won’t know for sure.

      On nanotechnology, biology is our prime example of nanomachinery working. I guess the question is whether the organic type soup is the only substrate where molecules can be productively combined to do work at that scale.

      I’m not too worried about nanoscale devices being more vulnerable. Biology handles that with redundancy, and I suspect anything used in space would have to have a lot more of it. The question is whether it would be so much that the benefits of working at that scale are negated.


      1. “Interstellar distances may just turn out to be too much of a leap.”

        It’s more than just the technical challenges. If we send robots, not people, what’s the incentive for doing it at all?

        Why should a government or private outfit invest billions, if not trillions, on a project with no return value for at least decades, if not hundreds of years. And unknown return that might fail. What’s the purpose of all that?

        We have managed to toss a few spacecraft just outside the Solar system. Voyager 1 is 149 AU out, Voyager 2 is 123 AU. It’s taken them over 40 years to get just that far. As a reference point, the Oort cloud, which is still very much our local Solar neighborhood, is 50,000 AU. (The Voyagers are nicely beyond the Kuiper Belt, though, which just runs from 30–50 AU, so there’s that.)

        “Biology handles that with redundancy, and I suspect anything used in space would have to have a lot more of it.”

        And then some. Space shreds biology. Over time it’s pretty hard on hardware, too. Satellites mysteriously fail sometimes, or part of them do.

        There’s a no-win trade off between going slow (boring and takes forever) and going fast, which slams interstellar particles against you much harder.


        1. In terms of incentive, I think the parameters have to change somewhere. We either need to be able to send something at 20% c or higher so that people will see results in their lifetime, or the cost needs to come way down, or we need to become longer lived as a species, or some combination of all those things.

          There’s no doubt that the engineering challenges are immense. As Greason noted, we have a number of plausible mechanisms to get things up to 2-3% c, it’s after that that things get increasingly speculative. Maybe we never get past 3% c and have to depend on longevity.

          Or maybe none of it’s possible. But that seems excessively pessimistic to me.


          1. Heh, well, my pessimism is from 6+ decades of experience with the human race.

            Formidable, perhaps even unsurmountable, challenges and, again, what’s the incentive, especially if all we send are robots? What do I get for the billions I invest in this?


          2. But we have made progress, at least technological progress, in those 6+ decades.

            Arguably we get the same thing we got for sending a probe to Pluto. Whether future societies will continue to see that as worth it, well, only time will tell.


          3. I don’t disagree. We got back some information that told us things about Pluto and its environment. Which falls under the category of Very Nice. In a way we’re at the stage of just proving we can do it if we have the will. It takes more than technology, it takes the social will.

            Consider an alternate society that took space really seriously and had missions for Titan, Enceladus, Europa, Venus, the asteroids, the gas and ice giants, and the outer rim. Instead, recently, we’ve had Pluto, Saturn, Vesta/Ceres, and some robots on Mars (a bunch of our Mars missions failed). The Chinese, and now India, have had failed Moon missions. We’re mostly just putzing around in low orbit. (We can’t even clean up the growing garbage there.)

            We’re not doing space seriously. Not even close. When you really look at it, I don’t know that we ever have, and I’m not at all sure we ever will. But, as you say, I’m a pessimist on stuff like this; you guys seem to be optimists. Yin and Yang. 🙂


          4. Yeah, I’m not sure we’re going to “do space seriously” until there is some economic interest in it. Scientific interest appears to be enough for robotic exploration, but not for the orders of magnitude more difficult crewed variety. And it’s not clear to me that interstellar exploration ever will, at least not for biological humans.


        2. What’s the incentive? What was the incentive for sending men to the moon? What was the incentive for people signing up to take a suicide trip to Mars? There will always be some people that just want to go. Maybe it will be the Mormons. (That was the Expanse, right?)

          And it’s not like we’re going to fling the first robots at stars. The first ones will probably go to asteroids, or the moon, for mining. And we’ll have them gather materials and make more robots, for more mining. And then someone like Elon Musk will start flinging them at stars, because they can.



          1. We went to the Moon to outdo the Russians after they outdid us with Sputnik. Once we counted coup, we basically abandoned it. I can’t account for Mars, I think that’s just stupidity. The Expanse, of course, is science fiction, which is exactly where some of this day dreaming comes from.

            I totally agree we’ll get out in the Solar system in some way, maybe even in a big way. But again: billions, or trillions, invested in a project with at least decades before any deliverable, if not hundreds of years, and no certainty about what any deliverable might be.

            Information? Other than scientists, who really cares? What’s its value?


  4. Have you read much of Greg Egan’s works? Superb writing, hard sci fi, and in his mind, which I find compelling, the distances are just too huge, so the moment they can any sufficiently advanced society goes digital.

    Liked by 1 person

  5. I agree that the advance of biological life into space will be hard and slow. But the advance of technology into space will be much faster. We’ve already flung a still-functioning probe out of the solar system, as well as put functioning robots on another planet. As soon as we can build robots with human-level intelligence we’ll start flinging those at other planets, and then stars. And eventually those robots will be able to make new robots, and fling those at more stars. All the while we’ll be sitting here figuring out how to make better robots and how to fling them faster, and we’ll be able to send that info at light speed to the robots that are already on their way.

    So John, what does it mean for a society to “go digital”?


    Liked by 1 person

    1. I agree that space belongs to the robots. To the extent biological humans follow, it will be far behind.

      We can definitely fling things at other stars. But if we want them to replicate, we’ll need to figure out a way for them to slow back down.

      On “going digital”, a lot of Egan’s fiction is heavy into mind uploading. If you haven’t seen his stuff before, you might want to check it out. Warning: it’s hardcore stuff. He sometimes has vast stretches of story be about scientific or mathematical investigation. A good one to look at is Diapora. I did post a while back on his vision of an interstellar civilization, which includes links to some of his stories online.


    1. Thanks Linda. In truth I was forced into it. I was having problems which WP support identified as bugs in my old theme, which they informed me was no longer supported. Not sure if I’m going to keep this one though. It’s aesthetically nice, but functionally has some nits that annoy me, and it buries information too much.


  6. Just as a FWIW reference point, I played with some numbers… The Earth’s circumference is about 4 × 10^7 meters. Alpha Centauri, the closest star, is 4.37 LY, which is 4.134 × 10^16 meters. So Alpha Centauri is roughly one-trillion times as far as a trip around the world.

    That makes an interesting ruler for other stars. The closest star is one-trillion times a trip around the Earth. A star 40 LY away, then, would be roughly ten-trillion times a trip around the Earth.

    Thing is, a trillion is pretty much beyond our ability to visualize. We have no intuitions about trillions of anything. Part of my pessimism comes from the recognition that space really is unimaginably large. I don’t think most of us can wrap our heads around how big it is. (Cue the Douglas Adams quote!)


    1. Space is definitely unimaginable in its vastness. But that’s true even for what we have accomplished. If you look at a to-scale model of the distance from the Earth to the Moon, the accomplishment Apollo made in putting men on the Moon becomes evident. And a to-scale model of the solar system emphasizes the vast gulf between the little specks of left over stardust we call planets, yet we’ve sent robots all over the solar system.

      Interstellar distances are admittedly thousands of times vaster. There’s no guarantee we’ll conquer it. But there’s nothing fundamental that should prevent at least robotic exploration.


      1. I don’t think anyone is arguing it can’t be done; I’m certainly not. I am saying the challenges and distances are more formidable than most can realize, the cost and time frames are extreme, while the ROI is questionable.

        The Moon and Pluto make better yardsticks because they result in more reasonable numbers, so thanks! 🙂

        The Moon, at 3.8 × 10^8 meters, it’s 9.5 times that trip around the world. In contrast, the trip to αCent is 108,000,000 times the distance to the moon. (Considering the Moon is only as far away as ten times round the Earth, it’s a shame we’ve ignored it. Just think of the huge radio telescopes we could build on the farside away from Earth’s radiation.)

        Pluto definitely is further, which is why New Horizons was a big deal. At an average (from the Sun) of 5.91 × 10^12 meters, it’s not quite 150,000 times the trip around the world, and αCent is almost, but not quite, 7,000 times further.

        That’s just to the closest star. A star 40 LY away would be 70,000 times further than Pluto.

        At a respectable 10% c, αCent is 40+ years away. If we had good enough communications, we might get data back in 44 years. We certainly wouldn’t get anything physical back for another 40, assuming such a mission could be launched from that end. Again, further stars, longer time frames. Pack accordingly.

        The Pluto mission illustrates something we’ve touched on in other conversations. To get to Pluto in any reasonable time — and given Earth’s orbital velocity to begin with — out at Pluto we were moving fast. We had only a brief time for observations (less than 24 hours, IIRC). A mission going 10% c would pass its target even more rapidly unless we found a way to slow it down.

        The NASA model doesn’t seem to have panned out; too political. We’ll see what the Musk model brings to bear.

        Liked by 1 person

  7. Ahh, excuse me—just one more bong hit. The known universe was sneezed out of the nose of a time-travelling cat. My own cat, anyway, acts like she’s a direct descendant. .As for the unknown universe, well, ,she’s still playing coy. Compliments to, “The Hitch-hiker’s guide…”


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