The Great Filter is the idea that, in the development of life from the earliest stages of abiogenesis to reaching the highest levels of development on the Kardashev scale, there is a barrier to development that makes detectable extraterrestrial life exceedingly rare. The Great Filter is one possible resolution of the Fermi paradox.
https://en.wikipedia.org/wiki/Great_Filter
The Fermi paradox is the discrepancy between the lack of conclusive evidence of advanced extraterrestrial life and the apparently high likelihood of its existence. As a 2015 article put it, “If life is so easy, someone from somewhere must have come calling by now.”
https://en.wikipedia.org/wiki/Fermi_paradox
Personally I think it’s photosynthesis. Life itself developed and spread but photosynthesis started an inevitable chain of ever-greater and more-efficient life. I think a random chain of mutations that turns carbon-based proto-life into something that can harvest light energy is wildly unlikely, even after the wildly unlikely event of life beginning in the first place.
I have no data to back that up, just a guess.
Boy, Lemmy sucks donkey dick. For every one legitimate answer there are two or three edgelord answers like “capitalism” and “the internet”.
Here’s an answer that hasn’t come up yet: cooperation among mono cellular organisms. I don’t mean the development of polyp analogues or colonies of single celled organisms; I mean getting down to mitochondria. Brace for wild oversimplification.
Before mitochondria, life had a hard time creating enough energy to do much more than barely stay alive. The current line of thinking is that one organism ate another and didn’t digest it. The two organisms worked symbiotically, one handled energy production and the other handled getting food and staying alive.
Just about every living thing utilizes mitochondria and if the current idea that mitochondria were actually symbiotic organisms is true, that means that what was likely a chance “sparing” of prey is the underpinning of all complex life.
The odds of that happening are ridiculously low. There could be simple life in tons of places even within our own star system, but if the mitochondria-like symbiotic capture never happens for those extraterrestrial organisms, then complex life is probably unlikely to develop.
Edgelord teenagers are a plague on lemmy
A - fucking - men
Still not as bad as reddit though
Good answer. This seemed relevant enough to share, it’s certainly interesting. https://newatlas.com/biology/life-merger-evolution-symbiosis-organelle/
your paragraphs complaining about it are a lot more annoying than the people who might not be being totally serious on the internet for a minute.
If by “paragraphs” you mean two sentences, sure.
If you’d bothered to read past those two sentences you’d see that I was making an offhand comment before answering the question.
nah if you open up just insulting all the people around you, I don’t owe you reading the rest of your post.
Case in point for Lemmy being a shit hole.
Maybe cooperation is hard wired just like competition. It might be less likely but hardly impossible.
I’d hardly describe it that way. It took untold trillions of predator/prey interactions over the hundreds of millions of years that single celled life existed for it to happen. That’s more or less brute forcing the problem and it took geologic timescales to happen.
If you ask me to point at a hurdle stopping civilizations from developing that looks awfully reasonable.
Ultimately we don’t know much about that era of time, but I suspect it was less like fumbling around for millions of years looking for a light switch, and more like the gradual warming of the planet with warmer and cooler seasons/years.
Iirc at least one of the other things related to development of eukaryotes was that atmospheric oxygen had to first be generated by early cyanobacteria.
So maybe that proverbial light switch was being flipped millions of times through random encounters but only became more viable after the voltage (atmospheric oxygen levels) became high enough. Maybe that’s the reason it took hundreds of millions of years, because transforming by bacteria just takes that long.
We just don’t know unfortunately. However, we DO know about species getting wiped out by asteroids or human cultures getting wiped out by disease or conflict with superior cultures. Any of these filters seems more of a hurdle to me than the development of eukaryotes.
Everyone is talking about society or physiology stuff. That is just things that might get humans.
Stars going super-nova is the real great filter. Our sun is 4.6 billion years old. Life started 4 billion years ago. In 4 billion years, the sun goes supernova. We are halfway to the end of the earth.
Smaller stars last longer, but have smaller ranges that life can exist in - and planets tend to move in or out in their orbits. Bigger stars have giant habitable zones - but some large stars born when humans took their first steps are in their last decades of life. You couldn’t get from the pyramids to NASA in that time, never mind the 4 billion years it took to get to humans.
I think it’s supposed to actually less than that, the sun’s luminescence will increase over the next 1 billion years to the point that it will boil off the earth’s oceans. No life will be able to exist past that, and earth will just be a barren rock in orbit for the next 3 billion years.
Well I’m doing my part to make sure the oceans are full of Arctic ice for the great boil off
When they do boil off they need to make sure to have a hell of a lot of cocktail sauce and melted butter on hand.
While that is true I would counter point that humans have a bit of a handicap as earth got hit by a big astroid that killed just about everything on it making terran life have to start all over again but at the other hand I saw someone else on here mentioned that oil has given us a head start at space ferrang advancement and oil is made from dead life so granted I haven’t done much reacerch on how oil forms naturally but I do wonder if we would have oil if earth never got blown up but on top of all that there are theorys that mars used to have life so if astroids haven’t interfered with our solar system intelligent life may have formed faster and maybe twice also there used to be multiple species of humans in the past so maybe 4 or five times in the same solar system
That is an interesting idea that is not typically considered in the drake equation as far as I know. That could significantly reduce the chance of finding intelligent life elsewhere.
I think it is in the drake equation effectively, it factors into the length of time that the civilization might send and receive detectable signals - It doesn’t say why the Civilisation might collapse, but the planet becoming uninhabitable is surely one reason. On wikipedia for Drake Equation the Carl Sagan specification of L is in terms of the “fraction of planetary lifetime”.
I think a missing factor might be how directional transmission and receiving is, if we can’t broadcast to and listen to the whole sky equally then we might have a 1/r-cubed type issue with the chances of both listening and transmitting with enough strength/energy at the same time.
It may very well be republicans
seriously though, I think life on other planets probably just usually evolves underground, so even if they develop some sort of intelligence they’re not looking up at the sky so they have no motivation to explore beyond their atmosphere no matter how advanced they get.
there was a planet in The hitchhiker’s Guide to the Galaxy universe that had thick cloud cover so that people never even conceived of an existence beyond their planet. when a spaceship crashed there, it never even occurred to them that it might have come from the sky
Even if you had a super intelligent species that can make Dyson spheres and travel at the speed of light the observable universe is beyond vast. I don’t know much about cosmology or our ability to detect light but given humans have only been looking into the sky for a couple centuries, not being able to see a thimble in the ocean seems like a non issue. I think if you scale the observable universe down to the size of earth the speed of light becomes 0.05 mph.
evidence of human existence has only gotten what, 150 lightyears out into space?
Eh. The amount of oxygen in out atmosphere is pretty much impossible by non-living processes alone iirc. Anyone who can do astro-spectroscopy can probably tell there’s life here, from thousands of light years away.
and if life is as abundant as we think, how are they going to tell the difference between intelligent and non-intelligent life
Life is so rare, finding ANY life is worth investigation
that has nothing to do with why I asked that question lol. if you have to investigate every single one that shows signs of life, that would mean investigating a lot of worlds before you find any with intelligence.
By the color of their hats /jk
Energy needed to leave your planetary system vs energy available on your planet of origin.
We have not yet overcome it and I am not sure that we will achieve it.
Well, we’ve already sent a couple of probes out of the solar system, but they’re not really going fast enough to have any meaningful interstellar impact.
Yes, but I mean leaving the planetary system not only with isolated elements, but with parts of our civilization.
I think we’re the first. Or rather in the first wave of intelligent life. It could take a thousand years just for a message to reach us. On the theory that life has evolved to this point as fast as possible over the life of our Galaxy, there’s no filter. There just hasn’t been enough time for contact to occur.
Time itself is the filter. I don’t think we are the first, but I don’t think we will every find any other intelligent life. The universe is too big and our lives are far too short to make any sort of attempt to travel or communicate across those distances ourselves. I’m also not entirely confident our idea of what a society is will last in any meaningful way over the timespans required. Our longest lasting dynasties rarely make it more than a couple hundred years. Space is just too big for us to work with using our current understanding of physics.
I don’t think there is a great filter. I think there’s an easy solution to the fermi paradox that doesn’t require great filters, we’re just the first intelligence in this galaxy.
Here’s my reasoning: intelligent species that manage to develop space travel probably do tend to expand out into their galaxy. When they achieve this level of technology they can settle most of all of their galaxy in a matter of 10,000 years or so. That time period is very brief on an evolutionary scale. It’s estimated that life began on earth 3.7 billion years ago. That means it took about 3.7 billion years for earth to produce intelligent life, and then from that point it would take a mere 10,000 years to reach modern day, and 10,000 more years to settle the whole galaxy. That expansion happens so quickly compared to how long it took the planet to develop intelligent life, that the chance of two civilizations rising at the same time becomes very small.
It all boils down to this: there are no intelligent aliens out there in our galaxy, because we are the first intelligent species in our galaxy. We know we’re the first because if we were second, then aliens would already have settled this star system.
Probably there are lots of alien civilizations out there in the universe, but they’re in different galaxies.
and the ones finding apes on a planet just short ahead or into the beginning of those 10000 years might think “well lets teach them how to stack stones and let them call us gods for just showing some of our million years old and cheap replicated tech gadgets pewpew, how amusing! but now lets go on, this planet has water but way too much oxygen and also there is axial precession that would change weather over only few hundrets of thousands of years if not less, not the planet of choice for eternals like us, duh!”
Or we just don’t know, because every possible indicator is gone after a few hundred million years or our star system was still a proto disk when they were around.
That assumes that interstellar travel is possible. Physically, economically, socially, there’s a lot of boxes to check for near-light extrasolar expansion (let alone FTL, which probably is impossible)
I think the easy solution to the Fermi Paradox is that we’re stuck in our fish bowl and so is everyone else.
That’s true, it does assume interstellar travel is physically possible, but at this point there are forms of interstellar travel that we know are possible.
Solar sails for instance, we know those work, we’ve tried it. Now if you wanted to travel to another star system with a solar sail, it’s just a matter of scaling that proven technology way up. We’re not ready to do that today, and we won’t be ready in the next 20 years, but to think that we wouldn’t be ready in 500 years, I find that idea far fetched.
But a much better technology would be fusion propulsion. With fusion drives you could get your cruising speed up to a meaningful fraction of the speed of light (perhaps 5-10%). At that rate you can make it to the closest stars in less than 100 years. And that technology is not at all far fetched. We truly are approaching working fusion power plants, it’s extremely likely that we can eventually develop fusion propulsion, or at the very least, fusion powered electrical propulsion (ion drive).
As for if it will ever be economically possible, I’m not at all worried about that. The fact is, there are a lot of resources and opportunities right here in our solar system, just waiting for people to utilize them. So people definitely will start mining and manufacturing in space eventually. And as we start to operate more in space, we will naturally continue to iterate and improve our methods of getting around. In short, over time it’s going to get cheaper and cheaper to make space ships and we’re going to get better and better at doing it. The economic factors are likely to fall into place eventually.
And finally, will interstellar travel ever be possible socially? Hey, your guess is as good as mine. I don’t think we have any way to answer that…
But why are we the first. That’s the question. Given the age of the universe, statistically it should have already happened by now. Unless something was stopping it.
Statistically I shouldn’t fail a 99% roll 7 times during a single mission in XCOM and yet here we are.
“weird coincidence” is one potential solution to the Fermi paradox.
It could simply be that the rise of life is wildly more rare than we think.
Yeah, it totally could be.
That’s definitely the right question! And honestly we don’t know, but it’s evident that we are first.
Given the age of the universe, statistically it should have already happened by now.
I’m not sure that’s true… I’m pretty sure that our sun is old for a main sequence yellow star in our galaxy. When you compare how long it takes for a star to get to the point ours is now, compared to the age of our galaxy, I believe it suggests that sol is part of a first wave of stars of its type. So if life really requires a star like this one to start up, then intelligent life starting just now could be right on time.
Now why is our start perfect for life? Again, we don’t know, but evidently it is. Sadly we only have this one data point, this is the only star where we know there’s life. So assuming that something about our type of star is perfect is about as sensible as assuming that life could start around any star. Is it that other kinds of stars produce too much radiation in the Goldilocks zone? Or is it that other kinds of stars are too variable in the amount of heat they produce? Or that other kinds of stars don’t tend to have rocky planets? We don’t know, but something about main sequence yellow stars could be special, and we have one of the first of those stars in this galaxy.
So declaring “we’re the first” requires some assumptions, but they aren’t crazy assumptions, and a lack of evidence of other older civilizations makes those assumptions stronger.
And to your point, the universe is much older than this our star, so I suspect intelligent life has developed many times before us, at least in older galaxies. But sadly I don’t expect us to ever meet life from another galaxy. While I think stars within a galaxy are close enough for travel between them, galaxies are very, very far apart. I don’t think life has much chance of traveling to other galaxies, at least not without some method of ftl travel (which I am also not optimistic about).
It might have something to do with the available elements.
We live in a population I star system, full of crap spewed out from long dead stars. Perhaps it is exactly this crap (like copper, iron, nickle, manganese, and possibly the bulk of carbon and nitrogen) that allow life to develop with enough agility to survive mass extiction events with any kind of complexity.
Or perhaps it’s exactly those mass extiction events that have allowed enough breathing room for new paradigms to take hold. Maybe our 5-7 mass extictions that didn’t end life entirely are exactly what is needed to prevent stagnation. We just happen to be on the edge of dead and too slow.
The Milky Way is 100,000 light years across. It’s physically impossible to settle that in 10,000 years
In my sci Fi that I’ve been working on has this theory being true but I also play with asking what is the point of colonization. In my story humans have colonized mars to study the fossils and what life used to be like on Mars. However the people there after a few generations separate from earth. Earth doesn’t do anything about it because not only can mars use telescopes to see our ipbm years before it arrives and have that time to shoot our ipbm before it arrives but invasion will destroy the fossils we care about. And that’s all assuming history won’t just repeat itself. Eventually the mars colony expands until it breaks into different nations all fighting echother to become the first martin superpower. So everything that earth cares about gets destroyed by war anyway and earth is pointless to mars without life and water. Eventually the sun becomes so old that everyone feels the need to move their populations to another solar system. And only then de humans discover alien life. Only to discover that it’s currently 900 billion years beyond 2024 and aliens are just now figuring out radio waves and rockets and are more concerned about developing eugenics than discovering humans.
I don’t think life is rare, nor photosynthesis, but complex life might be. A planet needs to be really thriving with life for it to be worth it to go down the path to something like animals
But I think the bigger filter is much stranger.
Humans are a hive-like species. We’re not just social - we’re insanely interdependent, we don’t function on our own and yet we’ve ended up in this place where we (often) try to individually succeed, even at the cost to our community
We’re greedy enough to want the stars, yet interdependent enough we could only swarm over them in endless numbers
There’s many problems with the fermi “paradox”, but personally I think one of the largest is assuming all species would spread like a cancer blotting out the stars
A more individualistic and long lived species might instead be careful explorers, taking what they need and leaving little sign of their passage. A more communal species might be careful and control themselves to not destroy pointlessly. They might also feel no desire to contact other species
We’re just the right mix to want everything a star could give, and to want to find others at great energy cost
God help the universe if we ever discover FTL travel and escape the prison of lightspeed.
I have a new religion!
Prometheus didn’t gift us fire and cognition. Lies. We are Prometheus’s curse on the universe. Nothing more than a plague on the gods creation, concocted for some slight we can never understand. The sum of us, brought into being, then tossed into the void and forgotten. To spread like an oil stain across creation.
“And behold, I Myself am bringing floodwaters on the earth, to destroy from under heaven all flesh in which is the breath of life; everything that is on the earth shall die.” - Genesis 6:7
“If you had not committed great sins, God would not have sent a punishment like me upon you.” - Genghis Khan
I don’t think there is a single universal Great filter, and living and then potentially sentient beings with various traits will face various obstacles.
First, life needs suitable materials for polymers and a lot of energy. Most places don’t have both.
Next, basic blocks of life that would be self-replicating and adaptive should be randomly generated, which is extremely unlikely and literally took over a billion years on Earth, a planet with generally great conditions for such process.
Then, those blocks should be able to get together to form complex structures - ideally, many separate ones, so that one event wouldn’t destroy the entire effort. Earth had it easy, with billions of super simple life forms.
Next, assuming life survived up to this point in a potentially unfriendly and ever-changing environment, bombarded by UV light and exposed to myriad of sources of damage, it should not destroy itself or environment too badly to never recover. Earth had periods when life generated too much carbon dioxide or too much oxygen (yes, that too was a thing), and those were critical points at which our story could very much end.
Then, life has to evolutionize and get into complex forms, either by forming multicellular organisms or by making a cell a powerhouse of everything.
Then, life has to get sentient, and some kind of response system should be available and get highly complex.
Then, most of the sentient creatures just won’t be tribal, and civilization requires society and a common effort.
Then, many more won’t be expansionist, and will die out in some small region.
Many also won’t be competitive, which would slow down evolution.
For those species who are competitive, they shouldn’t destroy each other while they’re at it, and this is currently one of the risks of our own.
And after all that, they should develop space travel and either get as developed and decisive and resource-rich as to send a generational ship to some random planet named Earth populated by genocidal monkeys, or to somehow hyperdrive here. They can very much decide it’s not worth it, and they may be so far away we couldn’t see signs of their civilization.
Pushing Ice by Alastair Reynolds is one of my favorite scifi books and it deals with this question in an interesting way. It proposes that Time is the great filter. Life exists in this galaxy, but intelligent life is so fleeting when considering galactic distances that the probability of one sentient lifeform finding another during their “peaks” is vanishingly small. Extinction, societal collapse, evolution to a higher form, whatever you want to imagine, it all gets in the way of the fantasy of meeting a thinking being from another planet.
For us it’s conservatism and its synonyms.
Read like any history book.
Or just about any book, really.
I think that it’s you who should read more.
Here:
We propose that the global environmental crises of the Anthropocene are the outcome of a ratcheting process in long-term human evolution which has favoured groups of increased size and greater environmental exploitation. To explore this hypothesis, we review the changes in the human ecological niche. Evidence indicates the growth of the human niche has been facilitated by group-level cultural traits for environmental control. Following this logic, sustaining the biosphere under intense human use will probably require global cultural traits, including legal and technical systems. We investigate the conditions for the evolution of global cultural traits. We estimate that our species does not exhibit adequate population structure to evolve these traits. Our analysis suggests that characteristic patterns of human group-level cultural evolution created the Anthropocene and will work against global collective solutions to the environmental challenges it poses. We illustrate the implications of this theory with alternative evolutionary paths for humanity. We conclude that our species must alter longstanding patterns of cultural evolution to avoid environmental disaster and escalating between-group competition. We propose an applied research and policy programme with the goal of avoiding these outcomes.
Figure 2. Dimensions of environmental management create an attractor landscape for long-term human evolution. Environmental sustainability challenges (curved frontiers) require a minimum level of cooperation in a society of a certain minimum spatial size. Alternative potential paths move humanity toward different long-term evolutionary outcomes. In path B, competition between societies over common environmental resources creates cultural selection between groups for increasingly direct competition and conflict. Path A, growing cooperation between societies facilitates the emergence of global cultural traits to preserve shared environmental benefits.
A Great Filter is way, way bigger than that. Something that prevents a civilization from being able to expand into space. This includes things like “you can’t make fire on this planet and therefore are never able to learn to work metal” and “supernovas sterilize regions of space before species can leave them”.
Even the worst ecological disaster - one that kills billions - will not prevent humanity from eventually recovering, rebuilding, and expanding.
Under no circumstances (even Cold War mutually assured destruction) can human politics be a Great Filter. Thinking that it can be is small-minded and petty.
I see, so you don’t understand what’s happening on the planet.
Don’t worry, you’re not alone, you represent the majority.
I’m sure simply continuing to live will show me more about possible great filters than most teachers could unfortunately.
sentience. I think it usually immediately leads to suicide
