The Fermi Paradox, Percolation, and Inbreeding • Hacker News Board

Re: The Fermi Paradox, Percolation, and Inbreeding

#31

Post by BrenBarn » Sat, Jul 18, 2026, 8:29 PM UTC

Nevermark wrote: post #22

> Furthermore, light-speed lag and distance mean that child civilizations must be functionally independent of parent cultures. Makes me wonder if a solar system wide civilization, with trillions of beings, wouldn't invest in ships to go to the next system, extract resources, and create a stream of resources ships going back to the original solar system. That might sound uneconomical. Why not just go to the other syst…

> Makes me wonder if a solar system wide civilization, with trillions of beings, wouldn't invest in ships to go to the next system, extract resources, and create a stream of resources ships going back to the original solar system.

This reminds me of those old 4X-type games like "Stars!" where I would often do exactly this. Basically some planets were good for living on and others were good for mining and you'd have a constant caravan of freighters from the latter to the former.

Re: The Fermi Paradox, Percolation, and Inbreeding

#32

Post by yogthos » Sat, Jul 18, 2026, 8:36 PM UTC

lioeters wrote: post #27

yogthos wrote: post #8

The assumption that biological life will be doing galactic colonization seems myopic in the extreme. Let's just consider the progression here. Life on Earth appears around 4.5 billion years ago. Humans start evolving around 2.8 million years ago. Use of language appears around 100,000 years ago. Writing is invented around 5500 years ago. Inventions of language and writing are the landmark moment here. Before language…

Against Mind-Blindness: Recognizing and Communicating with Diverse Intelligences - King's College London Neuropsychiatry Research & Education Group - https://www.youtube.com/watch?v=RHkFmUwW0kM

Sure, intelligence is a gradient, it's not something exclusive to humans. And different biological systems need to solve problems and create models of their environment in order to respond to it intentionally. However, that's tangential to the point I was making, which was that we are able to rapidly accumulate knowledge across generations giving us mastery of our environment that's qualitatively different from any other organism on the planet. And the next logical step here is machine intelligence where human style intellect could be implemented on a non-biological substrate which would open up completely new niches for postbiological life to inhabit.

Re: The Fermi Paradox, Percolation, and Inbreeding

#33

Post by randomImmigrant » Sat, Jul 18, 2026, 9:10 PM UTC

Are we conveniently assuming that only humans will be able to read and tweak their genomes, and do synthetic biology?

An odd assumption if we’re generously granting FTL or even regular space travel to aliens.

Everything from the lack of radio communication to the commonness of biological precursors like nucleic acids and amino acids in space points to multicellularity being the relatively rare thing, at least in our part of the galaxy.

We don’t hear from them or see them because if they’re out there, they’re still microbes eating each other. That one case of the two forming a symbiotic relationship, which leads to more endosymbiosis… that’s where I suspect our real rareness lies.

Re: The Fermi Paradox, Percolation, and Inbreeding

#34

Post by randomImmigrant » Sat, Jul 18, 2026, 9:24 PM UTC

yogthos wrote: post #29

jcranmer wrote: post #24

Earlier quoted context omitted.

> Before language was invented the only way information could be passed down from ancestors to offspring was via mutations in our DNA. Language (in the sense of "use of language appears around 100,000 years ago") is not the only way to communicate information, and many animal species are perfectly capable of communicating information despite not having evolved what is being called "language" in this sense.

The difference is that we are able to accumulate information across generations to grow our collective knowledge. Other animals are not able to do that at scale. So, while you are correct that other animal communicate and even teach each other, it's a qualitatively different situation from human communication.

We really don’t know this for certain at all. We do know crows can communicate information about the face of a person they dislike to their murder, including to new generations. It seems a bit of a stretch to say their cultural transmission is quite that narrow.

In general, pre-writing human oral culture seems to have dynamics much in common with such abilities in other animals. Barring error correction mechanisms, oral knowledge can degrade in transmission, limiting its reach and success.

This isn’t to say human language doesn’t have its distinctive features that are very useful. But the language came from a different brain, and is suited to the particularity of our brains. We should hesitate to place solely on language something that’s also driven by us having more things to say.

Re: The Fermi Paradox, Percolation, and Inbreeding

#35

Post by jacobgold » Sat, Jul 18, 2026, 9:33 PM UTC

sfn42 wrote: post #28

jacobgold wrote: post #17

Earlier quoted context omitted.

That seems unlikely. Just imagine humanity 100, 1000, and 1,000,000 years from now. Humans will have solved every physical problem that is solvable. Humans will have also evolved into new kinds of immortal/superintelligent beings that would be totally unrecognizable to us. It may be the case once a civilization reaches "max level" they universally decide to "reset the game" because there's nothing left to do. Maybe s…

I imagine that 100 years from now(or significantly less than that) the ocean water level will be several meters higher, large parts of the world will be unliveable due to heat waves and wars will be fought over food and water. I doubt our species will last another 1000.

You might try spending some time reading predictions of doom and gloom from the past. It should be very reassuring.

Re: The Fermi Paradox, Percolation, and Inbreeding

#36

Post by qayxc » Sat, Jul 18, 2026, 9:41 PM UTC

sfn42 wrote: post #28

jacobgold wrote: post #17

Earlier quoted context omitted.

That seems unlikely. Just imagine humanity 100, 1000, and 1,000,000 years from now. Humans will have solved every physical problem that is solvable. Humans will have also evolved into new kinds of immortal/superintelligent beings that would be totally unrecognizable to us. It may be the case once a civilization reaches "max level" they universally decide to "reset the game" because there's nothing left to do. Maybe s…

I imagine that 100 years from now(or significantly less than that) the ocean water level will be several meters higher, large parts of the world will be unliveable due to heat waves and wars will be fought over food and water. I doubt our species will last another 1000.

I'm very confident our species will last longer than the next 1000 years. Our current civilisation, though, now that's a completely different story.

Re: The Fermi Paradox, Percolation, and Inbreeding

#37

Post by lukebuehler » Sat, Jul 18, 2026, 9:51 PM UTC

yogthos wrote: post #8

The assumption that biological life will be doing galactic colonization seems myopic in the extreme. Let's just consider the progression here. Life on Earth appears around 4.5 billion years ago. Humans start evolving around 2.8 million years ago. Use of language appears around 100,000 years ago. Writing is invented around 5500 years ago. Inventions of language and writing are the landmark moment here. Before language…

I’m thinking along my similar lines. Expansion, if it happens, will likely not be on a recognizably human substrate, but rather something else. But currently it’s more of an intuition than a rigorous argument for me. How do would you formulate a more solid argument around this idea?

Re: The Fermi Paradox, Percolation, and Inbreeding

#38

Post by NitpickLawyer » Sat, Jul 18, 2026, 9:55 PM UTC

yogthos wrote: post #8

The assumption that biological life will be doing galactic colonization seems myopic in the extreme. Let's just consider the progression here. Life on Earth appears around 4.5 billion years ago. Humans start evolving around 2.8 million years ago. Use of language appears around 100,000 years ago. Writing is invented around 5500 years ago. Inventions of language and writing are the landmark moment here. Before language…

> For all we know the Universe may be teeming with intelligent life and we just don’t recognize it as such.

This is my preferred answer to the Fermi question as well. Unless two civilisations are in a precise (and likely small) window where they both can and want to communicate, it's likely the less advanced one wouldn't even recognise the other one. Especially if the other one doesn't "want" to be recognised.

Re: The Fermi Paradox, Percolation, and Inbreeding

#39

Post by qayxc » Sat, Jul 18, 2026, 9:56 PM UTC

pianopatrick wrote: post #7

jmyeet wrote: post #4

This is a kinda silly argument. Interstellar colonies would have the opposite problem: they'd cease to be the same species due to genetic drift. If you look at the (im)practicalities of interstellar travel, it's going to take centuries. That means a generational ship of some kind. That means having a sufficient population to get there, which really means tens of thousands of people. Plus, the kind of ship that would…

I don't know if a generational ship is absolutely required. There's this assumption that interstellar ships would be full of human astronauts who are alive and awake. But that might not be strictly required. You might be able to have everybody go there frozen. Or have a robot ship that gives birth to the colonists from an artificial womb on arrival.

> You might be able to have everybody go there frozen.

Common trope in sci-fi, pretty much impossible in practise. Humans aren't capable of surviving being frozen, we lack the genetic machinery for that. Could you breed/engineer hybernation-capable humans? Sure. Otherwise this approach would require to literally being able to kill and then resurrect people at will.

> Or have a robot ship that gives birth to the colonists from an artificial womb on arrival.

I like this idea. It kills two birds with one stone: for one, fertilized eggs and fetuses can be stored safely for a long time.

Secondly - and I think this is something that's underdiscussed - genetic modification will be necessary anyway. The target environment won't be a carbon copy of Earth. Different atmosphere, different gravity, different starlight, different pathogens, etc. If you insist on colonising planets and start terraforming via automated means ahead of time, the resulting ecosphere will still differ from Earth and adjustments will be necessary. A ship carrying unborn settlers would be informed of the specifics of the target world and the ship's biolabs could make genetic alterations accordingly.

Re: The Fermi Paradox, Percolation, and Inbreeding

#40

Post by gcanyon » Sat, Jul 18, 2026, 9:59 PM UTC

This argument seems, frankly, absurd to me on multiple fronts.

First, it assumes that lack of genetic diversity in humans would be a serious handicap, when we're considering humans that are capable of making interstellar journeys. Assuming that genetics are going to be an issue compared to traveling/surviving 7 or more light year-journeys is a leap.

Second, it assumes that if this were a problem, humans would/could think of no way to address it. Two solutions come immediately to mind: 1. Choose the people making the journey more carefully to ensure diversity 2. Send frozen embryos chosen for diversity along.

Third, it ignores the time scale over which something like this would be likely to happen. Of course, you can't guarantee that beneficial diversity will re-occur, even over centuries, but a little effort on the front end combined with the time it would take to continue on to the next hop seems hopeful.

Fourth, it ignores the possibility of repeat journeys. If we're really going to constrain the available destinations in the way presented, it's silly to propose that there will be just one colonizing event.

But really, the first solution is all you need. The idea that we'll be able to survive multiple generations in space but not handle genetics issues is, just, a real stretch.