The timing of evolutionary transitions suggests intelligent life is rare | Hacker News Reader

The timing of evolutionary transitions suggests intelligent life is rare

liebertpub.com

148 pointsbeefman147 comments

Don't a bunch of squids, birds, other primates, etc. show plenty of intelligence? Yet none show any ambition to develop high tech that anyone could spot from space, chimps don't even feel the need to communicate all that much even though they're totally capable of using sign language when properly incentivized, they just don't seem to have the urge to express themselves like we do.

Might that not imply that intelligence is pretty frequent, but that what we're looking for isn't intelligence per se, but a bunch of other very specific qualities and factors that channel intelligence to express itself in high tech spacefaring ways? Seeing how much had to fall into place just so in the last 100 000 years so we could put someone on the moon, I guess that seems plausible?

That’s mostly a question of how one chooses to define “intelligence.” For the purposes of this type of discussion it’s usually equivalent to “whatever humans have that other animals don’t.” We’re looking for something that would be relatable to us, probably the minimum requirement would be the ability to communicate with them at the same level of robustness that we can with each other (edit: or a recognizable demonstration of mastery over the physical world to a level that meets or exceeds our own).

It’s true that other terrestrial life forms possess some capabilities that we could call intelligence, but then we would just need to use another word that defines the special human je ne sais quoi.

Probably the most relevant difference is humans forming prestige hierarchies alongside dominance hierarchies with larger brains able to store more of the resulting cultural accumulation being partially downstream of that. Knowledge transmission is always imperfect but if people try to learn from the guy reputed to be the best flint napper you can support a lot more technology than if everybody just learns from their parents.

Learning from non-kin isn't unusual in the animal kingdom. Monkeys seeing other monkeys drop a mix of sand and grain in water to separate them and then copying that is a classic example. But deliberate teaching of non-kin and the way we use language to help with that teaching is pretty unique. An octopus might have smarts comparable to a feral human, but not to an acculturated human.

Yet none show any ambition to develop high tech that anyone could spot from space

Above the sea level, anyone who had it is either a part of “our” genome or extinct. Below it is a completely separate biome which may not yet had an event starting this type of evolution. It’s unclear if in a million years (in the absence of humans) squids would stay the same or evolve into walking and then moon-landing.

I think that only one species can do that, because the most energetic natural environment (free oxygen in our case), which is required for it, is usually only one per planet, and you have to fight over it, with hands, wood, metals, fire, ATGMs.

> Above the sea level, anyone who had it is either a part of “our” genome or extinct.

That's too vague to argue with but I'll do it anyway: No, elephants and crows as just two examples.

I mean one can spot an elephant from space, but a crow? :) I was talking in a high-tech context, of course there are pretty intelligent species besides us, but they don’t build lit up megastructures.

The comment you were responding to already has that as an assumption and is saying that they don't do those things not because they can't but because they don't have ambition to do them, so the fact that they don't isn't a measure of intelligence.

Ants and termites build megastructures..

You can see beaver dams from space, or atmospheric oxygen. Only sending radio signals is uniquely human.

In terms of space, single called organisms have traveled further from earth than people have. So calling us spacefaring is kind of misleading in the context of alien life. I doubt we’re detectable outside of a 100 light year sphere from earth and none of those stars look like they contain any habitable planets. The only way to suggest alien intelligent life is meaningfully different than beavers in this context is to raise the bar far enough we don’t qualify.

Surely no single celled organism built a spaceship or other launch system to go into space because it wanted to do so?

The ability of humans to willingly create the technology to do it is what counts, in this case.

Neither had humans until very recently.

>I doubt we’re detectable outside of a 100 light year sphere from earth and none of those stars look like they contain any habitable planets.

Do you have a source for that?

You can build better receivers but eventually only so many photons are being sent. Prior to 1921 people were sending out very little radio waves and the signals where vary weak. The you might move things back to say 1920 with the very first radio station but it really wasn’t putting out much power. Things ramped up fairly quickly though, at least assuming something built a truly massive detector at 100+light years.

For comparison look at what we need to do to detect messages from the voyager 1 at 1/400th a light year, realize that’s sent from a directional antenna and we know exactly where to look for it. A signal that’s ~1/1,600,000,000th as strong would take some serious hardware even with more advanced technology because you can only collect 100% of the photons in a radio transmission quickly you need a physically larger device.

GP's reasoning is probably: the only plausible way to detect human civilization (and not just our planet, which is already hard enough from a different star) is by it's radio signature, and the oldest radio emissions is from 100 years ago, give or take. Anyone standing outside of a sphere whose center is earth and radius is 100 light year hadn't been reached by our oldest detectable-from-space civilization artifacts yet.

It strikes me as a pretty intuitive arguemnt to make and true by default, to show it wrong you have to find or somehow plausibly argue for the existence of some physical medium or process that human civilization (or even earth life in general) emit or modulate in unique, detectable-from-space ways other than electromagnetic waves and that we have been doing this since before radio.

Something could detect oxygen at longer distances, but that isn’t a sign of intelligent life.

An unaccountably high level of carbon in the atmosphere could be such an indicator.

I think it might be considered evidence, but CO2 levels vary quite a bit over time. Picture what would happen if we measured atmospheric bass on a planet over a few hundred years and saw that kind of swing in CO2.

Decidable radio signals on the other hand are far less ambiguous. I just can’t think of much that would be both detectable and a smoking gun.

*gas not bass dam auto corrupt.

Lots of discussion on that [1].

In general, the signal from our most powerful commercial radio transmitters will go below the background noise floor well before 100 light years.

However, a very low bandwidth pumped through something on the scale of the Arecibo dish at the transmitting end, and a helium-cooled receiver, could bridge many more light years. But then we're no longer talking about a sphere of a signal or even a big cone, but in astronomical terms an extremely tight-focused point-to-point laser that is more apt to just intersect cosmic dust and gases than an alien civilization.

[1] https://www.quora.com/How-far-do-radio-signals-travel-into-s...

His source is probably the amount of time we've been dabbling in radio comms.

However if the aliens had a big telescope surely that radius would expand?

> However if the aliens had a big telescope surely that radius would expand?

I think a more interesting question is how far away could we detect a civilisation equivalent to our own, using our current technology. Otherwise you can assume aliens (or our future selves) with arbitrarily sensitive detection equipment limited only by whether or not the detectors are inside the speed-of-light radius of the emitting civilisation.

IIRC our most powerful transmissions have been from NORAD radars looking for missiles coming over the north pole. In some ways we are now emitting less detectable signals, e.g. with lower power 5G cells and fibre broadband replacing good old radio.

There is clear line between human and animal intelligence, the language. It's this ability to exchange information about arbitrarily complex ideas, or, one might say, to exchange and store thoughts in a serialized form, that sets our intelligence apart and opens the possibilities for a civilization as advanced as ours. No other species on this planet has I/O capabilities this advanced.

Indeed, I think it's clear a lot of animals can do a lot of things that they just don't want to do and the reason they don't want to is because that just wasn't beneficial for them in their environment. Maybe cultures could be created and spread amongst them that might bring out that ambition though.

> chimps don't even feel the need to communicate all that much

Because that wasn't providing any evolutionary benefit. Take a group of chimps, and make offspring of those who communicate more often to have a higher chance of survival, and voila -- they will develop an urge to communicate!

Only possible issue-- it'll probably take a few million years

Sounds like a neat experiment.

Perhaps it should be done.

Of course, it’s so much easier to simply imagine such things. All that ‘scientific method’ stuff is just a nuisance when it comes to evolution.

Intelligence without ambition puts a hard bound on future intelligence.

Humans also didn't show any ambition, besides keeping themselves and their little band alive, for hundreds of thousands of years. We know they had the mental capacity because hunting, foraging, cooking and tool-making needs knowledge and planning, but they were fine as they were.

Somehow humans started cooperating in large groups, planting the seeds of civilization, outcompeting (or possibly exterminating) our less social brethren. We can't know if the first human capable of leading large groups was a genius or a psychopath, but without people like him/her humanity probably wouldn't be very ambitious.

The most fun idea in this article is a tacit proposal to look really hard for signs of advanced technologies in and around red dwarfs because they have had the potential to support an oxygen-rich biosphere for at least 10x longer that earth: roughly 8 billion years versus 800 million years.

All red dwarfs are flare stars, with solar winds 10 times stronger, they heat less so planets must be closer which makes it even worse.

Yeah. One danger for life is the star cooking it. But the other is that the solar wind will tend to strip away a planets hydrogen if life doesn't develop photosynthesis to give the planet an ozone layer fast enough. It took life on Earth most of a billion years[1] fooling around with chemosynthesis before photosynthesis took off. It's a hard step and life around a red dwarf would be on a much more stringent timeframe than life on our planet was.

[1]http://hopefullyintersting.blogspot.com/2018/03/the-drake-eq...

This does feel like there's some selection bias here. The assumption is that intelligence hasn't developed before humans. If a planet wide civilization would have sprung up say with the dinosaurs, would we have gotten a shot? It seems somewhat plausible that such a civilization would either have survived ruling any subsequent rise out or have blown up the planet in a way that none would arise either.

I’m not sure this is what you meant, but onto a tangent:

I feel like us humans have deeply romanticized dinosaurs as these incredibly dangerous, vicious, aggressive creatures. And I’m just not sure there’s any evidence to support that.

If we unearthed bear skeletons a million years from now, we’d think that humans couldn’t cohabitate with bears. Such size. Those teeth. The claws! But bears generally steer clear of humans. Perhaps dinosaurs would too.

Of course I barely know what I’m talking about. But it has me quite curious.

"we can't prove they weren't huge fatbirds!" https://imgur.com/gallery/rmad4

I hate this recent trend of shitting on paleoartists as if they have no idea what they're doing. Many species of dinosaurs had feathers. Thus far there's no evidence T. Rex did. If it did, they wouldn't be a huge coat like that due to thermal consequences.

At the very least we had no particular reason to assume dinos had the canonical stone colored skin with no markings.

I find that equally terrifying. I’ve seen firsthand what happens to a frog when it hops into a coop of 7 chickens

Humans and their ancestors were strong enough that anything that evolved alongside them adapted to avoid humans or risk extinction. I'm not sure if human evolution from a simple mammal could survive alongside dinosaurs long enough to reach the point where we could effectively defend ourselves. I imagine we'd mostly be stuck either being small enough to evade them or stuck hiding in trees off the ground.

It's a weird assumption that something like a Trex would even bother with a scrawny human with barely any meat on it when there's much more meat to be had from other dinos.

Chickens eat bugs. It's not so far off.

It seems a bit optimistic to say that humans are willing to cohabitate with bears. If there are bears in a human population centre they will be exterminated.

Ignoring a different climate humans probably could have existed at the same time as dinosaurs. We would also have all-but wiped out anything larger than us by now though.

A lot of Canada cohabitates with bears.

Naturally our existence stresses and displaces them. But they’re there and you see them in the news quite regularly. Except for places like cottage country where their presence in your garbage isn’t news worthy.

black bears all over the NE USA and cohabitate. You just gotta chase em out of your garbage sometimes.

This seems like an appropriate time to recommend the book West of Eden [https://en.wikipedia.org/wiki/West_of_Eden].

It posits an earth where humans and dinosaurs co-exist, but the dinosaurs, having been around longer, are the dominant species.

A planet wide civ would be pretty difficult. I don’t think the earth would have enough Coal or oil to allow for easy energy access.

If only there were abundant sources of energy around like maybe nuclear fusion from a giant orange ball in the sky? Or perhaps hydro electric from the plethora of oceans? It wouldn't be easy, but it would be possible to create enormous amounts of energy from the normal daily cycle of the waves if it became necessary.

There are plenty of ways to create energy given the abundance of resources on this planet, even before homo sapiens.

> It wouldn't be easy,

It would be multiple orders of magnitude more difficult, and for all practical purposes impossible. You’re drastically underestimating civilization’s historic reliance on coal.

Also, fwiw you don’t get hydro electric power from the ocean. Hydro power is from water falling. Tidal power is a thing but it’s not easily achieved.

Civilisation started heavily relying on coal a few hundred years ago. The Earth was well-dominated by humans by then. It very probably would have taken a lot longer to get to where we are now, but I don't think there was any danger of seventeenth century civilisation falling to dust because there was no coal to be found.

All coal was produced during a 50 million year window when the earth lacked a decomposition process that could breakdown lignite. Once that evolved the formation of coal around the planet halted abruptly.

There’s a possibility humans might consume that resource dooming all subsequent civilizations to what you point out.

It's possible that absent coal, oil, or natural gas we would have leap frogged directly into solar power first with directed mirrors powering a liquid turbine, wind, and eventually conventional solar panels made from silicone.

There's really no reason to use fossil fuels. The fact that we do actually let's us waste a ton of it. If we had to ration it to the bare essentials we'd be able to get away with using only 5% of the energy we currently use. Our current solar energy production in the United States is 2% but that 2% would have been more than enough to power the entire country in the 1920s.

Wishful thinking with no basis in reality. If we couldn’t use coal, we would cut down and burn trees unsustainably long before we magically manage to invent renewable energy tech without all the benefits of modern infrastructure.

> There's really no reason to use fossil fuels.

Except for the critical dependence on them in almost every aspect of the economy sure.

> If we had to ration it to the bare essentials we'd be able to get away with using only 5% of the energy we currently use.

And how exactly are supposed to organize society into this perfectly energy constrained system?

Maybe future squid civilizations will mine plastic deposits.

There were plenty of dangers. One such threat could be the reliance on charcoal (burning trees) for high heat tasks like smelting metals. If you don’t have coal you’re gonna have a tough time making something like steel in an economically viable fashion. You will, in time, run out of trees to burn. And no, comparisons to modern day don’t count. You need to discount our ability to import tree biomass from other areas against the dependence on fossil fuels that enable that cheap transportation of goods.

Would ot be more difficult? We are yet to feel the fill impact of climate change. Its certainly possoble.

By 200 BC, simple wind-powered water pumps were used in China, and windmills with woven-reed blades were grinding grain in Persia and the Middle East.

The first practical electric car was built in 1890

Climate change is an existential threat. That doesn’t mean reed blade windmills are a viable substitute for fossil fuels.

It is utter nonsense to think you could have fueled human growth with such technology to a remotely similar scale.

Without fossil fuels you have no cheap transport fuel, no green revolution, no industrial revolution, many many metals, plastic, and probably many more things.

I am just pointing out that your measurement as growth might be amazing today, but if, for arguments sake, it is followed by catastrophic collapse, then maybe the schenario without fossil fuels which gives you 'slow and steady' growth could come out ahead at the end of the day.

We might face catastrophic collapse, but that doesn’t mean a slow and steady approach would work. Lack of coal just means you burn up less efficient resources to try and replace it. It wouldn’t be enough. Mostly that means trees. There is no slow and steady. It’s still a race to consume. You’ve just taken out the most plentiful and valuable energy resources humanity has been blessed with.

This view does not require any fondness for fossil fuels now, though realistically we are still highly dependent on them.

"There is no slow and steady. It’s still a race to consume"

Britain ran out of Trees to consume like a thousand years ago, they have records of forest cover since year 1000 and it's between 15-5% ever since.

The cocept of forest management and 'you don't chop down the last tree' is over a thousand years old.

What is the race to consume after trees?

You have no choice but to harness wind, which can actually cover humanity's energy demand, and to use electricity to create fuels and to refine metals. These technologies are over 100 years old. We would be poorer,it woupd be more difficult, but thos alternative scenario doesn't lead to sudden collapse - atmosphere is a unique resource thats impossible to own.

(same poster as above, alt account, sorry)

You're just handwaving history without any real knowledge of how resources developed.

The ability to not chop down trees is predicated on having substitute goods available. One of the biggest and most important innovations the world has ever seen was the invention of iron produced from coke (coal). Before coke, you needed charcoal (trees) to produce iron. It was expensive, and the supply of wood was running out. You mention England. Well England lost 66% of its wood supply between 1000AD and 1900AD at a fairly consistent rate, before widespread use of fossil fuels. This INCLUDED needing to IMPORT large quantities of wood from other areas. Its great that they've managed to reforest their local area, but the net consumption of wood on a global scale is undoubtedly still net consuming. And if we never used coal to make iron, then the economic cost of literally everything just got much higher, and more expensive, and more wood intensive. Learning to make iron from coal allowed us to stop using wood as a substitute. To be clear, the industrial revolution is just not economically viable to happen without coal. Society just does not advance. It's not a matter of putting up windmills.

Without fossil fuels you don't get iron, steel, plastic, etc. You know what wind turbines are made of? Steel. Iron. Plastic. Mostly steel. You can't make steel without fossil fuels. Aside from the massive energy requirements, you're going to need coal in there to get carbon into the steel. Unless, yet again, you want to burn trees into charcoal.

Even with today's tech and substitutes, deforestation continues at an alarming rate. Dropping us back to pre industrial revolution tech isn't a good idea to solve that.

Ultimately, hydro power depends on oceans supplying abundant water vapor to precipitate over elevated topography. No oceans, no hydro power. You also need topography: no land, no hydro power.

Sure, whatever. Tidal energy is still not hydro power, but rather a separate thing.

Nobody said tidal power was hydro power. But, for completeness, I will say it now: tidal is also hydro.

It is distinguished from common hydro power by drawing, ultimately, on planetary body kinetic energy rather than insolation.

Well that’s not correct. You can say whatever you want but that isn’t the common definition of the term.

Language is tricky, and cannot be made less tricky without loss of most of its value.

Most fossil fuel deposits formed during the carboniferous period which would have been quite ancient even to the dinosaurs. One of the clues that an intelligent civilization never arose before us is that those deposits are still here for us.

Or that we're the only ones dumb enough to use those resources instead of leaving them on the ground and utilize much more accessible and renewable resources instead.

We ARE using the most accessible and economically efficient resources (coal and oil). The only reason we even have the phrase "renewable energy" in our vocabulary is because we were able to advance our civilization thanks to coal and oil far enough, that we can worry about the consequences and their mitigation.

The only evolutionary leaps to suboptimal energy production that I'm aware of occurred in cases where a more efficient energy source simply doesn't exist (eg geothermal vent communities on the ocean floor).

One would hope that fossil fuels are just a quick step in the technological bootstrap process on the way to clean/renewable energy, though I agree it's not looking too good at the moment. My guess is they are necessary though in order to go from pre-industrial to more advanced. Despite the negative externalities, the amount of energy they contain that is easily unlocked is remarkable.

Do you think humans have been at their current level of technology forever?

Why? We're only using all that fossil fuel for 100 years or so...

Maybe there were multiple intelligent civilizations before humans, then the Great Filter Theory kicks in and they wipe themselves out with Global warming or whatever.

I have a pet theory (just a fantasy really) that Dolphins were once land mammals with an advanced civilization but then they too heated the planet up until all the ice melted and they had to adapt and evolve to be sea mammals.

Afaik we don't see any geological evidence of such a thing

I mean, it's true that dolphins evolved from land mammals.

Sounds like something Douglas Adams would write.

Or something Kurt Vonnegut did write (Galapagos).

Thanks!

The only answer to such questions is "there's no way to know." Which implies that selection bias is the best we can do.

Ultimately, we're here. And we may only be here because we genocided all the other proto-human races (at least four of them). But no one likes talking about that, since it seems much more... personal... than a meteor.

Was it intelligent to slay the neighbors? Maybe. But it was a comparatively rare event, since once it was done, it couldn't be done again.

The interesting thing is that there's no way to know how many events like that have happened throughout all of history. We have very little data compared to the entire timeline. So any kind of measurement of "If this, then that" is very hard, and I have serious respect for the careful work that scientists manage to do in spite of the limitations.

By the time I was done with school, subgroup dominance was shared among jocks and punk kids. Previously, it seemed that jocks were the most admired. After my time in school, the shift towards "weird and smart" kept increasing, to the point that bullying is now anathema and kids seem much freer to express their non-normie views.

I think this is a micro example of a tendency for people to value raw physical power over mental faculties, and how it eventually shifts as the environment changes. On earth and elsewhere, there may be species that evolved to dominate through power, snuffing out those with the potential for dominating through intelligence. I agree, this might be one of those filters that are hard to surpass. For example, by sheer luck, dinosaurs were wiped out leaving room for mammals to take over the planet. Could dinosaurs have evolved to discover computation?

On an intraspecies level, we breached a similar filter when we began organizing into agricultural/specializing societies. Those societies were started as a way for the physically powerful to harness lower-status humans. The consequence was the emergence of information-societies where intelligence is more valuable than physical power.

> Could dinosaurs have evolved to discover computation?

At least judged by brain-case, (predatory) theropods would have been on the upper-end of dinosaur intelligence. Therefore we have that birds/avian dinosaurs are descendants of possibly the most intelligent branch of dinosaurs. Birds had as much time as mammals to evolve a candidate for human level general intelligence but never did. The most intelligent dinosaurs† that have ever evolved seem to be Parrots, Crows, Ravens and their close relatives.

Though bird brains (IMO) are better designed, able to keep up with higher primates using fewer more densely packed lower energy neurons, they do not match later homininans in generality.

-----------

†The Silurian hypothesis essentially observes it would be extremely difficult for definitive evidence of a past advanced civilization to persist for longer than 10^6 to 10^7 years. It also notes that it's more difficult than one would naively assume to rule out the possibility of an advanced civ based on the geological record.

It's unlikely to be correct however. I went into more detail in this post: https://news.ycombinator.com/item?id=29514626.

There were some very large mammalian predators around during the time of our early ancestors, and even around today, though not quite as large. And yet here we are. Perhaps if humans had arisen in the time of the dinosaurs they’d have hunted them to extinction or destroyed their habitats.

Intelligence evolving before humans doesn't refute or contradict anything about this article unless it evolved independently on a different branch from humans.

Something like this strikes me as the most likely Fermi paradox explanation. We will probably eventually find other life, but it will almost always be bacteria to at most multicellular life on the order of Cambrian era fossils.

If intelligence occurs at a rate less than say once per galaxy per billion years, we may never meet ETI. Might find lots of bugs though.

Intergalactic travel is many orders of magnitude harder than interstellar travel. The time frames are insane even close to light speed. Over millions of years things fall apart at the molecular level. Building anything that could last that long, even dormant, would be far beyond any technology we can foresee.

> Intergalactic travel is many orders of magnitude harder than interstellar travel.

Andromeda is about 25 galactic widths away. Our galaxies width is about 25,000 times the distance to Alpha Centauri. Alpha Centauri is about 266,000 AU from our Sun. Relatively speaking, the galaxies are quite closely bunched together, compared to their own mind-boggling sizes.

But AU probably isn’t a good way to compare this.

Sun and the Solar System is 1,921.56 AU in diameter (google)

So in these Solar System Units Alpha Centauri is only ~140 SSU away. Still more than 25, but comparable, and we are not in a dense neighborhood, afair: https://astronomy.com/magazine/ask-astro/2006/01/how-close-c...

M15's center packs approximately 4 million stars per cubic parsec — that's more than 75 million times denser than the region around the Sun

But some galaxies pack stars even tighter. M32, one of the Andromeda Galaxy's satellites, has the highest measured stellar density of any nearby galaxy — around 20 million stars per cubic parsec in its core! Not even HST can resolve M32's core into individual stars. A typical stellar separation at this density works out to 0.008 light-year, or 500 AU — about 12 times the Sun-Pluto distance — between stars.

(500 AU being ~0.25 of our “SSU”, or 12 M32’s SSU)

We don't even need to travel to it. We can just wait a few billion years for it to come to us.

Of course, that raises the question of why some civilization with a billion year head start isn't here yet.

Wake me up when we get there.

Even if a galaxy is 10 million light-years away, you can get to it in 1 month of proper (spaceship) time, if you travel fast enough. This is time dilation due to special relativity.

That would be fine if you did not mind colliding with intergalactic medium at lightspeed for two million years.

The term "erosion" seems inadequate.

By close to light speed I meant maybe 50%. You are right if you get much closer, but there are some huge problems you get too… like having the cosmic microwave background blue shifted into gamma rays or the fact that a dust particle will annihilate you.

I have wondered about the Alcubierre drive and similar concepts. Even if FTL is impossible due to causality protection principle issues, these may provide a theoretical way to travel at light speed (effectively) without the above issues. But we are talking very far future tech with outrageous energy requirements… if it is possible at all.

>like having the cosmic microwave background blue shifted into gamma rays

This is patently false.

It is indeed true that a relativistic spacecraft would see a highly anisotropic microwave background: a strong blueshift in the direction of travel, a strong redshift in the opposite direction.

But at 99.5% of the speed of light, the blueshift factor is only about 20. This would shift the 2.7 K microwave background to a temperature of about 54 K; that is still pretty darn cold.

But the example being replied to was going from 10 million years to 1 month, that’s γ = 1.2e8, so β ≈ 1 - (3.4e-17), so blueshift factor ≈ 2.4e8.

I think that means the wavelength goes from 2.7 K ≈ 1.07mm to 4.46pm. Is a blackbody spectrum still a blackbody under Lorentz transform? If so, 650 million K?

> like having the cosmic microwave background blue shifted into gamma rays or the fact that a dust particle will annihilate you.

But doesn’t this imply that there is preferred reference frame in the universe?

Kind of yes but also not really. The important thing is that the laws of physics are measured the same in all inertial reference frames. Consequently there is no non-contradictory sense in which an experiment could distinguish an absolute rest from other inertial motion. It's therefore not possible to talk about motion under constant velocity in an absolute sense, it must always be in relation to something else.

Any other body could have been chosen as a (relative) rest frame but the CMB is uniquely convenient to coordinate measurements with due to its age and the extent which it permeates the universe. Physics is still the same in that frame as any other inertial frame.

Not in terms of the laws of physics

If this is true you just lit a candle in my internal temple of hope lol

In the Earth time, the spaceship would take a bit longer than 10m years to reach it, however. Plus the energy required to reach such velocity would probably be more than mass of the Earth if we were to annihilate it.

Well, accelerating a 100 ton spaceship to 0.99c (assuming some sort of beamed propulsion) requires only 2000 Terawattyears [1].

Of course, to turn 1e6 years into 1 year relative time, one needs like 0.99999999c, one needs 2 million Terawatt years [2], which is a much bigger energy investment, but still not on the order of annihilating the planet.

Breaking is gonna be a bitch tho.

[1] 100000 kg * (0.99 * c)^2 / sqrt(1-.99^2) in Terawatt Years

[2] 100000 kg * ( 0.99999999 * c)^2 / sqrt(1-0.99999999^2) in Terawatt Years

Braking? Spend half the trip accelerating, the other half decelerating. The "erosion" problem mentioned nearby is still formidable.

Natural or directed panspermia completely changes the nature of this discussion.If evolution occurs at the galactic scale then we can greatly raise the odds that we are among the first civilisations.

Research von Neuman probes

If you find a german tank with a serial number 200, your best guess of the total number of tanks they have is 400.

With the same logic, we can guess that civilizations that discover nuclear power live around 150 years.

I believe, that logic should be different. When you consider tank, you assume that some random process of sampling took one tank out of all tanks that existed from start to end. The reasoning assume that you might get any tank, with a serial number 1 or 500 or whatever. Any existed number.

When you look at civilisation with nuclear power, then sampling process had no chances to took civilisation existed for 120 years. Even if civilisation could live for 120 years. It is a different process of data generation, so the reasoning must be different.

probably not rare, but the combination of having opposable thumbs and being able to collaborate is unique. crows, dolphins and magpies are intelligent, so are apes, dogs, cats, and even insects. the question is if we're smart enough to recognize that intelligence. we perceive animals as more intelligent if we can can find a way to interact with them. measuring intelligence is in itself a non-intelligent thing to do

Koalas have two opposable thumbs, in a parallel universe just imagine how the civilization would be build by them. They would need to be much more social and have a bunch more time over than just sitting there digesting food. We freed so much of our time and metabolic needs just by cooking meals - it's insane. What I'm getting at, there's so many factors that we never even consider.

Or we might get Ob'enn (I heavily recommend the attached comic universe) https://schlockmercenary.fandom.com/wiki/Ob%27enn

We perceive animals as intelligent if they’re good at interacting in complex ways with their environment to get what they want, in novel situations.

Like if you were to trap a human in an alien maze with some food in it and a viable way to get it, the human would improvise rather than starve, demonstrating intelligence.

One could argue stoically accepting fate and not playing the alien’s game is also intelligent (like in Star Trek).

But we work with what we have.

For me intelligent life should be from somewhat to very common across the universe.

Simplistically you would need:

A source of energy, aka a star, at the very least there are 10^22 of them

A rocky planet situated in the habitability zone of the star (and this is lacking the imagination for life in other kind of environments).These guys are common.

The creation of chemical self-replication with a stable set of compounds (The hardest part for me, but far from impossible)

The appearance of intelligence as an evolutionary trait (nature loves that explore/exploit game)

Time

We modern humans lived 99.7% of our 200k year history entirely unaware there were other people and land a mere "earth radius" away, we may as well repeat that story in a cosmic scale.

You should read the article. They are making the same kind of argument as you, but more carefully.

In particular, the key logic is: either intelligent life takes much longer to evolve than stars’ lifetimes, or about the same, or much less. We evolved at about 80% of Earth’s habitable lifespan. That would be very unlikely, if on average intelligence took less time to evolve than star lifetimes. Taking the same time on average is a knife edge case (I think this depends on the multiplicative nature of the probability distributions involved). So probably it is more. In which case, life is very rare.

The problem is really that we spent 99.7% of our history extremely close to the surface of an extremely large sphere. Space is somewhat less lacking in, like, physical obstacles. I mean really, a priori, if there were loads and loads of intelligent species in our galaxy, wouldn't you expect to see them? Why bother positing a brand new set of technologies that just by chance happens to thread whatever needles are necessary to avoid detection, and just figure "oh, guess for some reason there are fewer technological civilizations than I expected"? Obviously we aren't alone in the universe, but it takes some real gymnastics to justify nearby neighbors.

> I mean really, a priori, if there were loads and loads of intelligent species in our galaxy, wouldn't you expect to see them?

Not according to the Dark Forest theory. There are either quiet civilizations or dead civilizations due to realpolitik. This video summarizes the details[1]

1. https://www.youtube.com/watch?v=xAUJYP8tnRE

We can't see Planet Nine right under our nose, why would we see anything beyond that?

Yeah I think our level of intelligence is probably pretty rare. I mean we have a G type star which are not that plentiful in the cosmos. We have a large moon that causes tidal forces on earth and mixes things up. We apparently have a nice selection of elements in our solar system. The problem is that humans took a very long time to evolve. Now we only have .8 billion years to enjoy things before the sun cooks the planet.

I think we have much less, before someone fucks up.

I love stuff like this, in the past I spent a good amount of time wondering about what were the key milestones in the development of intelligent life. Multicellularity is a good example. From my (admittedly outsider) perspective, a lot of that seems lost on the popular approaches to AI, which seem to focus too heavily on the late-stage result (the brain) and not everything that led up to it. Evolutionary algorithms have been out of vogue for some time, Artifical Life is an under-explored backwater.

One thing that I am surprised has been left out of this analysis is extinction events. In the intro it seems to dismiss “models that appeal to rare chance events” (paraphrasing). But the Cretaceous-Paleogene extinction in particular was a chance event that had an absolutely massive...impact...on the evolution of intelligence. Dinosaurs dominated for a couple hundred million years with no signs of moving toward primate-style intelligence, and then suddenly a whole new set of conditions created an environment where scavenger mammals developed rapidly.

I'd say that the big milestones would be photosynthesis, eukaryotic life, and then multi-cellularity. I trust the first and last are obvious but I think people don't appreciate mitochondria enough, for all the memes about "the powerhouse of the cell". Bacteria respirate over their membranes which, through the square-cube law, limits how big they can be. Our cells have many mitochondria scattered though them and can get pretty big. And with size comes the possibility of much larger genomes. Plus in life on Earth at least mitochondria are responsible for apoptosis and its hard to image multi-cellar life without that.

If you replace "intelligence" with "flying", it becomes more apparent why there is generally little interest in artificial life as an approach to develop artificial intelligence (although there are small conferences on this approach).

In general, to recreate something from nature, so far we have not needed to recreate nature as a whole. It is not clear why we need to treat intelligence any differently.

For one, flying is a relatively simple physical phenomenon, and once we had a firm grasp on the principles of lift, we were able to design our own solutions.

Intelligence is, in comparison, an incredibly complex phenomenon that seems a lot harder to separate from the inner workings of the biology and evolutionary history. It feels to me like there is an implicit hubris embodied in the industry and reflected in your comment. Obviously there has been an increasing overlap between neuroscience and AI, and the approaches do strive to understand and mimic the biological structure of the brain. What is not clear to me is how we have largely collectively decided that we don’t need to incorporate understanding of how that structure came to be.

And I’m not saying that we need to replicate the whole process exactly as nature did it. That would take billions of years. But perhaps if we understood it better we could take the key insights and mechanisms to design our own system.

Intelligence is more than just processing information. A big part of intelligence is agency, it’s having a reason for doing things because you live in a world where you have intrinsic goals and desires and feelings and needs. I just don’t see AlphaGo or Watson or anything like that ever reaching that level. They’re Frankenstein vat processors built to answer questions within predetermined contexts we bake into them. They’ll never question why they do what they do or simply decide to do something else. I’m convinced we need to essentially create a simulation where something with agency can develop on its own in order to reach truly interesting AGI.

> I’m convinced we need to essentially create a simulation where something with agency can develop on its own in order to reach truly interesting AGI.

That is fair, and some people do work in that direction. However, the step from "can develop on its own" to "will develop on its own" is highly non-trivial. And seeing the results from the really smart people that work in this direction, I am very much not inclined to work in that direction. There simply does not seem to be a good way to make progress.

> Intelligence is, in comparison, an incredibly complex phenomenon that seems a lot harder to separate from the inner workings of the biology and evolutionary history.

You might claim that now, as we don't understand intelligence yet. However, in the same way it was claimed in the 19th century that people would never be able to fly. What I meant to say is that things that seem hard in nature, might actually be a lot simpler in technology.

I actually don't believe that intelligence is an incredibly complex phenomenon. On the contrary, I reckon we are really close to cracking it. I put it on the same level as moon-bases and nuclear fusion, all reasonably likely to happen in the next 20 years.

However, the step from "can develop on its own" to "will develop on its own" is highly non-trivial.

Yeah, that's the rub. When starting from a more primordial level, the search space is widened to truly astronomical proportions. It may run for ages before you can even tell if progress is being made. I understand that this is not attractive to many researchers/investors. I've often wondered how one would go about crafting a viable fitness function and admittedly I've not come up with much.

What I meant to say is that things that seem hard in nature, might actually be a lot simpler in technology.

Fair enough. I don't believe that intelligence has to develop the way nature did it on earth. It is plausible that there is a way to short-circuit it like we did with flight. But it's not guaranteed that we're on the right track to finding it either. I would just love to see more research along those more experimental evolutionary lines.

From the abstract: "The emergence of intelligent life late in Earth's lifetime is thought to be evidence for a handful of rare evolutionary transitions".

---

How do we know it is late in the Earth's lifetime? What if this is early?

We know we're at the second half of Earth's life history because life has existed since the very beginning, at least 4 billion years, and it's widely believed that within 1 billion years from now, due to how the Sun will evolve, life will become utterly impossible [1]. Maybe the technology a highly evolved civilization can create could stop that, but given how things are going, that's extremely speculative.

EDIT: correction: by 1 billion years from now, the oceans will be mostly gone and likely animal life will be impossible, but unicelular life will still be possible for another few billion years, according to the linked article... "By 2.8 billion years from now, the surface temperature of the Earth will have reached 422 K (149 °C; 300 °F), even at the poles. At this point, any remaining life will be extinguished due to extreme conditions.". Mind blowing.

[1] https://en.wikipedia.org/wiki/Future_of_Earth#Loss_of_oceans

It exists only where God allows it to exist. Some intelligent life forms are separated from the rest by vast stretches of space and time, others are not. Each one has a special reason for existing.

care to explain more? "because my preferred choice of suoernstjentity says so" hasn't held up well as a scientific argument

There are a countless rare transitions that we don't yet even recognize as important, each of them compounds the rarity of technologically advanced intelligent sapient sentient life.

Rare at scale is not rare.

Nice work of science fiction. It is impossible to estimate the probability of these events with a sample size of one. It likely took billions of years for our planet to reach the right temperature and composition for life to form. It's probable that life readily forms given the right conditions. In my opinion, it makes more sense that it is rare for a planet to develop the right conditions for life. That doesn't really matter much given there are 700 quintillion planets in our universe.

With bayesian probability a single observation can be informative (in the sense that a single observation leads to a change in distribution over hypotheses or parameters). It's a matter of narrowing down beliefs on weighted possibilities though, not a definitive answer on the state of reality.

The author doesn't rely on observation. They propose combinatorial models, obtain large time estimates and notice that observation is consistent with these estimates because sample size one, it's a coincidence.

You raise good points but the following:

> It likely took billions of years for our planet to reach the right temperature and composition for life to form

.. is not true. As mentioned by Wikipedia below, life formed surprisingly "fast" and its earliest appearance is pushed back every year.

> The age of the Earth is about 4.54 billion years;[49][50][51] the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago.[52][53][54] Some computer models suggest life began as early as 4.5 billion years ago.[4][5]

From Wikipedia https://en.wikipedia.org/wiki/Earliest_known_life_forms

> It's probable that life readily forms given the right conditions

Is this true? It is it also impossible to know?

We haven't been able to reproduce it, so is your argument that we just haven't gotten the conditions correct?

An argument for life being expected is made pretty well in the book "At Home in the Universe" by Stuart Kaufman (spelling?).

We the expected.

The Miller-Urey experiment produced over 20 different amino acids, the building blocks of life.[1] Scientists think the first cells developed from chemically active water droplets.[2] I'd argue we have reproduced it, there just isn't enough time to be sure.

[1] https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment

[2] https://www.quantamagazine.org/dividing-droplets-could-expla...

Statistically speaking, if it happened on our planet, it can (and likely has or will) happen elsewhere. Given that there are approximately 700 quintillion planets in the observable universe, it seems sensible to expect it to be mathematically possible and even likely that it has also developed elsehwere.

For all we know, there were space fairing civilizations in or around Alpha Centauri. Maybe they were killed in a cataclysmic event a billion years before earth was formed?

> Statistically speaking, if it happened on our planet, it can (and likely has or will) happen elsewhere. Given that there are approximately 700 quintillion planets

But numbers can go as low as they please, statistically speaking. It’s not like “1 in a billion” is the lowest possible probability. What if there are 700 quintillion planets and the probability of life evolving on a planet is 1 in 700 sextillion and we just got really lucky?

It's certainly possible but you've also chained a very specific series of events to explain an observation. Such scenarios are most hygienically reasoned about using a Bayesian quantification and updating of uncertainty. There's a lot we don't know but from what we do know and the observations we've made, life is likely to be extremely rare.

I agree with all of this, but I don't think any of it makes the GP statement true.

It seems likely simply because life came into existence almost as soon as physically possible on earth.

Suppose that life starting is one out of multiple hard steps needed for us to exist. And there's a deadline of perhaps a billion more years before we could never exist, if we didn't occur by then.

Then the early appearance of life is not evidence that life happens easily: all of the hard steps have to happen 'quickly' relative to how long they would 'naturally' take, or we wouldn't exist to observe this history.

I think the paper explains this logic, going by the abstract.

All of these discussions seem to hinge on the assumption that intelligence arises spontaneously from nature given the "right" conditions, but that is an unproven and statistically unlikely assumption [1]. Just as a random byte generator will statistically never output a full featured operating system within the age of the universe (and certainly nothing resembling elegant source code), so are any random chemical/biological/physical processes statistically unlikely to ever spontaneously lead to intelligent life within the age of the universe. Intelligence is created by intelligence, nothing else. Call it "God" or whatever you wish, but it doesn't arise out of randomness, unless the randomness is constrained into highly structured output, which requires intelligence to do.

[1] https://en.wikipedia.org/wiki/Infinite_monkey_theorem

"Your theory that the sun is the centre of the solar system, and the earth is a ball which rotates around it has a very convincing ring to it, Mr. James, but it's wrong. I've got a better theory," said the little old lady.

"And what is that, madam?" inquired James politely.

"That we live on a crust of earth which is on the back of a giant turtle."

Not wishing to demolish this absurd little theory by bringing to bear the masses of scientific evidence he had at his command, James decided to gently dissuade his opponent by making her see some of the inadequacies of her position.

"If your theory is correct, madam," he asked, "what does this turtle stand on?"

"You're a very clever man, Mr. James, and that's a very good question," replied the little old lady, "but I have an answer to it. And it's this: The first turtle stands on the back of a second, far larger, turtle, who stands directly under him."

"But what does this second turtle stand on?" persisted James patiently.

To this, the little old lady crowed triumphantly, "It's no use, Mr. James—it's turtles all the way down."

— J. R. Ross, Constraints on Variables in Syntax, 1967

This joke actually highlights the utter ludicrousness of a scientific-rational explanation of the universe without God. Because as long as you keep searching for "phenomena" to explain existence, the question remains, what caused that phenomena. But "God" is a sort of final answer to the problem, a realization that causation has to stop somewhere, and wherever it stops, that is God.

Since it's everything but random, given the strong, strong selection pressure, what you wrote misses the point completely. And the argument based on that is completely meaningless as well.

What creates that selection pressure?

What counts as intelligence though? Worms? Fish? Cats? Apes? Humans?

Why not all of them? I never said intelligence was exclusive to humans.

They're Made out of Meat!

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