Possible to detect an industrial civilization in geological record? (2018)
cambridge.org
cambridge.org
>but given what we have done to date there would have been time enough to find evidence of a society like ours
Geology is a relatively young science. Today's widely accepted facts were laughed at only a few decades ago. Take Wegener's plate tectonics theory: He was ridiculed for it and it only started to become mainstream accepted opinion among geologists after his death, around the 1960s. Your grandparents may still have been taught the land bride idea¹ when they were kids, which nowadays is seen as extremely ridiculous. Yet many today, who may not consciously be aware of these developments, assume that science™ has always known this and that we basically understand earth. We've barely started scratching the surface, in the literal sense.
As for hypothetical civilizations lost millions of years ago, there is no way one can rationally claim to know for certain, it depends on so many factors. The Silurian is merely an example, since this is a thought experiment. It could have been much longer ago, it's speculation. But let's assume Silurian it is, and let's say plastics would stay detectable that long (we don't know this for sure). All you have to have is a civilization that didn't invent them, or didn't widely use them. And no nuclear bombs either - hardly inconceivable. Though as an aside, the half-life of Plutonium-239 is only around 24k years! So good luck detecting that.
¹ https://people.wku.edu/charles.smith/biogeog/pics/sim1940e.j...
Then is there any science culture today that isn’t dysfunctional?
Any grad student can point to 5 professors who would ridicule plausible ideas.
Tobacco funding research to prove smoking is healthy.
> The biggest issues with non replicable science are all in academia which is grant funded.
Yes, that was his other point, politically charged topics are bound to create bad science. So things related to poverty, intelligence, gender, race, education etc.
The pathway to profit for medicine is getting the FDA to approve your drug. This should only happen if the drug works, but the way the FDA determines that is by the data and studies you give them. Well at least in theory, there's also complete nonsense like aduhelm where the FDA even approved a drug their own medical panel concluded didn't work, leading to mass protest resignations. [3] That's probably an argument against shenanigans (why even bother?), but I still think it's relevant just to emphasize how dysfunctional our medical regulatory system has become.
[1] - https://en.wikipedia.org/wiki/Replication_crisis#In_medicine
[2] - https://www.taconic.com/taconic-insights/quality/replication...
[3] - https://www.nytimes.com/2021/07/19/health/alzheimers-drug-ad...
Of course most of our oil reserves come from the Mesozoic age (66-252 million years ago) so either the Silurians quickly transitioned away from fossil fuels, or blew themselves up and went extinct before they could extract all of it.
- evolutionary evidence pointing at the possibility of species with large enough brains to build industrial civilizations
- sedimentary proof of artificial pollution and CO2 levels
- fossils
Any hypothesis has to be proven to be true, proofing it to be wrong is impossible and not things work. What the cambrisge paper did, was pointing towards wayw to proof the existence of an ibdustrial civilization millions of years ago. Now the work is on the people believing that theory to proof it.
Speculating without considering the basic principles behind said claim, concluding it is impossible to proof that theory wrong and finishing all that off with a the claim that such a civilization most definetly did or could have existed is just stupid. It worries me so, that this kind of shit shows up on HN more and more often.
That's pretty much entirely how science works ever since Karl Popper: You find an observation that the hypothesis cannot predict or predicts wrong. Bam, hypothesis falsified and rejected, no matter how much positive proof was uncovered until that point.
Or, if you like, find and show proof making the existence of such a civilaztion likely. And no, the burden of proof is not on the side diaputing the claim of such an civilization, as only the existence of something can be proven, not the absence. Hence the very exact formulation of any null-hypothesis.
Coming back to some pre-dinosaur industrial civilization (why stop at industrial so, why not an instellar one?): there is a ton of data and samples from that time periods (litterally reaching back hundreda of million of years), so everyone trying to find evidence for such a very bald claim has a lot of data to work with. Just putting out the claim and saying it must be true brcause nody can proof it wrong is not how things work, in reality that is, on the internet everything goes apparantly.
One example of those - Intact fossils are very rare, and life has been ever present on the surface of the planet a billion+ years, near as we can tell.
That said, unless they weren’t around for long or didn’t have much success/impact, some difficult to dismiss evidence would likely to be present somewhere we ran across already - like fossils. Even if 99.99999% of all our evidence gets subducted, anyone doing as much digging 50 million years from now as we’ve done recently would have a hard time missing all of traces we’ve left.
A really weird set of isotopes and geological features (like in Oklo, but not explainable naturally) from something like the National Test Site, or a layer of something like lead or mercury or radioisotopes in the sediment record not explainable by other means (like we’ve left), or a landfill full of plastic+stainless steel+carbon since metamorphized, or weird geological features like road fragments with no plausible natural explanation.
So unlikely, but not impossible. We are talking lengths of time 1000x (approx.) the furthest back of our own artifacts we’ve found.
Places like alexandria have a ton of history under the city that can't be explored because people live there now but what if what people were building on top of 2-3k years ago was on top of a ruins that existed millenia before their time?
When you find roman ruins for example you would stop digging right?
Would it be possible to detect an industrial civilization in geological record? - https://news.ycombinator.com/item?id=24601375 - Sept 2020 (178 comments)
The Silurian Hypothesis - https://news.ycombinator.com/item?id=21840320 - Dec 2019 (52 comments)
> We name the hypothesis after a 1970 episode of the British science fiction TV series Doctor Who where a long-buried race of intelligent reptiles ‘Silurians’ are awakened by an experimental nuclear reactor.
> We are not however suggesting that intelligent reptiles actually existed in the Silurian age, nor that experimental nuclear physics is liable to wake them from hibernation.
We can barely detect human activity from 50 years ago when we know exactly where it is.
I think we are More likely to spot ancient Geostationary satellites, which will have drifted away from a perfect circle but should still be noticeable. LAGEOS aren’t in anywhere near that high an orbit but should survive 8 million years. They have a plaque on them designed by Sagan should a future civilisation find them.
A similar civilisation may have gone to the moon, but thanks to irradiation and micrometeorites over millions of years. Footprints and tyre tracks would certainly be gone, and while you could land at an Apollo landing site and detect remains of refined metal, it’s unlikely to be something you could see from orbit with our level of equipment, you’d have to get up close and personal, and we haven’t done that.
In other words, it was specifically protected from the elements, in a way intended to be detected only by a species at a certain minimum level of technological development.
And just like the paper, it acknowledges the challenges in detecting such evidence due to the limited and complex nature of the geological record.
https://www.un.org/sustainabledevelopment/blog/2019/05/natur...
A refreshing conclusion to an academic paper, and beats the hell out of "further study is needed."
https://en.wikipedia.org/wiki/Iridium_anomaly
The article mentions 244Pu and 247Cm, but ruthenium is produced in larger quantities and is stable.
I am really curious what kind of sign you envision will survive that onslaught.
Something like diamond plaques with writing on them, maybe just reuse what we put on Voyager but in different materials.
I bet there's a better material than diamond, not sure what though. You'd want something that lasts, but not something that can be reused. Eg don't use gold, someone will melt it down later...
Plastics? Micro plastics?
Humans have been around for a frw hundred thousand years (if you're generous). Our current traces will be gone in a few million.
Just because something doesn't visibly keep disappearing in front of your eyes doesn't mean its some ultra stable form to last for a billion years.
Also, one proper earthquake and your fine stone structure is a big pile of rubble. Now do it 100x.
During the last 2.6M years - and man's been around -at least- that long - there've been a dozen or two ice-ages. Between them were interglacials, some of which lasted 2 or 3 times longer than our 10,000-year holocene. More than enough time and resources for an earlier (even wiser or saner) humanity. Or three.
"Our historians say it is the genitalia of a species who lived in ancient times."
;)
Replace as many plants and animals as we can with genetically engineered versions that have messages encoded in their junk DNA.
That would not be good enough to tell aliens who visit long after all life on Earth has gone extinct that we were here, but could work for future intelligent species that evolve from existing Earth life after humanity is long gone.
Also, while I was using hundreds of millions because that was the timeframe of the original question, the reality is that we actually have fossils that are more than 3 billion years old.
The next civilisation doesnt get like a perfect 3d scan of the entire planet, kilometers deep. They get sporadic evidence that they happen to find
Artifacts that would have been used by these civilizations, whatever those may have been.
It's late and I couldn't come up with something that'd survive the timespan in question, so I just wanted an example.
You may have confused geology with archeology, they operate on completely different time scales.
The difference between a coin lasting a thousand (10^3) years and 100 million years (10^8) is five orders of magnitude.
That's the difference between 1,000 years and...3 days.
"I collect sandwiches. I have some that are 3 days old and in excellent condition. I expect that in the right conditions one could last 1000 years"
What would only 10000 years more of that have done to it?
(also, hi nemo! Found you. :P)
This youtube video addresses the situation pretty well - I found it very interesting the talk about the earths crust basically recycling.
a planetary apex species capable of industry would have funerary rituals to prevent anything from learning a taste for their bodies. their dead would be well protected from harm if they weren't already somehow destroyed, and this would probably prevent any form of fossilization to be found later.
even assuming you can't find their biological remains, you might expect to find metals they had used, perhaps within a similar context that we find fossilized remains already. an unnatural combination of metals under some soil.
i've seen one conspiracy-like youtube video of this[1]. i haven't seen any other sources and i doubt this is real. even if it sounds cool conceptually, the video gets a little over the top in craziness, especially for something that has basically zero sources but would be widely known if it were true.
based on my limited understanding of these chemicals, things like gold, platinum, titanium, would likely be left over in a relatively non-degraded state.
and if legitimate traces could be contemplated, for any tests based on organic elements i would expect a kind of signal compression or expansion to happen in the soil over time due to pressure, diffusion, and potentially something like moisture.
That seems to be making a lot of assumptions. Why couldn't tossing bodies into a tar pit be a funerary rite?
its a nice idea, but its technically putting the cart before the horse as those pits wouldn't have been around due to them being formed from decaying organic matter from that time. if you're trying to say those could have been locations where those rituals might have taken place, i suppose its fair enough to ask that, to test it you could check the locations and crude grade of all currently known oil locations, and if you manage to find similar grades on land as you find in the middle of the sea, especially in locations that were never land to begin with or weren't land during those time periods, then that would disprove the idea because they wouldn't have made tar pits in the ocean. there probably other ways to test this idea but this is what i have off the top of my head.
Oil is not primarily made of dinosaurs but rather of plankton and algae.
>its a nice idea, but its technically putting the cart before the horse as those pits wouldn't have been around due to them being formed from decaying organic matter from that time.
You're talking about 100 million years ago as if that's a tremendously long gap but glossing over a span of about 400 million years as if it were a single instant. At any rate a tar pit was just an example of an environment that is conducive to fossil formation.
They could practice burning, tossing them into the seas, composting, or even alcalic hydrolysis to be hyperecoligical and environmentally friendly.
This is only true for coal, not for oil (which is formed mostly from sea plankton biomass that is mixed into sediment layers).
Similarly while trains needed fossil fuels ships didn’t and allowed for very efficient transportation of goods on the ocean and inland through areas with sufficient rainfall. The major historic use of coal was for heating, but much of the earth never gets that cold.
Additionally, coal wasn’t even used for making steel in the US basically at all until 1827 (charcoal has fewer impurities like the sulfur found in a lot of early coke). The US primarily used charcoal from wood even for iron production until well into the mid 1800s (and by 1884, charcoal was still used for 10% of iron and steel production in the US, and charcoal was still used in some niche areas even into the 1940s). And steam locomotives in the US were also often powered by wood in the 1800s.
Critically, you can move wood long distances so running out locally isn’t an major issue as long as you don’t run out globally.
Your industrial output will be limited, but there's plenty of land and forests grow by themselves.
A large fraction of the early/mid Industrial Revolution was powered by hydro/wood. Abundant rainfall is why so much industry ended up in the north eastern US and England. Efficient motors was more a result of a scientific and industrial innovation rather than the cause of such.
So suggesting Ironworks as a major obstacle doesn’t really stand up.
Almost all of our current hydropower is based on damns made of concrete. Creating the cement for that is very energy intensive. Also turbines and generators are made of metals which require a lot of energy to melt.
Probably you can bootstrap a waterpower based industry somehow without fossil fuels but it is not trivial.
The other thing is that each incremental step in such a process has to provide some benefit to the participants. For example you are not going to have generators without readily available good quality copper wire, but bootstrapping a copper refining and wire making industry without fossil fuels is very hard. Those people need to see a reason for doing it in a world where there is no electricity yet therefore there is very little need for said copper wires.
There’s this idea that the Industrial Revolution ran on coal but Coal was an inferior fuel for steel production until ~1827 or so.
Eventually steam locomotives beat horse / manpower drawn canal boats, but it a close contest until surprisingly recently. Hell the last commercial cargo sailing ship was in use until the 1960’s long after nuclear power became a thing.
Is that really harder than building hundreds of kilometers of aqueducts? Humans have known how to engineer water flows for thousands of years, if we valued power we would build those dams. That power would be more expensive so it would slow down the industrial revolution but it would still happen.
Also you don't need continuous power for an industrial revolution, that is convenient but factories are still revolutionary even if they just run half the year.
In fact, suspiciously, only a small percentage of what exists today is assumed to have been formed in the Paleozoic. If anything the notion that they'd have used up the fossil fuel only supports the idea that such a civilization may have existed, if anything.
But of course one can also point to the simple fact that we're already transitioning to renewables and we're far from being short. We just do it because it's better. So why couldn't a past civilization have done the same?
I read once that stamping serial numbers into steel changes something at a molecular level in the steel, so that filing them away is not enough to remove the number entirely. Maybe we can do that to tungsten.
People have mentioned fossil fuel depletion. These do renew on geological timescales, but there's a minimum bound of when they could have started to accumulate. The reason we don't have fossil fuels going back further than the Palezoic isn't because a far-past civilization may have depleted earlier stores, but because the types of organisms that eventually create fossil fuels didn't exist at a large enough scale until the Carboniferous period, which occurred in the late Paleozoic. There are other possible sources of energy, but none as easily accessible as igniting a high-energy combustible material.
There's the general evolution of bodily morphology necessary for advanced tool creation. Although I am sometimes struck during all the nature documentaries I watch of animals stuck in rough situations where greater intelligence might have helped, I am far more often struck by animals that would have been helped by grasping hands. Among sea-dwellers, you've got the tentacles of certain cephalapods for combining manual dexterity with high-intelligence and that's pretty much it. Even extremely intelligent whales are quite limited in what they can do with tools because all of their limbs are taken by locomotive purposes, whereas cephalapods often move via jet streams.
On land, this requires bipedalism, so when did this first start to show up? There are no bipedal reptiles. Bipedalism in mammals is quite late arriving just because mammals are quite late arriving. It's not entirely limited to apes. Otters can do quite a bit with their hands, raccoons to some extent.
Birds unfortunately ended up needing their wings to fly. Earlier dinosaurs did have grasping hands and likely at least a few of them had pretty decent manual dexterity, but these didn't show up until the Jurassic or so.
Then there is intelligence, and not only intelligence, but the need to learn. Species that develop cultures and highly-adaptable learned behaviors tend to have both longer gestation periods and longer times to reach sexual maturity and adulthood. This makes them more dependent on parental nurture. These are r-selected species, which again, I don't believe includes any known reptiles. It seems to have become a common strategy with mammals specifically because mammals developed the ability to secrete milk, and in birds via gaining the ability to store food they could regurgitate from their stomachs. This allows young to not have to fend for themselves and they can spend years learning all of the complex behaviors required to do something like create a civilization. Neither of those traits showed up until after the K-Pg extinction.
There's the rather obvious constraint that you need to be a highly social species in the first place. Intelligent or not, you can only build a civilization through the coordinated actions of many across large divides of time and space. Social behaviors and division of labor show up in colonial insects and you could even argue they have something akin to civilization, but their small size seems to preclude the level of intelligence necessary for what we would recognize as an advanced technological civilization. Large-scale social behaviors in larger animals has tended to show up for one of two reasons, either because traveling in herds offers protection from predators, or because hunting in packs allows for all to thrive even if only a subset of adults at any one time are capable of acquiring food while other needs to focus on learning, play, or child-rearing. The group intelligence and behavioral sophistication required for herds is not as great as for hunters, so we would probably expect predators to be the ones who might develop technology and civilization. This is again not something we see in reptiles. It shows up in birds and mammals, but also not until after the K-Pg extinction. Some types of dinosaurs very likely hunted in packs and had social communities with division of labor.
Once you have those things, you still need a means of communicating and recording highly technical and specialized information. In humans, this required specific mutations in the linguistic center of the brain and in our mouths and throats to produce language, and these only happened in the last million years. That is, of course, not the only way to do it. Certain whales might have sufficiently sophisticated vocalizations that, if they had the means to invent writing, it might be enough. Some of the chemical ways in which certain types of insects communicate could potentially be far more sophisticated than we could imagine, but again, they're insects and limited in what they can do with extremely small brains. Birds also have extremely sophisticated vocalization capabilities, but can't write because of lack of manual dexterity and they don't show up until after the K-Pg extinction. Reptiles don't seem to have particularly sophisticated communications capabilities as far as we can tell.
This again leaves open dinosaur capabilities we may not be aware of.
All in all, it just strikes me that all of the prerequisites I can think of that have to be present on the biological level show up the earliest we know for sure sometimes in the late Cenozoic after the K-Pg extinction, and well after really, given the need to recover. The very earliest they might have occurred in earlier types of land animals that show the necessary morphological and behavioral traits is the Jurassic. The idea that organisms like this may have actually existed in the Silurian just seems mind-bogglingly unlikely. Forget about the visible effects they may or may not have had on the surface of the Earth or potentially nearby non-Earth bodies. How and why did their entire evolutionary family tree disappear and leave no descendents?
If dinosaur bones and trilobites can last hundreds of millions of years, steel and concrete should also.
Dinosaur bones and trilobites don't last very long. What we find are fossils. Steel and concrete don't fossilize.
Ice core: https://en.wikipedia.org/wiki/Ice_core
Ice core > Ice core data > Dating: https://en.wikipedia.org/wiki/Ice_core#Dating :
> The dating of ice sheets has proved to be a key element in providing dates for palaeoclimatic records. According to Richard Alley, "In many ways, ice cores are the 'rosetta stones' that allow development of a global network of accurately dated paleoclimatic records using the best ages determined anywhere on the planet".[43]
/? ice core samples oldest: https://www.google.com/search?q=ice+core+samples+oldest :
- NSF Ice Core Facility > About Ice Cores: https://icecores.org/about-ice-cores#:~:text=The%20oldest%20.... :
> The oldest continuous ice core records extend to 130,000 years in Greenland, and 800,000 years in Antarctica.
- "Record-shattering 2.7-million-year-old ice core reveals start of the ice ages" (2017) https://www.science.org/content/article/record-shattering-27.... :
> Clues to ancient atmosphere found in bubbles trapped in Antarctic samples
- "World's oldest ice core could stretch back 5 million years" (2022) https://newatlas.com/environment/worlds-oldest-ice-core-5-mi....
What would be a more cost effective way to identify signs of prior civilization?
Read the emissions off in black holes that old, (or rather, black hole accretion disks, which are apparently modified Lorentzian attractors with superfluidity and Hawking radiation)
Fly there and perform multiple geologically and geographically covering miles-deep sediment sample studies,
Fly there and drill ice cores,