8 ms·

The Silurian Hypothesis (2020)

75 points by andsoitis 3mo ago

throw310822 3mo ago
So we have microbial fossils from 3.5 billion years ago, fossilised 300 million year old skin, bones from almost 200 my ago, even actually soft tissue inside a fossilised bone from 70 my ago. Ah, footprints too, the most unsubstantial matter of all: pure shape. That's in addition to all the million other fossils that are so common we hardly care: shells, small bones, etc. And someone is saying there could have been an entire advanced civilization 400 million years ago, large and powerful enough to cause climate change, and that no traces of it would possibly be left? Like, billions of individuals, cities, factories, metals, concrete, mines, wells, roads and bridges and tunnels, stone sculptures!, plastic, waste dumps, farms, agricultural land, billions and billions of artifacts of all materials, most of them entirely artificial. All gone because "nothing resists 400 my" and, "oh btw, check this dinosaur footprint and this fossilised piece of skin, how cool"?
- gorgoiler 3mo ago
  The counter argument: dinosaurs were around for a staggering amount of time, no pun intended. 165 million years is reasonably long enough to ensure they left behind some nests, bones, and a feather or two. Modern humans have been around for more like 0.02 million years. The counter-counter argument is that while we’ve been here for a comparative blink of an eye, we’ve left behind 4 orders of magnitude more stuff than just nests, bones, and a feather or two.
  - throw310822 3mo ago
    Indeed. Did a rapid check on T-rex, just as an example. Was around for max 3.6 million years. Max population at any one time must have been around 20k individuals. We have about 150 skeletons. So current human population is 400 thousand times the maximum T-rex population at any one time. A few decades are enough to produce more human individuals than the entire T-rexes history. We also have the ability to go (and die) pretty much anywhere, so there will be human skeletons in every crevice, depth and environment on Earth. We also produce an absolutely staggering amount of artifacts of all kinds, from plastic straws to giant tunnels and artificial caves. There are zero chances an advanced civilisation on Earth won't be aware of us in 400 million years.
    - T-A 3mo ago
      >We also produce an absolutely staggering amount of artifacts of all kinds, from plastic straws to giant tunnels and artificial caves. Plastic will be gone in ~1000 years, https://www.activesustainability.com/environment/waste-planet-digest-how-long-it-takes-to-decay https://www.activesustainability.com/environment/waste-plane... tunnels and artificial caves in a few million years at most as they are compressed by the weight of the rocks above them ("tunnel squeezing").
      - throw310822 3mo ago
        How long to dissolve carved stone sculptures (in sizes ranging from 1cm to 100m?) And how long does it take to dissolve skin? Footprints? Because we have those from hundreds of millions of years ago.
        T-A 3mo ago
        > How long to dissolve carved stone sculptures (in sizes ranging from 1cm to 100m?) A quick search on "rock weathering depth per century" suggests a "typical range" of 0.05 mm to 6 mm, depending on rock type and environmental factors. At 0.05 mm, a stone object with radius 0.5 cm would crumble in 10000 years. With radius 50 m, it would take 100 million years. I would expect them to be unrecognizable long before that though. > And how long does it take to dissolve skin? Footprints? Because we have those from hundreds of millions of years ago. What do those findings tell you about the cognitive abilities and social organization of the creatures who left them behind?
        throw310822 3mo ago
        > A quick search on "rock weathering depth per century" That's a great illustration of what I meant. Of course an exposed rock consumes away in the space of a few millennia- this is exactly where the "Silurian theory" comes from. Yet it's also obvious that we have plenty of perfectly conserved rocks that are intact after hundreds of millions of years- i.e. fossils. Any small sculpture buried in clay can survive for an eternity. > What do those findings tell you about the cognitive abilities and social organization Skin? Like, with clothes on, or the shape of clothes? And shoes and hiking gear? Footprints with the shape of boots? Drawings "I LOVE YOU" in the sand? The shape of a coca-cola bottle buried in solidified clay? Come on...
  - nwah1 3mo ago
    Yea, but if humans went extinct tomorrow, very little human artifacts would remain after millions of years. Indeed, most would be gone well before that. How much stuff from the 18th century still remains, in percentage terms?
    - nkrisc 3mo ago
      Very few things would in fact remain, you’re correct. But we’ve also created radioactive elements with half lives of many millions of years. While there would probably very little direct evidence of humans after millions of years, there would probably be at least some anomalous evidence someone could find.
    - bensyverson 3mo ago
      Unless it was burned, melted, decomposed or crushed to dust, it's all out there or in a landfill somewhere. I do find it difficult to believe that we would not leave enough fossil and mineral evidence for future paleontologists to find. I get that the surface will churn, but layers of rock routinely become exposed, revealing the geological history of the area. No tea cup shards, no impressions of rusted cars in the mud, no concentration of metal in strangely rectilinear formations that suggests skyscrapers?
    - neaden 3mo ago
      There would still be many signs. Dug up mines, metal alloys that don't exist in nature along with refined metals in quantities they don't exist, animal and plant species we bred along with all the ones we made extinct.
- fnord77 3mo ago
  > And someone is saying there could have been an entire advanced civilization 400 million years ago, large and powerful enough to cause climate change, and that no traces of it would possibly be left? If humanity vanished today, in 1 million years almost all of our artifacts would be gone or burned under miles of subduction. In 10 million years there would literally be nothing left.
  - kergonath 3mo ago
    > If humanity vanished today, in 1 million years almost all of our artifacts would be gone or burned under miles of subduction. That is completely incorrect. We have sedimentary rocks from 100 M years ago on the Earth’s surface right now, that never underwent any kind of subduction.
  - DFHippie 3mo ago
    > under miles of subduction Subduction only occurs at plate boundaries and is not nearly this fast. Continental plates float on top like foam and do not get subducted. It's the oceanic plate that is created at mid-ocean ridges and gets subducted at the margins.
  - throw1234567891 3mo ago
    Bollocks. We find fossils millions of years old right on the surface.
- randomImmigrant 3mo ago
  Actually correct. We have very very few fossils compared to the millions of species that have evolved and gone extinct over 4 billion years. The fossils we do have are of highly successful species in that geography. It’s a matter of chance, leaving behind a fossil, after all. And unlike biological matter that can fossilize, industrial structures etc do not. All our manufactured stuff has very short life once it reaches the crust and starts getting compacted. The more time you add, the better the odds we’d find this evidence lost. And if this wasn’t a global, but more localized pre-human civilization, the evidence would be thinner still. Which is why this isn’t a scientific hypothesis really. It’s more showing you the limits of scientific inquiry into the deep history of Earth.
  - throw310822 3mo ago
    > It’s more showing you the limits of scientific inquiry into the deep history of Earth. I think this is it: the point of this argument is to inspire some awe in the listener, making them realise how vast Earth's time is compared to our horizons. But in practice, the argument is wrong. A dead animal's skin is expected to lasts weeks to months- and yet we have fossilised specimens. A footprint typically lasts hours, and yet we have ones that are hundreds of millions of years old. Even if the expected lifespan of our artifacts is nothing in comparison with these timespans, a small percentage of artifacts will either be preserved or leave recognisable traces- exactly as it happened for soft tissues and footprints. It's extremely naive to think that none of this will leave traces.
    - randomImmigrant 3mo ago
      No the argument isn’t wrong. It isn’t proof of a particular civilization, but it’s not wrong about the detection threshold for such things. You can’t compare fossilization, which is very dependent on certain properties of biological tissue, and extrapolate from that to all matter.
xg15 3mo ago
> or it could’ve been the eruption of a monster volcano, the sort that presently smolders beneath the Atlantic. I know about Yellowstone, Campi Flegrei, etc, but I haven't heard about a supervolcano below the Atlantic. What's that referring to?
- MrDrMcCoy 3mo ago
  There's a seam of volcanic mountains that runs down the center of the Atlantic, but nothing that resembles a supervolcano. The supervolcano complex under the Pacific is one of the largest known in the solar system, however.
  - xg15 3mo ago
    > There's a seam of volcanic mountains that runs down the center of the Atlantic Yeah, that's the pacific rim, which in some sense is the opposite of a volcano.
    - masklinn 3mo ago
      No the seam at the center of the Atlantic is a mid-oceanic ridge, and it’s very much like a volcano since magma comes out. Icelandic volcanology comes from it being on the ridge. There are ridges off of the US coast (Explorer, Juan de Fuca, Gorda) but the ring of fire which surrounds the pacific is mostly subduction areas.
      - xg15 3mo ago
        Sorry, you're right of course (and yeah, the Pacific rim can obviously not be in the Atlantic, typed too fast there...) With "opposite" I meant the role in plate tectonics, in that classical volcanoes seem to mostly appear near subduction zones or hotspot but not on the ridges from what I know. (Iceland being the exception, but even there it's because of a hotspot that happens to be located right on the ridge) But I think the ridge system usually does not have volcanoes in the sense that there are magma chambers that fill up or cause eruptions. So the usual scenario of the "asleep supervolcano" does not apply. > The supervolcano complex under the Pacific is one of the largest known in the solar system, however. That sounds interesting. Do you have some links about that?
steve1977 3mo ago
The timelines don't really add up for me. So there could have been this hypothetical civilization 55 million years ago already. And they've only just disappeared (if they did) 10'000 or so years ago? Without a trace? Also, no, a conspiracy cannot be the answer to a question we've not yet asked. The word has a clear meaning, it requires people to conspire to hide something from you.
- randomImmigrant 3mo ago
  No. The idea is they could have lived and thrived for a few thousand years a few million years ago, then gone extinct.
  - steve1977 3mo ago
    That's not what the articles says though: "Ancient mystical texts hint at earlier creation, the life that preceded the Garden, prequels to Genesis. These incarnations are not reported in the Bible because they are none of your goddamn business, but the evidence is everywhere. Some students of conspiracy believe there was a time when lizard people shared the earth with modern men, the older race dying as the younger emerged from the forest. The last of the lizards were worshipped as gods; these were the deities of ancient India and Greece. The technology—weapons and machines—created miracles. You can see the lizard kings in carvings from Mesopotamia, the oldest historical records, where humans bow before reptile men. You find them again in the Torah, where they appear as Nephilim..."
    - randomImmigrant 3mo ago
      That’s not the Silurian hypothesis the astrophysicists put out. That’s the author extending it to fit those myths.
      - xg15 3mo ago
        Yeah, the author is contradicting himself here: On the one hand, that civilization must have ended several million years ago, so erosion and plate tectonics had time to erase all traces - but on the other hand, humans were still having lively exchanges with those guys and viewing them as a normal part of their world in 10.000 BC...
Qem 3mo ago
Reminds me of this comic: https://badspacecomics.com/scour-copy-copy https://badspacecomics.com/scour-copy-copy
api 3mo ago
This is a good thought experiment to show how time is as vast as space. 400 million years ago is as distant as the stars. The Earth was a different planet then, in a sense. It’s also yet another Fermi paradox answer. Even if our civilization lasts for millions of years, that’s a blip. We are searching both space and time and both are incomprehensibly vast.
- Razengan 3mo ago
  > time is as vast as space. This is what I always say to "Why haven't we found any aliens yet??" Hell, we wouldn't even have known about the existence dinosaurs, lifeforms on THIS VERY PLANET, if we hadn't chanced upon their remains.
  - api 3mo ago
    I’d also say that we do not know for certain that no dinosaurs, such as raptors perhaps, were intelligent enough for language and culture. At that age we can be pretty sure they did not have industry but they could have been like tribal hunter gatherers. If they did not build a lot and at large scale we’d have basically zero chance of finding anything. Stone, wood, animal skins, pottery, arrow heads, tools, etc., all that would be long gone. Metal would too but it might leave diagnostic traces, as would synthetic chemistry (plastics) or large scale fuel use. Birds, the modern still living closest relatives of dinosaurs, are often strikingly intelligent especially relative to their brain mass. Dinosaurs had small brains relative to body size but while there is a correlation there with intelligence it’s not perfect. There’s exceptions, animals with small relative brain sizes that seem very smart, like elephants.
- hdgvhicv 3mo ago
  How can a galaxy spanning civilisation fail. If life can spread to other worlds, unless you get FTL, how could you end all life in a galaxy As such it seems impossible for life to have reached interstellar travel anywhere in the Milky Way before at most a few million years ago, otherwise we would see it. Which is weird because life surely can’t be that rare in the entirety of space time. Of course the galaxy could be teaming with non interstellar life, but once you reach mankind’s level of sentience and technology it dormant seem a massive jump to interstellar, and once that happens there’s no way to put the genie back in the bottle.
jmclnx 3mo ago
>The oldest place on the earth’s surface—a stretch of Israel’s Negev Desert I do not understand this statement, I thought an area in Quebec was around 3 - 4 billion years old. I looked, seems Australia may have the oldest area: https://www.bbc.com/travel/article/20220126-is-the-pilbara-the-oldest-place-on-earth https://www.bbc.com/travel/article/20220126-is-the-pilbara-t... But I say the article could be true, but the only issue I have is the large dinos. I would think they could be an impediment to any organized settlements. One other thing, didn't most of our fossil fuels come from the Carboniferous era ? https://en.wikipedia.org/wiki/Carboniferous https://en.wikipedia.org/wiki/Carboniferous
- delichon 3mo ago
  The claim isn't about the age of rock, but that the surface has churned almost everywhere. Israel does contain the oldest measured continuous surface at about 1.8M yo, but nobody claims to have looked everywhere.
  - DFHippie 3mo ago
    How churned is "churned"? Does this mean particular pebbles have have been found to have lain in their current arrangement for 1.8 million years, or just that not much has happened? I expect any arid region far from the poles or mountains and lacking dune fields will have similar patches of inert land. Much of Australia would fit this bill.
meindnoch 3mo ago
Joe Rogan tier pseudoscience.
markus_zhang 3mo ago
However, since we do have plenty of fossils from Silurian, it is hard to believe that none of the advanced technologies never left any hint. Any idea?
- jerf 3mo ago
  Yes. We'd find mines, where the richest veins were mined out and what's left is spread in a pattern that clearly appears to be "a rich deposit but with the best stuff taken already". The mine itself would have long collapsed but would also leave interesting evidence, a pattern of mismatched geological layers that rather than looking like an earthquake or a tectonic upheaval would be something that is relatively clearly shaft-shaped and if followed into the mountain would open out into a pattern that indicates intelligent mining activity as the anomaly is further charted. Places where there is suddenly a vast collection of foreign rocks from the other side of the world that can't be explained by glaciers. Radioactivity from nuclear tests that can't be explained by stellar phenomena and leave a layer of weird isotopes and isotope ratios all around the world, as we already have done. And while we aren't to the point we'd have found this quite yet necessarily, evidence on the Moon where unlike Earth evidence probably would in fact persist for millions of years, especially if it ever attained any scale, e.g., "a large complex of cities" might still leave a visible mark on the surface easily visible to modern satellites and clearly with no other explanation available as to what caused it. People get stuck on the idea that the only way to determine there was intelligent life earlier is to find a super complicated artifact which obviously can't survive, but there are footprints we've left in the world that are way, way larger than a cell phone or even a major city. I don't find it hard to believe we've lost entire human civilizations. In fact I'd call it the smart bet. Maybe those civilizations were even a bit more sophisticated than we'd have thought, with maybe an earlier and entirely unknown Iron Age popping up somewhere for some period of time or something. But this is the first major technological civilization this planet has ever seen, even across geological time scales. And those lost human civilizations never reached to the level where they took all the easy resources like we have, because if they had, we wouldn't be able to get them. Some resources we call "non-renewable" do replenish on a few million year time scale, but we also pull lots of resources out of billion-year-old rocks, such as copper mines in northern Michigan which are pulling resources out of pre-Cambrian rocks. Clearly nobody else has been there, at scale.
zabzonk 3mo ago
Dr Who and the Silurians had this covered: https://tardis.fandom.com/wiki/Silurian https://tardis.fandom.com/wiki/Silurian
- atombender 3mo ago
  That is explicitly referenced in the article.
hliyan 3mo ago
I don't think we have to go that far back. Plate tectonics, submersion and weathering does a good enough job of wiping the slate clean off the surface of the Earth, that any evidence of earlier hominids developing pre-industrial, coastal civilizations say, a million years ago, would be now under the crust. What we consider civilization is about 5000 years old, so it's not inconceivable that the cycle might have occurred multiple times during geologic time spans. Perhaps this is the first time civilization was not interrupted and made its way through to a technological civilization.
- neaden 3mo ago
  I mean sure, if they somehow didn't have any trade goods that went in land, didn't work with metals enough to do any appreciable mining, and didn't breed any plants or animals enough to change their genetics. Any hypothetical hidden past civilization would have to have been weird in a number of ways to not leave any evidence.
- colechristensen 3mo ago
  Huh? We have plenty of fossil evidence from, from your example, a million year old hominids. Far more than we would need to expect to see evidence of civilization. Subduction makes up for a tiny tiny proportion of where coastal land "goes" in any age. You'd need an enormous set of coincidences for a past civilization of hominids to go unnoticed.
- engineer_22 3mo ago
  >coastal civilizations say, a million years ago, would be now under the crust. Nah, you way off on that, coastlines have remained relatively same last million years, def not subducted into an ocean trench
- mda 3mo ago
  Are you sure? what about fossils and other remains? So far there is zero evidence that there was an advanced or non advanced civilization. Unfortunately this nonsense is the bread and butter ot pseudo archeologists.
amazingamazing 3mo ago
if all dolphins were wiped out could we know that they were ever here from physical evidence?
- nkrisc 3mo ago
  We’ll never know of the existence of most species that ever existed. Fossilization is rare.
  - amazingamazing 3mo ago
    right, so how can one easily say this hypothesis is false? "advanced civilization" seems to be strangely characterized. would something a few steps above beavers be advanced enough?
    - vjvjvjvjghv 3mo ago
      How can anyone say the hypothesis is true? There is absolutely no evidence for it. It’s just a thought experiment.
    - krapp 3mo ago
      When people speculate about "advanced" ancient civilizations they usually mean said civilizations had technology at least as advanced as our own if not more so like nuclear weapons, antigravity, modern manufacturing and engineering, etc. A hypothesis that millions of years ago humans or some progenitor could build rough shelters out of sticks isn't particularly interesting.
      - nkrisc 3mo ago
        You don’t have to even hypothesize about other species that can create shelters out of sticks, they exist today.
    - nkrisc 3mo ago
      Typically the ones proposing a hypothesis have the burden of proof. Still waiting on any evidence in favor of the hypothesis. I won’t hold my breath.
dash2 3mo ago
I can't speak to dinosaur people, but the population genetics of our own DNA reveals that there were never many humans on the planet till recently, so that rules out any very large human civilization. (Unless they genetically altered themselves to hide the evidence! Ahaaa...)
- graemep 3mo ago
  If whole populations were wiped out and the world was repopulated by a small remnant would that not account for it? Or if an extinct human species had an advanced civilisation?
  - throw1234567891 3mo ago
    No. That’s exactly how we know.
  - AlotOfReading 3mo ago
    The founder effect differs between small populations filtered from a large population vs a smaller parent population. I want to point out that the silurian hypothesis is specifically about civilizations removed from us by geologic time. Advanced human precursor civilizations are much more effectively ruled out by the current evidence. Basically, a hypothetical precursor society either has to look very different from any we know about and materialize out of nowhere like alien colonists, or they didn't exist. For example, we know they weren't using large amounts of fire because nothing in the global charcoal records points to that. We know they weren't using plants that produce pollen because we don't find phytoliths with domestication indicators. We know they weren't using surface metals, because there was lots of that still around when the classically ancient civilizations started. We know they didn't contribute significantly to the gene pool. We have no material culture from them. We don't have a location on Earth they would have lived in. Etc.
    - deleted 3mo ago
      [deleted]
    - simonh 3mo ago
senshan 3mo ago
Isaac Asimov's Nightfall [0], but on a longer cycle? Jokes aside, what is the evidence, beyond "Ancient mystical texts"? [0] http://www.myths.com/pub/fiction/science-fiction/Asimov/Nightfall-and-Other-Stories.pdf http://www.myths.com/pub/fiction/science-fiction/Asimov/Nigh...
- graemep 3mo ago
  I think there is no evidence for it, but I think the point of the Silurain hypothesis (which the article does not convey well) is that if there were such civilisations we would not know as its unlikely we would find any evidence.
  - senshan 3mo ago
    So it not a falsifiable statement from the onset? https://en.wikipedia.org/wiki/Falsifiability https://en.wikipedia.org/wiki/Falsifiability
    - vjvjvjvjghv 3mo ago
      I don’t think it’s necessary to falsify a statement that has absolutely no evidence for it being true.
    - jknoepfler 3mo ago
      It is falsifiable, in the sense that we have ample evidence of the many forms of life that have existed on earth... including fossil evidence, genetic evidence, preserved tissue samples and a long litany of other pieces of data broadly consilient with our understanding the biological timeline. On the other hand, we have zero evidence of Silurians or whatever. Those two observations are inconsistent and require explanation. Sure, one can hedge and qualify and excuse or whatever, and on pain of irrationality we have to allow that it's possible we're missing evidence of one of a bajillion possible competing hypotheses about intelligent life... but the theory most consistent with the evidence we have is that there wasn't any. That's falsifiable enough for me? The criterion of falsifiability pushed by positivists is kind of crappy anyway, it doesn't speak well to how we build models of the world while doing actual empirical work (and is itself non-falsifiable), but in practical terms idk, I don't see much to recommend the Silurian Hypothesis over the null hypothesis, so to speak.
Razengan 3mo ago
Petroleum could be the byproduct of a previous civilization. Also, just as we "engineered" animals and plants through selective breeding, previous animals/plants could have been the results of selective breeding by a previous civilization: There'd be no way to tell just as there'd be no way to tell our "tampering" a few million years in the future.
- kergonath 3mo ago
  > Petroleum could be the byproduct of a previous civilization. How so? We know how it forms, there is no real gap in understanding there. What could lead to the kind of distribution of oil and gas fields we can observe?
  - Razengan 3mo ago
    Just fun to think about and base fiction on I mean, would an ant walking on a highway be able to tell that it's artificial?
    - kergonath 3mo ago
      Probably not, but an ant cannot do any kind of isotope analysis.
      - Razengan 3mo ago
        hah but again, would someone a million in the future be able to tell that today's bananas, corn, watermelons, cattle, dogs etc. were the result of selective breeding by an intelligent species? (with no human records for reference)
        antisthenes 3mo ago
        > would someone a million in the future be able to tell that today's bananas, corn, watermelons, cattle, dogs etc. were the result of selective breeding by an intelligent species? They might be able to, based on when these disappeared, by comparing them to something more durable that is easier to date definitevely. All those organic things bred to fulfill the purpose of being useful to our civilization would very quickly disappear and become outcompeted by the undomesticated species. This sudden disappearance (along with the disappearance of more durable artefacts, like steel/plastics) might hint to someone that these species "are not like the others". Also by tying them to the cutoff in human remains (this is assuming humans disappear along with advanced civilization)
rdiddly 3mo ago
Interesting topic, but (to immediately veer off of it) I really wish he would find another word and stop misusing "conspiracy." The word has already been through hell.
- ptx 3mo ago
  That was my first reaction as well. The author seems very confused about it. He starts off defining it as something that is unknown or secret, and more specifically, he goes on to say, a secret "kept by a nefarious elite". I suppose secrets are usually associated with conspiracies, but a secret is not a conspiracy and conspirators don't have to be an elite. And then he says that in this case, it's the Earth itself that's conspiring alone. This contradicts all the dictionaries I consulted, which define it to involve multiple parties, which makes sense considering the etymology.
Robotbeat 3mo ago
Technical ceramics would have survived.
gradus_ad 3mo ago
I have a toy hypothesis that once civilization level intelligent life emerges it never disappears barring the planet it inhabits being vaporized by some unfortunately directed GRB or some similar catastrophe. Our knowledge is becoming holographic such that to prevent the reemergence of civilization one would have to wipe out all of us at once.
- snapplebobapple 3mo ago
  depends how you define civilization level life.if you mean we cant be bumped back to hunter gatherers without wiping out almost all of us, you are probably correct. If you mean we will always have computers and the ability to split the atom, i dont agree. Knowledge and industry is way more fragile and we have loat working knowledge of simpler processes in favor of more advanced ones so it wont be that easy rebuilding through the lower rungs of the tech tree.
aghilmort 3mo ago
Time Machine movie reboot did this in opposite direction into future decently well dude wind hundreds of thousands of years into future, sands of time, etc. modulo two warring biological descendants of humans not full diff species tho
tonymillion 3mo ago
The fact there is still coal(and oil) in the ground pretty much rules out any "advanced" industrialized civilization that came before us. I also use the Carboniferous Period as a metric as to why "Advanced alien life" isn't more abundant (and I believe it should be factored into the Fermi equation)... All those trees growing, soaking up sun, dying and just laying there to be compressed and buried without anything to decompose them, and then humans using them like solar batteries to power civilization (i.e. burning the coal), is one of those million-to-one things that enabled the human race to develop beyond basic society. We needed all that coal and oil (and gas) based power to get to the point - industrially and technologically - where we could even build solar panels or nuclear to replace them, so its not like you could start from first principals and jump straight to modern power generation either. The odds that the same sequence of events - fungus and bacteria not having the tools to decompose lignin (or whatever the alien equivalent is) - to happen on an extra-solar planet is ... pardon my pun ... astronomical :D (yes, I used a dash to separate ideas in a sentence, deal with it...)
- inhumantsar 3mo ago
  one thing I enjoyed about The Children of Time by Adrian Tchaikovsky: the spiders learned to build "computers" out of ant colonies by hijacking the ants ability to generate and respond to chemical stimuli. not that it makes me believe in the silurian hypothesis, but i'm always reminded of that whenever i start to think "well it couldn't possibly be done any other way".
dav_Oz 3mo ago
This article is a weird mash-up of an actually very interesting paper [0] with random personal slop like i've asked my rabbi, consulted my kabbalah-initiated friends and for the fun mixed it up with some fashionable ancient text (Mahabharatha) So maybe just stick right to the paper itself and its clearly stated motivation? > Perhaps unusually, the authors of this paper are not convinced of the correctness of their proposed hypothesis. Were it to be true it would have profound implications and not just for astrobiology. However, most readers do not need to be told that it is always a bad idea to decide on the truth or falsity of an idea based on the consequences of it being true. While we strongly doubt that any previous industrial civilization existed before our own, asking the question in a formal way that articulates explicitly what evidence for such a civilization might look like raises its own useful questions related both to astrobiology and to Anthropocene studies. Thus, we hope that this paper will serve as motivation to improve the constraints on the hypothesis so that in future we may be better placed to answer our title question. [0]https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/silurian-hypothesis-would-it-be-possible-to-detect-an-industrial-civilization-in-the-geological-record/77818514AA6907750B8F4339F7C70EC6 https://www.cambridge.org/core/journals/international-journa...
ma2kx 3mo ago
I think the article greatly underestimates our archaeological capabilities. We can identify five mass extinctions in the last 500 million years, so why should such a civilization simply be overlooked? Of course, we wouldn't find abandoned ruins, but the idea that an industrial civilization wouldn't leave behind any detectable artifacts is practically impossible. Perhaps there were a few primate species before that could make fire and hunt with bows and arrows, but certainly nothing industrial and hardly any extensive agricultural culture.
- RunSet 3mo ago
  > I think the article greatly underestimates our archaeological capabilities. "they found a single forerunner to their idea of deep time. It came not from science, but from science fiction. At this level of conjecture, there’s little difference. It was an episode of Dr. Who" also betrays an ignorance of the trope originator.[0] [0] https://en.wikipedia.org/wiki/Serpent_Men https://en.wikipedia.org/wiki/Serpent_Men
jake_and_fatman 3mo ago
I'm butt hurt that I'm five paragraphs in and still have no idea what the hypothesis is.
GolfPopper 3mo ago
From author and druid John Michael Greer's essay, "The Next Ten Billion Years"[1], "One hundred million years from now: The universe has a surprise in store for the corvins, though. Their first moon landing included among its goals the investigation of some odd surface features, too small to be seen clearly by Earth-based equipment. That first lander thus set down on a flat lunar plain that, a very long time ago, was called the Sea of Tranquillity, and so it was that the stunned corvin astronauts found themselves facing the unmistakable remains of a spacecraft that arrived on the moon in the unimaginably distant past. A few equivocal traces buried in terrestrial sediments had suggested already to corvin loremasters that another intelligent species might have lived on the Earth before them, though the theory was dismissed by most as wild speculation. The scattered remnants on the Moon confirmed them, and made it hard for even the most optimistic corvins to embrace the notion that some providence guaranteed the survival of intelligent species. The curious markings on some of the remains, which some loremasters suggested might be a mode of visual communication, resisted all attempts at decipherment, and very little was ever learnt for certain about the enigmatic ancient species that left its mark on the Moon." 1. https://www.resilience.org/stories/2013-09-05/the-next-ten-billion-years/ https://www.resilience.org/stories/2013-09-05/the-next-ten-b...
- xg15 3mo ago
  What an amazing read! (and only slightly depressing) Though I'm kind of disappointed the last section did not end with fusion power, stellar migration and artificial intelligence...
- gtowey 3mo ago
  Funny, as I was reading the original article, I was thinking that anything left on the moon would survive being recycled by plate tectonics. It seems like reaching the moon isn't such a stretch for any technological civilization, so the lack of preexisting artifacts counts as pretty definitive for me.
  - saidnooneever 3mo ago
    point at a spot on the moon which was not hit by an object, its not easy. very big things have hit it too. additionally radiation is much more so decay is accelerated a lot? (might be wrong but i think so?)
netbioserror 3mo ago
To recognize the possibility, one has to grapple with incredible scale and deep time: In roughly 300 million years (1/10th of the time life has been around), the Appalachians split off from the Atlas; the Atlantic Ocean first started splitting open; uplifts underneath North America pushing the West up from the seabed and caused the rivers to carve millions of acres of sandstone landscape down, leaving towering plateaus, cliffs, and eventually river chasms. Over the 3 billion years before that, what was carried away like so much sediment? What was subsumed by subduction boundaries? On a much more recent timescale, one of the dominant theories of the emergence of civilization places the ancestors of the Sumerians in a stupendously fertile valley at the bottom of what is now the Persian Gulf, eventually flooded during the retreat of the glacial maximum and covered in Tigris & Euphrates sediment. It could be the very origin of regional flood and primordial garden myths. But it's all buried.
davidbjaffe 3mo ago
Silurian Hypothesis, SETI, a widely help motivation for space exploration, much of sci-fi: all posit a high-ish rate of life (or intelligent life) invention, because the alternative is terrifying. I/we need/enjoy this, but it's fiction. When humans reason about the rate, they're extremely biased by what they want to be true.
- ohthehugemanate 3mo ago
  +1 in general that anthropic bias is strong, but it cuts both ways, even in relatively hard nosed statistical models (@see Drake equation vs Rare Earth hypothesis). Truth is, there are a ton of factors we just can't observe (yet?) that play a big part. For example, since the rare earth hypothesis was published, we know a lot more about exoplanets, and earth-range size in the habitable zone of a stable star and galaxy appears much more common than we thought. But we don't know if plate tectonics are really required, or gas giant "vacuum cleaner" planets int he same system, or even oxygen. But we do know that the minimum value for intelligent species is at least 1, because we exist. For me, it's carl sagan's "invisible dragon" comparison that sticks in the back of my head. If there's intelligent life out there (or in earth's ancient past) but there's no physical way to detect or know it... Then like the invisible dragon in mu garage, it's the same as not existing. Maybe we'll develop new techniques and gather new evidence, but until we figure out how to bend spacetime for FTL anything, or find clear evidence, we should act as if it isn't/wasn't there. So TFA says that 55M years ago there was a climate fluctuation that looks similar to the anthropocene one. Good start. But interpretation of ancient stories across cultures is practically the definition of anthropic bias. We have to wait until there is real evidence that the temperatuee bump was dragonfire and not my heating system acting up, to ascribe cause.
SilentM68 3mo ago
I really enjoyed this article. It was a very pleasant read. The author should write a book and or movie script. The original Doctor Who Silurian episodes were fun to watch. Makes sense to connect dinosaurs or the remnants of Silurian civilization to dragons and deities. Star Trek Strange New Worlds S04E01 deals with the dinosaurs and Mars @ 65 million years ago. The story is rather intriguing and fun to watch as well. Invincible S04E04 deals with the various ages that planet Earth has gone through and has a different take on the meaning of Hell and Satan and why they exist. Last episode of the Season 4 is rather interesting, as well as it relates to the possible next phase or not, of human evolution.
mcswell 3mo ago
I wrote a sci-fi short story on this idea once. It took place in the present, and left the truth of the hypothesis open. Submitted it to Analog, but it was rejected. I suppose there are now places one can self-publish sci-fi stuff, but I'm not sure I can even find my original. Edit: Did a Linux find, and...it did find the story. Unfortunately, it didn't find me a place to publish it.
gorgolo 3mo ago
Surprised so few are pushing back against some of the claims in this article. Eg that the entire surface of the earth gets replaced in a million years by tectonics. Many of the large plates are more than 1000km across, they’d need to be moving meters per year for that to happen. In reality it’s cm per year. Also typically it’s oceanic plates that get subducted and take material under the crust, not continental plates. If it were true, then how do we see dinosaur fossils, and creatures even older than that; how do we find rocks that are over a billion years old. This doesnt reject the possibility that there was a civilization tens of millions of years ago, but it makes the article hard to take seriously. If you’re gonna spend time writing an article on this you might as well try to research it a bit more. Someone is gonna read this and repeat this nonsense like it’s some fun trivia.
- JPLeRouzic 3mo ago
  > Many of the large plates are more than 1000km across, they’d need to be moving meters per year for that to happen. In reality it’s cm per year. A plate moving one centimeter per year would move over 10,000 km (6000 miles) over a million year, isn't? It's two times the distance from New-York to San Francisco, one fourth of the Earth circumference! And the Cretaceous–Paleogene extinction event was approximately 66 mya.
  - ben_w 3mo ago
    > A plate moving one centimeter per year would move over 10,000 km (6000 miles) over a million year, isn't? No, 10,000 km is 10e6 meters, or 1e9 cm, so at 1cm/year it would take a billion years, not a million.

75 points by andsoitis 3mo ago

So we have microbial fossils from 3.5 billion years ago, fossilised 300 million year old skin, bones from almost 200 my ago, even actually soft tissue inside a fossilised bone from 70 my ago. Ah, footprints too, the most unsubstantial matter of all: pure shape. That's in addition to all the million other fossils that are so common we hardly care: shells, small bones, etc. And someone is saying there could have been an entire advanced civilization 400 million years ago, large and powerful enough to cause climate change, and that no traces of it would possibly be left? Like, billions of individuals, cities, factories, metals, concrete, mines, wells, roads and bridges and tunnels, stone sculptures!, plastic, waste dumps, farms, agricultural land, billions and billions of artifacts of all materials, most of them entirely artificial. All gone because "nothing resists 400 my" and, "oh btw, check this dinosaur footprint and this fossilised piece of skin, how cool"?

gorgoiler 3mo ago
The counter argument: dinosaurs were around for a staggering amount of time, no pun intended. 165 million years is reasonably long enough to ensure they left behind some nests, bones, and a feather or two. Modern humans have been around for more like 0.02 million years. The counter-counter argument is that while we’ve been here for a comparative blink of an eye, we’ve left behind 4 orders of magnitude more stuff than just nests, bones, and a feather or two.
- throw310822 3mo ago
  Indeed. Did a rapid check on T-rex, just as an example. Was around for max 3.6 million years. Max population at any one time must have been around 20k individuals. We have about 150 skeletons. So current human population is 400 thousand times the maximum T-rex population at any one time. A few decades are enough to produce more human individuals than the entire T-rexes history. We also have the ability to go (and die) pretty much anywhere, so there will be human skeletons in every crevice, depth and environment on Earth. We also produce an absolutely staggering amount of artifacts of all kinds, from plastic straws to giant tunnels and artificial caves. There are zero chances an advanced civilisation on Earth won't be aware of us in 400 million years.
  - T-A 3mo ago
    >We also produce an absolutely staggering amount of artifacts of all kinds, from plastic straws to giant tunnels and artificial caves. Plastic will be gone in ~1000 years, https://www.activesustainability.com/environment/waste-planet-digest-how-long-it-takes-to-decay https://www.activesustainability.com/environment/waste-plane... tunnels and artificial caves in a few million years at most as they are compressed by the weight of the rocks above them ("tunnel squeezing").
    - throw310822 3mo ago
      How long to dissolve carved stone sculptures (in sizes ranging from 1cm to 100m?) And how long does it take to dissolve skin? Footprints? Because we have those from hundreds of millions of years ago.
      - T-A 3mo ago
        > How long to dissolve carved stone sculptures (in sizes ranging from 1cm to 100m?) A quick search on "rock weathering depth per century" suggests a "typical range" of 0.05 mm to 6 mm, depending on rock type and environmental factors. At 0.05 mm, a stone object with radius 0.5 cm would crumble in 10000 years. With radius 50 m, it would take 100 million years. I would expect them to be unrecognizable long before that though. > And how long does it take to dissolve skin? Footprints? Because we have those from hundreds of millions of years ago. What do those findings tell you about the cognitive abilities and social organization of the creatures who left them behind?
        throw310822 3mo ago
        > A quick search on "rock weathering depth per century" That's a great illustration of what I meant. Of course an exposed rock consumes away in the space of a few millennia- this is exactly where the "Silurian theory" comes from. Yet it's also obvious that we have plenty of perfectly conserved rocks that are intact after hundreds of millions of years- i.e. fossils. Any small sculpture buried in clay can survive for an eternity. > What do those findings tell you about the cognitive abilities and social organization Skin? Like, with clothes on, or the shape of clothes? And shoes and hiking gear? Footprints with the shape of boots? Drawings "I LOVE YOU" in the sand? The shape of a coca-cola bottle buried in solidified clay? Come on...
- nwah1 3mo ago
  Yea, but if humans went extinct tomorrow, very little human artifacts would remain after millions of years. Indeed, most would be gone well before that. How much stuff from the 18th century still remains, in percentage terms?
  - nkrisc 3mo ago
    Very few things would in fact remain, you’re correct. But we’ve also created radioactive elements with half lives of many millions of years. While there would probably very little direct evidence of humans after millions of years, there would probably be at least some anomalous evidence someone could find.
  - bensyverson 3mo ago
    Unless it was burned, melted, decomposed or crushed to dust, it's all out there or in a landfill somewhere. I do find it difficult to believe that we would not leave enough fossil and mineral evidence for future paleontologists to find. I get that the surface will churn, but layers of rock routinely become exposed, revealing the geological history of the area. No tea cup shards, no impressions of rusted cars in the mud, no concentration of metal in strangely rectilinear formations that suggests skyscrapers?
  - neaden 3mo ago
    There would still be many signs. Dug up mines, metal alloys that don't exist in nature along with refined metals in quantities they don't exist, animal and plant species we bred along with all the ones we made extinct.
fnord77 3mo ago
> And someone is saying there could have been an entire advanced civilization 400 million years ago, large and powerful enough to cause climate change, and that no traces of it would possibly be left? If humanity vanished today, in 1 million years almost all of our artifacts would be gone or burned under miles of subduction. In 10 million years there would literally be nothing left.
- kergonath 3mo ago
  > If humanity vanished today, in 1 million years almost all of our artifacts would be gone or burned under miles of subduction. That is completely incorrect. We have sedimentary rocks from 100 M years ago on the Earth’s surface right now, that never underwent any kind of subduction.
- DFHippie 3mo ago
  > under miles of subduction Subduction only occurs at plate boundaries and is not nearly this fast. Continental plates float on top like foam and do not get subducted. It's the oceanic plate that is created at mid-ocean ridges and gets subducted at the margins.
- throw1234567891 3mo ago
  Bollocks. We find fossils millions of years old right on the surface.
randomImmigrant 3mo ago
Actually correct. We have very very few fossils compared to the millions of species that have evolved and gone extinct over 4 billion years. The fossils we do have are of highly successful species in that geography. It’s a matter of chance, leaving behind a fossil, after all. And unlike biological matter that can fossilize, industrial structures etc do not. All our manufactured stuff has very short life once it reaches the crust and starts getting compacted. The more time you add, the better the odds we’d find this evidence lost. And if this wasn’t a global, but more localized pre-human civilization, the evidence would be thinner still. Which is why this isn’t a scientific hypothesis really. It’s more showing you the limits of scientific inquiry into the deep history of Earth.
- throw310822 3mo ago
  > It’s more showing you the limits of scientific inquiry into the deep history of Earth. I think this is it: the point of this argument is to inspire some awe in the listener, making them realise how vast Earth's time is compared to our horizons. But in practice, the argument is wrong. A dead animal's skin is expected to lasts weeks to months- and yet we have fossilised specimens. A footprint typically lasts hours, and yet we have ones that are hundreds of millions of years old. Even if the expected lifespan of our artifacts is nothing in comparison with these timespans, a small percentage of artifacts will either be preserved or leave recognisable traces- exactly as it happened for soft tissues and footprints. It's extremely naive to think that none of this will leave traces.
  - randomImmigrant 3mo ago
    No the argument isn’t wrong. It isn’t proof of a particular civilization, but it’s not wrong about the detection threshold for such things. You can’t compare fossilization, which is very dependent on certain properties of biological tissue, and extrapolate from that to all matter.

xg15 3mo ago

> or it could’ve been the eruption of a monster volcano, the sort that presently smolders beneath the Atlantic. I know about Yellowstone, Campi Flegrei, etc, but I haven't heard about a supervolcano below the Atlantic. What's that referring to?

MrDrMcCoy 3mo ago
There's a seam of volcanic mountains that runs down the center of the Atlantic, but nothing that resembles a supervolcano. The supervolcano complex under the Pacific is one of the largest known in the solar system, however.
- xg15 3mo ago
  > There's a seam of volcanic mountains that runs down the center of the Atlantic Yeah, that's the pacific rim, which in some sense is the opposite of a volcano.
  - masklinn 3mo ago
    No the seam at the center of the Atlantic is a mid-oceanic ridge, and it’s very much like a volcano since magma comes out. Icelandic volcanology comes from it being on the ridge. There are ridges off of the US coast (Explorer, Juan de Fuca, Gorda) but the ring of fire which surrounds the pacific is mostly subduction areas.
    - xg15 3mo ago
      Sorry, you're right of course (and yeah, the Pacific rim can obviously not be in the Atlantic, typed too fast there...) With "opposite" I meant the role in plate tectonics, in that classical volcanoes seem to mostly appear near subduction zones or hotspot but not on the ridges from what I know. (Iceland being the exception, but even there it's because of a hotspot that happens to be located right on the ridge) But I think the ridge system usually does not have volcanoes in the sense that there are magma chambers that fill up or cause eruptions. So the usual scenario of the "asleep supervolcano" does not apply. > The supervolcano complex under the Pacific is one of the largest known in the solar system, however. That sounds interesting. Do you have some links about that?

steve1977 3mo ago

The timelines don't really add up for me. So there could have been this hypothetical civilization 55 million years ago already. And they've only just disappeared (if they did) 10'000 or so years ago? Without a trace? Also, no, a conspiracy cannot be the answer to a question we've not yet asked. The word has a clear meaning, it requires people to conspire to hide something from you.

randomImmigrant 3mo ago
No. The idea is they could have lived and thrived for a few thousand years a few million years ago, then gone extinct.
- steve1977 3mo ago
  That's not what the articles says though: "Ancient mystical texts hint at earlier creation, the life that preceded the Garden, prequels to Genesis. These incarnations are not reported in the Bible because they are none of your goddamn business, but the evidence is everywhere. Some students of conspiracy believe there was a time when lizard people shared the earth with modern men, the older race dying as the younger emerged from the forest. The last of the lizards were worshipped as gods; these were the deities of ancient India and Greece. The technology—weapons and machines—created miracles. You can see the lizard kings in carvings from Mesopotamia, the oldest historical records, where humans bow before reptile men. You find them again in the Torah, where they appear as Nephilim..."
  - randomImmigrant 3mo ago
    That’s not the Silurian hypothesis the astrophysicists put out. That’s the author extending it to fit those myths.
    - xg15 3mo ago
      Yeah, the author is contradicting himself here: On the one hand, that civilization must have ended several million years ago, so erosion and plate tectonics had time to erase all traces - but on the other hand, humans were still having lively exchanges with those guys and viewing them as a normal part of their world in 10.000 BC...

Qem 3mo ago

Reminds me of this comic: https://badspacecomics.com/scour-copy-copy https://badspacecomics.com/scour-copy-copy

api 3mo ago

This is a good thought experiment to show how time is as vast as space. 400 million years ago is as distant as the stars. The Earth was a different planet then, in a sense. It’s also yet another Fermi paradox answer. Even if our civilization lasts for millions of years, that’s a blip. We are searching both space and time and both are incomprehensibly vast.

Razengan 3mo ago
> time is as vast as space. This is what I always say to "Why haven't we found any aliens yet??" Hell, we wouldn't even have known about the existence dinosaurs, lifeforms on THIS VERY PLANET, if we hadn't chanced upon their remains.
- api 3mo ago
  I’d also say that we do not know for certain that no dinosaurs, such as raptors perhaps, were intelligent enough for language and culture. At that age we can be pretty sure they did not have industry but they could have been like tribal hunter gatherers. If they did not build a lot and at large scale we’d have basically zero chance of finding anything. Stone, wood, animal skins, pottery, arrow heads, tools, etc., all that would be long gone. Metal would too but it might leave diagnostic traces, as would synthetic chemistry (plastics) or large scale fuel use. Birds, the modern still living closest relatives of dinosaurs, are often strikingly intelligent especially relative to their brain mass. Dinosaurs had small brains relative to body size but while there is a correlation there with intelligence it’s not perfect. There’s exceptions, animals with small relative brain sizes that seem very smart, like elephants.
hdgvhicv 3mo ago
How can a galaxy spanning civilisation fail. If life can spread to other worlds, unless you get FTL, how could you end all life in a galaxy As such it seems impossible for life to have reached interstellar travel anywhere in the Milky Way before at most a few million years ago, otherwise we would see it. Which is weird because life surely can’t be that rare in the entirety of space time. Of course the galaxy could be teaming with non interstellar life, but once you reach mankind’s level of sentience and technology it dormant seem a massive jump to interstellar, and once that happens there’s no way to put the genie back in the bottle.

jmclnx 3mo ago

>The oldest place on the earth’s surface—a stretch of Israel’s Negev Desert I do not understand this statement, I thought an area in Quebec was around 3 - 4 billion years old. I looked, seems Australia may have the oldest area: https://www.bbc.com/travel/article/20220126-is-the-pilbara-the-oldest-place-on-earth https://www.bbc.com/travel/article/20220126-is-the-pilbara-t... But I say the article could be true, but the only issue I have is the large dinos. I would think they could be an impediment to any organized settlements. One other thing, didn't most of our fossil fuels come from the Carboniferous era ? https://en.wikipedia.org/wiki/Carboniferous https://en.wikipedia.org/wiki/Carboniferous

delichon 3mo ago
The claim isn't about the age of rock, but that the surface has churned almost everywhere. Israel does contain the oldest measured continuous surface at about 1.8M yo, but nobody claims to have looked everywhere.
- DFHippie 3mo ago
  How churned is "churned"? Does this mean particular pebbles have have been found to have lain in their current arrangement for 1.8 million years, or just that not much has happened? I expect any arid region far from the poles or mountains and lacking dune fields will have similar patches of inert land. Much of Australia would fit this bill.

meindnoch 3mo ago

Joe Rogan tier pseudoscience.

markus_zhang 3mo ago

However, since we do have plenty of fossils from Silurian, it is hard to believe that none of the advanced technologies never left any hint. Any idea?

jerf 3mo ago
Yes. We'd find mines, where the richest veins were mined out and what's left is spread in a pattern that clearly appears to be "a rich deposit but with the best stuff taken already". The mine itself would have long collapsed but would also leave interesting evidence, a pattern of mismatched geological layers that rather than looking like an earthquake or a tectonic upheaval would be something that is relatively clearly shaft-shaped and if followed into the mountain would open out into a pattern that indicates intelligent mining activity as the anomaly is further charted. Places where there is suddenly a vast collection of foreign rocks from the other side of the world that can't be explained by glaciers. Radioactivity from nuclear tests that can't be explained by stellar phenomena and leave a layer of weird isotopes and isotope ratios all around the world, as we already have done. And while we aren't to the point we'd have found this quite yet necessarily, evidence on the Moon where unlike Earth evidence probably would in fact persist for millions of years, especially if it ever attained any scale, e.g., "a large complex of cities" might still leave a visible mark on the surface easily visible to modern satellites and clearly with no other explanation available as to what caused it. People get stuck on the idea that the only way to determine there was intelligent life earlier is to find a super complicated artifact which obviously can't survive, but there are footprints we've left in the world that are way, way larger than a cell phone or even a major city. I don't find it hard to believe we've lost entire human civilizations. In fact I'd call it the smart bet. Maybe those civilizations were even a bit more sophisticated than we'd have thought, with maybe an earlier and entirely unknown Iron Age popping up somewhere for some period of time or something. But this is the first major technological civilization this planet has ever seen, even across geological time scales. And those lost human civilizations never reached to the level where they took all the easy resources like we have, because if they had, we wouldn't be able to get them. Some resources we call "non-renewable" do replenish on a few million year time scale, but we also pull lots of resources out of billion-year-old rocks, such as copper mines in northern Michigan which are pulling resources out of pre-Cambrian rocks. Clearly nobody else has been there, at scale.

zabzonk 3mo ago

Dr Who and the Silurians had this covered: https://tardis.fandom.com/wiki/Silurian https://tardis.fandom.com/wiki/Silurian

atombender 3mo ago
That is explicitly referenced in the article.

hliyan 3mo ago

I don't think we have to go that far back. Plate tectonics, submersion and weathering does a good enough job of wiping the slate clean off the surface of the Earth, that any evidence of earlier hominids developing pre-industrial, coastal civilizations say, a million years ago, would be now under the crust. What we consider civilization is about 5000 years old, so it's not inconceivable that the cycle might have occurred multiple times during geologic time spans. Perhaps this is the first time civilization was not interrupted and made its way through to a technological civilization.

neaden 3mo ago
I mean sure, if they somehow didn't have any trade goods that went in land, didn't work with metals enough to do any appreciable mining, and didn't breed any plants or animals enough to change their genetics. Any hypothetical hidden past civilization would have to have been weird in a number of ways to not leave any evidence.
colechristensen 3mo ago
Huh? We have plenty of fossil evidence from, from your example, a million year old hominids. Far more than we would need to expect to see evidence of civilization. Subduction makes up for a tiny tiny proportion of where coastal land "goes" in any age. You'd need an enormous set of coincidences for a past civilization of hominids to go unnoticed.
engineer_22 3mo ago
>coastal civilizations say, a million years ago, would be now under the crust. Nah, you way off on that, coastlines have remained relatively same last million years, def not subducted into an ocean trench
mda 3mo ago
Are you sure? what about fossils and other remains? So far there is zero evidence that there was an advanced or non advanced civilization. Unfortunately this nonsense is the bread and butter ot pseudo archeologists.

amazingamazing 3mo ago

if all dolphins were wiped out could we know that they were ever here from physical evidence?

nkrisc 3mo ago
We’ll never know of the existence of most species that ever existed. Fossilization is rare.
- amazingamazing 3mo ago
  right, so how can one easily say this hypothesis is false? "advanced civilization" seems to be strangely characterized. would something a few steps above beavers be advanced enough?
  - vjvjvjvjghv 3mo ago
    How can anyone say the hypothesis is true? There is absolutely no evidence for it. It’s just a thought experiment.
  - krapp 3mo ago
    When people speculate about "advanced" ancient civilizations they usually mean said civilizations had technology at least as advanced as our own if not more so like nuclear weapons, antigravity, modern manufacturing and engineering, etc. A hypothesis that millions of years ago humans or some progenitor could build rough shelters out of sticks isn't particularly interesting.
    - nkrisc 3mo ago
      You don’t have to even hypothesize about other species that can create shelters out of sticks, they exist today.
  - nkrisc 3mo ago
    Typically the ones proposing a hypothesis have the burden of proof. Still waiting on any evidence in favor of the hypothesis. I won’t hold my breath.

dash2 3mo ago

I can't speak to dinosaur people, but the population genetics of our own DNA reveals that there were never many humans on the planet till recently, so that rules out any very large human civilization. (Unless they genetically altered themselves to hide the evidence! Ahaaa...)

graemep 3mo ago
If whole populations were wiped out and the world was repopulated by a small remnant would that not account for it? Or if an extinct human species had an advanced civilisation?
- throw1234567891 3mo ago
  No. That’s exactly how we know.
- AlotOfReading 3mo ago
  The founder effect differs between small populations filtered from a large population vs a smaller parent population. I want to point out that the silurian hypothesis is specifically about civilizations removed from us by geologic time. Advanced human precursor civilizations are much more effectively ruled out by the current evidence. Basically, a hypothetical precursor society either has to look very different from any we know about and materialize out of nowhere like alien colonists, or they didn't exist. For example, we know they weren't using large amounts of fire because nothing in the global charcoal records points to that. We know they weren't using plants that produce pollen because we don't find phytoliths with domestication indicators. We know they weren't using surface metals, because there was lots of that still around when the classically ancient civilizations started. We know they didn't contribute significantly to the gene pool. We have no material culture from them. We don't have a location on Earth they would have lived in. Etc.
  - deleted 3mo ago
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  - simonh 3mo ago

senshan 3mo ago

Isaac Asimov's Nightfall [0], but on a longer cycle? Jokes aside, what is the evidence, beyond "Ancient mystical texts"? [0] http://www.myths.com/pub/fiction/science-fiction/Asimov/Nightfall-and-Other-Stories.pdf http://www.myths.com/pub/fiction/science-fiction/Asimov/Nigh...

graemep 3mo ago
I think there is no evidence for it, but I think the point of the Silurain hypothesis (which the article does not convey well) is that if there were such civilisations we would not know as its unlikely we would find any evidence.
- senshan 3mo ago
  So it not a falsifiable statement from the onset? https://en.wikipedia.org/wiki/Falsifiability https://en.wikipedia.org/wiki/Falsifiability
  - vjvjvjvjghv 3mo ago
    I don’t think it’s necessary to falsify a statement that has absolutely no evidence for it being true.
  - jknoepfler 3mo ago
    It is falsifiable, in the sense that we have ample evidence of the many forms of life that have existed on earth... including fossil evidence, genetic evidence, preserved tissue samples and a long litany of other pieces of data broadly consilient with our understanding the biological timeline. On the other hand, we have zero evidence of Silurians or whatever. Those two observations are inconsistent and require explanation. Sure, one can hedge and qualify and excuse or whatever, and on pain of irrationality we have to allow that it's possible we're missing evidence of one of a bajillion possible competing hypotheses about intelligent life... but the theory most consistent with the evidence we have is that there wasn't any. That's falsifiable enough for me? The criterion of falsifiability pushed by positivists is kind of crappy anyway, it doesn't speak well to how we build models of the world while doing actual empirical work (and is itself non-falsifiable), but in practical terms idk, I don't see much to recommend the Silurian Hypothesis over the null hypothesis, so to speak.

Razengan 3mo ago

Petroleum could be the byproduct of a previous civilization. Also, just as we "engineered" animals and plants through selective breeding, previous animals/plants could have been the results of selective breeding by a previous civilization: There'd be no way to tell just as there'd be no way to tell our "tampering" a few million years in the future.

kergonath 3mo ago
> Petroleum could be the byproduct of a previous civilization. How so? We know how it forms, there is no real gap in understanding there. What could lead to the kind of distribution of oil and gas fields we can observe?
- Razengan 3mo ago
  Just fun to think about and base fiction on I mean, would an ant walking on a highway be able to tell that it's artificial?
  - kergonath 3mo ago
    Probably not, but an ant cannot do any kind of isotope analysis.
    - Razengan 3mo ago
      hah but again, would someone a million in the future be able to tell that today's bananas, corn, watermelons, cattle, dogs etc. were the result of selective breeding by an intelligent species? (with no human records for reference)
      - antisthenes 3mo ago
        > would someone a million in the future be able to tell that today's bananas, corn, watermelons, cattle, dogs etc. were the result of selective breeding by an intelligent species? They might be able to, based on when these disappeared, by comparing them to something more durable that is easier to date definitevely. All those organic things bred to fulfill the purpose of being useful to our civilization would very quickly disappear and become outcompeted by the undomesticated species. This sudden disappearance (along with the disappearance of more durable artefacts, like steel/plastics) might hint to someone that these species "are not like the others". Also by tying them to the cutoff in human remains (this is assuming humans disappear along with advanced civilization)

rdiddly 3mo ago

Interesting topic, but (to immediately veer off of it) I really wish he would find another word and stop misusing "conspiracy." The word has already been through hell.

ptx 3mo ago
That was my first reaction as well. The author seems very confused about it. He starts off defining it as something that is unknown or secret, and more specifically, he goes on to say, a secret "kept by a nefarious elite". I suppose secrets are usually associated with conspiracies, but a secret is not a conspiracy and conspirators don't have to be an elite. And then he says that in this case, it's the Earth itself that's conspiring alone. This contradicts all the dictionaries I consulted, which define it to involve multiple parties, which makes sense considering the etymology.

Robotbeat 3mo ago

Technical ceramics would have survived.

gradus_ad 3mo ago

I have a toy hypothesis that once civilization level intelligent life emerges it never disappears barring the planet it inhabits being vaporized by some unfortunately directed GRB or some similar catastrophe. Our knowledge is becoming holographic such that to prevent the reemergence of civilization one would have to wipe out all of us at once.

snapplebobapple 3mo ago
depends how you define civilization level life.if you mean we cant be bumped back to hunter gatherers without wiping out almost all of us, you are probably correct. If you mean we will always have computers and the ability to split the atom, i dont agree. Knowledge and industry is way more fragile and we have loat working knowledge of simpler processes in favor of more advanced ones so it wont be that easy rebuilding through the lower rungs of the tech tree.

aghilmort 3mo ago

Time Machine movie reboot did this in opposite direction into future decently well dude wind hundreds of thousands of years into future, sands of time, etc. modulo two warring biological descendants of humans not full diff species tho

tonymillion 3mo ago

The fact there is still coal(and oil) in the ground pretty much rules out any "advanced" industrialized civilization that came before us. I also use the Carboniferous Period as a metric as to why "Advanced alien life" isn't more abundant (and I believe it should be factored into the Fermi equation)... All those trees growing, soaking up sun, dying and just laying there to be compressed and buried without anything to decompose them, and then humans using them like solar batteries to power civilization (i.e. burning the coal), is one of those million-to-one things that enabled the human race to develop beyond basic society. We needed all that coal and oil (and gas) based power to get to the point - industrially and technologically - where we could even build solar panels or nuclear to replace them, so its not like you could start from first principals and jump straight to modern power generation either. The odds that the same sequence of events - fungus and bacteria not having the tools to decompose lignin (or whatever the alien equivalent is) - to happen on an extra-solar planet is ... pardon my pun ... astronomical :D (yes, I used a dash to separate ideas in a sentence, deal with it...)

inhumantsar 3mo ago
one thing I enjoyed about The Children of Time by Adrian Tchaikovsky: the spiders learned to build "computers" out of ant colonies by hijacking the ants ability to generate and respond to chemical stimuli. not that it makes me believe in the silurian hypothesis, but i'm always reminded of that whenever i start to think "well it couldn't possibly be done any other way".

dav_Oz 3mo ago

This article is a weird mash-up of an actually very interesting paper [0] with random personal slop like i've asked my rabbi, consulted my kabbalah-initiated friends and for the fun mixed it up with some fashionable ancient text (Mahabharatha) So maybe just stick right to the paper itself and its clearly stated motivation? > Perhaps unusually, the authors of this paper are not convinced of the correctness of their proposed hypothesis. Were it to be true it would have profound implications and not just for astrobiology. However, most readers do not need to be told that it is always a bad idea to decide on the truth or falsity of an idea based on the consequences of it being true. While we strongly doubt that any previous industrial civilization existed before our own, asking the question in a formal way that articulates explicitly what evidence for such a civilization might look like raises its own useful questions related both to astrobiology and to Anthropocene studies. Thus, we hope that this paper will serve as motivation to improve the constraints on the hypothesis so that in future we may be better placed to answer our title question. [0]https://www.cambridge.org/core/journals/international-journal-of-astrobiology/article/silurian-hypothesis-would-it-be-possible-to-detect-an-industrial-civilization-in-the-geological-record/77818514AA6907750B8F4339F7C70EC6 https://www.cambridge.org/core/journals/international-journa...

ma2kx 3mo ago

I think the article greatly underestimates our archaeological capabilities. We can identify five mass extinctions in the last 500 million years, so why should such a civilization simply be overlooked? Of course, we wouldn't find abandoned ruins, but the idea that an industrial civilization wouldn't leave behind any detectable artifacts is practically impossible. Perhaps there were a few primate species before that could make fire and hunt with bows and arrows, but certainly nothing industrial and hardly any extensive agricultural culture.

RunSet 3mo ago
> I think the article greatly underestimates our archaeological capabilities. "they found a single forerunner to their idea of deep time. It came not from science, but from science fiction. At this level of conjecture, there’s little difference. It was an episode of Dr. Who" also betrays an ignorance of the trope originator.[0] [0] https://en.wikipedia.org/wiki/Serpent_Men https://en.wikipedia.org/wiki/Serpent_Men

jake_and_fatman 3mo ago

I'm butt hurt that I'm five paragraphs in and still have no idea what the hypothesis is.

GolfPopper 3mo ago

From author and druid John Michael Greer's essay, "The Next Ten Billion Years"[1], "One hundred million years from now: The universe has a surprise in store for the corvins, though. Their first moon landing included among its goals the investigation of some odd surface features, too small to be seen clearly by Earth-based equipment. That first lander thus set down on a flat lunar plain that, a very long time ago, was called the Sea of Tranquillity, and so it was that the stunned corvin astronauts found themselves facing the unmistakable remains of a spacecraft that arrived on the moon in the unimaginably distant past. A few equivocal traces buried in terrestrial sediments had suggested already to corvin loremasters that another intelligent species might have lived on the Earth before them, though the theory was dismissed by most as wild speculation. The scattered remnants on the Moon confirmed them, and made it hard for even the most optimistic corvins to embrace the notion that some providence guaranteed the survival of intelligent species. The curious markings on some of the remains, which some loremasters suggested might be a mode of visual communication, resisted all attempts at decipherment, and very little was ever learnt for certain about the enigmatic ancient species that left its mark on the Moon." 1. https://www.resilience.org/stories/2013-09-05/the-next-ten-billion-years/ https://www.resilience.org/stories/2013-09-05/the-next-ten-b...

xg15 3mo ago
What an amazing read! (and only slightly depressing) Though I'm kind of disappointed the last section did not end with fusion power, stellar migration and artificial intelligence...
gtowey 3mo ago
Funny, as I was reading the original article, I was thinking that anything left on the moon would survive being recycled by plate tectonics. It seems like reaching the moon isn't such a stretch for any technological civilization, so the lack of preexisting artifacts counts as pretty definitive for me.
- saidnooneever 3mo ago
  point at a spot on the moon which was not hit by an object, its not easy. very big things have hit it too. additionally radiation is much more so decay is accelerated a lot? (might be wrong but i think so?)

netbioserror 3mo ago

To recognize the possibility, one has to grapple with incredible scale and deep time: In roughly 300 million years (1/10th of the time life has been around), the Appalachians split off from the Atlas; the Atlantic Ocean first started splitting open; uplifts underneath North America pushing the West up from the seabed and caused the rivers to carve millions of acres of sandstone landscape down, leaving towering plateaus, cliffs, and eventually river chasms. Over the 3 billion years before that, what was carried away like so much sediment? What was subsumed by subduction boundaries? On a much more recent timescale, one of the dominant theories of the emergence of civilization places the ancestors of the Sumerians in a stupendously fertile valley at the bottom of what is now the Persian Gulf, eventually flooded during the retreat of the glacial maximum and covered in Tigris & Euphrates sediment. It could be the very origin of regional flood and primordial garden myths. But it's all buried.

davidbjaffe 3mo ago

Silurian Hypothesis, SETI, a widely help motivation for space exploration, much of sci-fi: all posit a high-ish rate of life (or intelligent life) invention, because the alternative is terrifying. I/we need/enjoy this, but it's fiction. When humans reason about the rate, they're extremely biased by what they want to be true.

ohthehugemanate 3mo ago
+1 in general that anthropic bias is strong, but it cuts both ways, even in relatively hard nosed statistical models (@see Drake equation vs Rare Earth hypothesis). Truth is, there are a ton of factors we just can't observe (yet?) that play a big part. For example, since the rare earth hypothesis was published, we know a lot more about exoplanets, and earth-range size in the habitable zone of a stable star and galaxy appears much more common than we thought. But we don't know if plate tectonics are really required, or gas giant "vacuum cleaner" planets int he same system, or even oxygen. But we do know that the minimum value for intelligent species is at least 1, because we exist. For me, it's carl sagan's "invisible dragon" comparison that sticks in the back of my head. If there's intelligent life out there (or in earth's ancient past) but there's no physical way to detect or know it... Then like the invisible dragon in mu garage, it's the same as not existing. Maybe we'll develop new techniques and gather new evidence, but until we figure out how to bend spacetime for FTL anything, or find clear evidence, we should act as if it isn't/wasn't there. So TFA says that 55M years ago there was a climate fluctuation that looks similar to the anthropocene one. Good start. But interpretation of ancient stories across cultures is practically the definition of anthropic bias. We have to wait until there is real evidence that the temperatuee bump was dragonfire and not my heating system acting up, to ascribe cause.

SilentM68 3mo ago

I really enjoyed this article. It was a very pleasant read. The author should write a book and or movie script. The original Doctor Who Silurian episodes were fun to watch. Makes sense to connect dinosaurs or the remnants of Silurian civilization to dragons and deities. Star Trek Strange New Worlds S04E01 deals with the dinosaurs and Mars @ 65 million years ago. The story is rather intriguing and fun to watch as well. Invincible S04E04 deals with the various ages that planet Earth has gone through and has a different take on the meaning of Hell and Satan and why they exist. Last episode of the Season 4 is rather interesting, as well as it relates to the possible next phase or not, of human evolution.

mcswell 3mo ago

I wrote a sci-fi short story on this idea once. It took place in the present, and left the truth of the hypothesis open. Submitted it to Analog, but it was rejected. I suppose there are now places one can self-publish sci-fi stuff, but I'm not sure I can even find my original. Edit: Did a Linux find, and...it did find the story. Unfortunately, it didn't find me a place to publish it.

gorgolo 3mo ago

Surprised so few are pushing back against some of the claims in this article. Eg that the entire surface of the earth gets replaced in a million years by tectonics. Many of the large plates are more than 1000km across, they’d need to be moving meters per year for that to happen. In reality it’s cm per year. Also typically it’s oceanic plates that get subducted and take material under the crust, not continental plates. If it were true, then how do we see dinosaur fossils, and creatures even older than that; how do we find rocks that are over a billion years old. This doesnt reject the possibility that there was a civilization tens of millions of years ago, but it makes the article hard to take seriously. If you’re gonna spend time writing an article on this you might as well try to research it a bit more. Someone is gonna read this and repeat this nonsense like it’s some fun trivia.

JPLeRouzic 3mo ago
> Many of the large plates are more than 1000km across, they’d need to be moving meters per year for that to happen. In reality it’s cm per year. A plate moving one centimeter per year would move over 10,000 km (6000 miles) over a million year, isn't? It's two times the distance from New-York to San Francisco, one fourth of the Earth circumference! And the Cretaceous–Paleogene extinction event was approximately 66 mya.
- ben_w 3mo ago
  > A plate moving one centimeter per year would move over 10,000 km (6000 miles) over a million year, isn't? No, 10,000 km is 10e6 meters, or 1e9 cm, so at 1cm/year it would take a billion years, not a million.