Was there a civilization on Earth before humans? | Hacker News Reader

Was there a civilization on Earth before humans?

theatlantic.com

366 pointslimbicsystem262 comments

This is one of my all-time favorite “what if” questions. Some years ago a friend of mine coily posed this same question to me: What does humankind make that would survive 60 million years into the future, and if some other advanced industrial civilization had existed 60 million years ago, how would we know?

It turns out my friend had put a LOT of thought into this exact question. Enough to do a masters in geology, his work ultimately making it into a high profile journal with writeups in places like the NY Times.

He started talking to various geologists about what might survive as telltale markers of our civilization. Buildings or structures of any sort? Ha! Statues and monuments? Maybe we’d notice the odd deposit or two of minerals.

After going through a long list of candidates, he settled on carbon cenospheres. These are little balls of carbon almost exclusively made in internal combustion engines as the result of aerosolizing fossil fuels. Sixty million years ago, our love of the ICE will show up in the fossil record as a light dusting of cenospheres covering the earth—contemporaneous with massive numbers of species going extinct due to mankind’s other influence.

And as my friend was telling me his story, this is where my hair stood on end. Sixty million years ago we see a massive species extinction... and a light dusting of carbon cenospheres covering the globe.

But we also see unnatural levels of iridium at the same point. And, while it’s hypothetically possible some industrial civilization was mining iridium and blanketing the globe with it, it’s more probable that the iridium was delivered by an asteroid.

But how would you know? So my friend, as part of his research, went taking samples of his cenospheres from around the globe. What he found was interesting: namely, the further one gets from the Yucatan (where scientists had already validated there was an asteroid strike), the cenospheres get smaller. The big heavy ones precipitated out of the air closest to the Yucatan asteroid strike. Hardly likely to be coincidence.

So much for ancient civilization this time around.

However, his work rewrote a critical understanding of the KT asteroid extinction event. Namely, we previously thought most of the carbon at the KT boundary was the result of giant forest fires ignited by the strike. However we now know that the strike must have aerosolized massive oil fields under the Yucatan at that time and set them ablaze.

Not a bad contribution to science starting from a sci-fi premise!

He’s not too far off what this article suggests as a marker of civilization in the past. But they have positives!

“Fifty-six million years ago, Earth passed through the Paleocene-Eocene Thermal Maximum (PETM). During the PETM, the planet’s average temperature climbed as high as 15 degrees Fahrenheit above what we experience today. It was a world almost without ice, as typical summer temperatures at the poles reached close to a balmy 70 degrees Fahrenheit. Looking at the isotopic record from the PETM, scientists see both carbon and oxygen isotope ratios spiking in exactly the way we expect to see in the Anthropocene record. There are also other events like the PETM in the Earth’s history that show traces like our hypothetical Anthropocene signal. These include an event a few million years after the PETM dubbed the Eocene Layers of Mysterious Origin, and massive events in the Cretaceous that left the ocean without oxygen for many millennia (or even longer).”

What happens to the atmosphere when you suck all the oxygen out of the oceans?

Also, how long would it take for the oceans to reabsorb that oxygen? Do the current records follow these expectations?

Perhaps there are proxy signals? For example, there's ocean re-oxygenation faster (or slower?) than expected? Could a species that required more oxygen tip the scales?

Wouldn't you find human artifacts all over the place even 60 million years from now? We have fossils much older than that, so wouldn't many many objects like gold wedding rings be around 60 million years from now?

I don't think any of that would necessarily be indicative of civilization, though.

Yes, absolutely. The article is borderline clickbait. If there were a technological civilization on Earth in the past, we would have detected it by now. Concentrations of radioisotopes, industrial ceramics, signs of large excavations in the fossil record... those are just a few.

Those are just few that presuppose it would have to be an industrial civilization at our level ("concentrations of radioisotopes")...

Radioisotopes decay; which isotopes are you thinking of that have half-lives of millions of years and would be found in detectable quantities?

(I was going to raise the same point, thinking of low-background steel and the effects of nuclear testing on our atmosphere, but after some more reading it appears that most of those isotopes decay over shorter periods or weren't sufficiently elevated to be discernible from the background, if it were being examined in the far future.)

Radioisotopes decay, but it is the ratio that is important. We know, for example, that a natural (we assume?) nuclear reactor occurred in Africa 1.8bn years ago due the different isotopic concentration of uranium deposits from that era.

Wondering about this as well. INAG, but I think fossils are extremely rare relative to population. And things like wedding rings will have disintegrated after just a few million years. But still, you'd think some of them would survive under conditions similar to those that preserved dino skeletons?

That was my thinking as well, though apparently geologists are pretty pessimistic about both the survival of human artifacts and the probability that someone would find the rare oddballs that did survive.

Plus, it’s possible that some hypothetical dino civilization mastered bio-degradable materials early on before taking to the stars ;-)

and settled the ...delta quadrant it was iirc? :)

Just a misread of the data by a well-intentioned scientist and some meddling humans.

And now they're back, to reclaim what was once theirs.

Invasion of the Space Dinos!

That is more-or-less the plot of more than one episode of Dr Who:

http://tardis.wikia.com/wiki/Dinosaurs_on_a_Spaceship_(TV_st...

http://tardis.wikia.com/wiki/Silurian

"Dinosaurs on a Spaceship" was mildly disappointing given the amazing ridiculousness of the title, but "The Hungry Earth" / "Cold Blood" is a top-notch two-part episode. It feels so authentically human in both the highs and the lows.

Also reminiscent of an episode of Voyager where dinosaurs had evolved on earth millions of years before humans and started exploring space.

http://memory-alpha.wikia.com/wiki/Distant_Origin_(episode)

How optimistic are geologists regarding the survival of bones? Or small insects?

They discuss that in the article. Essentially everything would be turned asunder by the changing of the earths crust. The oldest part of the earths crust is something like 1.7 million years.

Then how would we have dinosaur bones from 65 million years ago +?

Fossils represent a very tiny portion of whatever was there at that time.

Yes, but the point is the 1.7 M number for total crust turnover can't be valid, as none of that tiny portion would still exist.

I find it hard to believe that there won't be at least some human fossils lying around 60 million years from now.

It’s an angle that a funeral directors could use as a selling point - Fossilisation.

see Ancient Egypt

In Gene Wolfe's SF/fantasy tetralogy The Book of the New Sun, set very far in the future, he refers to corpses preserved by extreme means and rendered essentially indestructible and basically just cluttering up the world.

We don't have bones, we have fossils.

Fossilized bones (plus the occasional feather/tissue), and way to miss the point.

Not trying to be pedantic but the devil is in the details.

Bones are common, fossils are formed by a relatively rare geologic process. Fossilization supplants slow to rot organic material with stone, embedding it in the strata, in just the right conditions. It's unclear to me what (if any) industrial rememants would become fossilized and if they'd be recognizable as such.

Given that pillow lavas can be recognised in some eclogite facies rocks, I think a porcelain toilet would stand a good chance of remaining recognisable at all the way to granulite or eclogite facies, as long as it is not too deformed.

Pyramids? Statues? Stuff that is already made of stone to start with?

How long has it taken the pyramids to decay to their current status?

If I'm not mistaken, Greenland has crust from over 3 billion years ago. 1.7 million years ago is nothing, I don't know where you got that number from but it is wrong.

The article.

“For example, the oldest large-scale stretch of ancient surface lies in the Negev Desert. It’s “just” 1.8 million years old—older surfaces are mostly visible in cross section via something like a cliff face or rock cuts. Go back much farther than the Quaternary and everything has been turned over and crushed to dust.”

The article refers to ancient surface, as in, the oldest place that we can find that has continuously been an exposed surface. The take away is that most areas don't remain stable at the surface, either they erode away, or get buried via sedimentation.

The article is in no way stating the oldest bit of the Earth's crust is 1.8 million years old. Crust has a specific meaning, the chemically differentiated rocks at the surface i.e. everything but the very very rare bits of exposed mantle. Oldest oceanic crust is <200 Ma, oldest continental crust dates to the Hadean (4.4 Ga, if you set the bar at only zircons).

All comments in a thread based on an article should be read in that context. Unless, of course, the links are never followed and we’re just here to massage each other’s preconceptions.

As does much of northern Canada. However, the ancient rock, billions of old as it may be, wasn't surface rock 1.7 million years ago. It's only been surfaced since through erosion.

> The oldest part of the earths crust is something like 1.7 million years.

Wasn't the article more meaning "the oldest part of the earths crust, that's still on the surface"?

eg everything else has been buried, or destroyed, via other geological processes

This is kind of the "why aren't we all buried in bones" question that YECs raise. Very little makes it into the fossil record -- fossilization is sensitive to a lot of different conditions, and then someone's gotta find it later besides.

Going past a few tens of thousands of years, fossils start to either be of very large things, or of very large communities of small things.

I'd be surprised if any future scientists could find even a single piece of modern jewelry a million years from now.

Why though? At least gold is very nonreactive, isn't it?

It's also extremely soft (for a metal). Fossils survive in part because they are reactive and become harder in certain specific conditions.

It's also very soft

Sure, but that doesn't make it immune to the passage of time.

Take Mesoamerican gold for instance: only about a thousand years have passed since much of it was made by humans, but it's still considered a rare and valuable archaeological find. (Granted, it was produced in smaller quantities than today.)

Gold is melted by fires; gets scattered and buried by a million years of bioaccumulation; seas move, rivers appear or disappear, continents drift a little, climate changes, glaciers come and go and further destroy evidence.

Google is feeding me a lot of really dumb stuff at the moment when trying to come up with numbers, but I'd guesstimate that most traces of our civilization would be buried a hundred feet below the surface after a million years' time. That makes it pretty difficult to find small things.

Mesoamerican gold was looted and melted down wholesale (along with a lot more silver) by the Spanish. The artefacts were considered unchristian and so were deliberately destroyed, and this has meant that we have barely a fragment of the artistry of the Inca and Aztec.

There is some hope though! It's thought that the melting process was done in Spain so as to allow a reliable royal assay, if so then some of the ships that sank in the trade may have holds full of crushed and squashed precious artefacts.

That’s interesting, can you provide any citations?

Mesoamerican gold is quite common in the gilded church alters of Spain.

There are tons of small fossils. There’s a 50M year old fish in my son's room that’s about an inch long.

Granted the coral fossil in the living room is many small animals, but it’s not a big object.

Right, I had fossils like that as a kid too, and even had a friend with a ranch in the East Bay that had an exposed fossilized seabed with lots of fossilized shells.

But typically those are extracted from deposits with lots of similar pieces, like the three-foot-long slab of fossilized seabed I had. Professionals might carefully carve something like that up and turn it into lots of small fossils of fish, but they all came from the same chunk of rock.

That's what I meant by "large communities of small things".

So, it's possible that some bunker of physical storage of wealth, with gold bars for instance, will survive a hundred thousand years longer than most of the rest of our civilization. Or, maybe one of our many many landfill deposits will end up with just the right conditions to preserve for a long time the preservable stuff. But I don't think bits of gold jewelry will just be sifted out of the dirt.

Come to think of it, the best bet for evidence of our civilization a million years from now are currently the bits we've left behind on the moon, and Musk's roadster! (The latest calculations have a 6% chance of it crashing back to Earth within the next 3.5 million years -- but it will continue to swing back around every hundred years or so until then.)

What about steel? Carbon fiber? It’s hard to imagine that fossils survive while a million tons of steel framing for a skyscraper would not.

The process of fossilization by definition replaces organic material with very hard minerals. The fossils we find today are the ones that by chance have fossilized into the hardest minerals under the best conditions for preservation -- buried in the right kind of mud at the time, or by tar more recently, or in ice, or in a bed of limestone.

I can find one not-great reference suggesting that carbon fiber items are expected to be in landfills for on the order of hundreds of years -- not very long in geological scales. Steel rusts and degrades spectacularly easy, and a lot of the steel we've produced is exposed to conditions helping it along.

Neither of these items is susceptible to the process of fossilization; it's that process that helps preserve some things for a long time. The stuff we make has to last that long all by itself, and we're not that good at making things yet.

I'd expect ceramics to survive better than steel. A lot of our archaeological artefacts from former human civilisations are ceramic.

I had some interest in this question a decade or two back. What I found from my searches was that it was thought that some human-made ceramics were tough enough to last a million years, pretty much nothing else. How much longer, IDK. Ice sheets will wipe out large structures like the dams and pyramids, but how long will it take to destroy or scatter the remains so that they are not recognizable?

Gold is soft (and heavy), it will be ground to flakes or completely misshapen over millions of years. Erosion and tectonic keep everything moving.

Gold is soft but Amber is softer and we've found intact insects encased in that substance which are 230 million years old*. You wouldn't be likely to find a complete car or something in 60 million years but there will certainly be plenty of artifacts which were preserved through sheer luck. I wouldn't be surprised if most small manifactured objects would survive in archeologically recognizable form if they were accidentally lost in an anoxic environment. For example, imagine you lose your iPhone when out in a swamp. Drop a phone in something as thick as Pluff Mud, which is abiotic below the surface, and you've basically encased it in the exact kind of environment which has produces the best fossils we've yet found.

My thought is how likely is it that crustal movements would bury things too deep on that timescale? If stuff stayed near the surface, that's one thing, but would it?

We also see things trapped in glaciers, but if the timescale is large enough for all the glaciers to have melted...

Here's the paper:

https://pubs.geoscienceworld.org/gsa/geology/article-abstrac...

That’s the one! I was hoping someone would be interested enough to fact check me :-)

> Not a bad contribution to science starting from a sci-fi premise!

1. Ancient civilization enters industrial and post-industrial era.

2. Carbon levels rise, so do global temperatures.

3. In a desperate attempt to save themselves they try geo-engineering by slamming a massive asteroid in the too hot and thus unpopulated area of Yucatan.

4. Goes wrong.

I can see it working as sci-fi novel

If you write it, I'll buy it.

This reminds me of the movie Snowpiercer

As far as geo-engineering goes, I think what they'd be wanting to do is cause a super-volcano or three. You really don't want to be pulling asteroids down - just a couple of finely place nukes will do. Get a volcano going, put a few tons of sulphur in the air and you have a nice cooling effect. Just be careful of the unintended tsunami. Should probably just evacuate Iceland and keep popping the volcanoes until it's cool again.

Is there any theory that suposes this might happened, on a small scale, and the temps (and crust) warm? Could that loosen things up, so to speak, and trigger more volcanic activity?

Perhaps the asteroid was just an asteroid mining operation gone horribly wrong, or some form of planet killing warfare?

Maybe the Earth-based technological civilization attracted the attention of a space-faring civilization, who dropped an asteroid to wipe out the Earth civilization (successfully, as it turns out).

Which means maybe we should be a bit more careful about bleating our existence out into the universe these days...

People who had this thought have also liked "The Dark Forest" and "Death's End" by Liu Cixin :) (These are part 2 and 3 in the "Three Body Problem" series.)

And in the 1970s by Gregory Benford, In the Ocean of Night.

And Footfall by Niven and Pournelle. And the Galacti Milieu series by Julian May.

Also 'The Forge of God' [0] by Greg Bear [1987]:

"We've been sitting in our tree chirping like foolish birds for over a century now, wondering why no other birds answered. The galactic skies are full of hawks, that's why. Planetisms that don't know enough to keep quiet, get eaten".

[0] https://en.wikipedia.org/wiki/The_Forge_of_God

Yes, it makes you realize this pop song from the seventies is not only incredibly cheesy but could be catastrophically dangerous

https://www.youtube.com/watch?v=_BrSVOOK610

How about:

- bacteria with engineered enzymes for recycling (https://news.ycombinator.com/item?id=16856246) mutate/go wild and wipe out most/all traces of civilization

- what we can find today is just slightly elevated levels of whatever these bacteria mostly ignored.

I'm confused though - the oldest fossils are 3-4 Billion years old? Is the hypothesis that we just haven't stumbled on creatures of this time?

Sure, the KT event isn’t the result of ancient civilization, there's nothing saying we couldn’t have had civilization at some other point in time, or that didn’t leave a record noticeable to us from that time.

They cremated their dead for fear their decaying bodies would corrupt the Earth (or their karma or their gods or whatever). And voila, they're gone.

This is implausible; you're assuming that every civilizational stage from every point in this hypothetical species development would have had the same burial practices?

Though, I'll grant it's possible they could've been soft-bodied creatures that leave very little in the fossil record or might otherwise look ambiguous to us. A future civilization looking back on human fossils might think we lived no differently than any other Hominidae. Anatomically modern humans have been around for ~2.5 million years, if our civilization were to end in even another couple million years that would still be a fairly tiny window in which we developed the intelligence to create civilization and then went extinct. If some jellyfish species developed human-level intelligence 300 million years ago and then went extinct in the same window, it's entirely possible we wouldn't be able to recognize the difference between their fossils and those of their less intelligent ancestors/descendants.

What about the ring of debris in geostationary orbit? Will that decay in 60M years?

And the stuff at the Lagrange points, assumedly in rather stable orbits.

To answer both of your questions: none of that stuff will be in orbit in 60m years.

Geostationary is only stationary in relation to a specific point on earth (geo). It just means it stays above a point on earth. It requires regular minor adjustments.

L1, L2, and L3 aren't stable. L4 and L5 are... but you would still need to adjust for the earth and moon not being perfect spheres; the moon moving slowly away from earth; tidal variations; solar wind; debris; etc.

L4 and L5 would last the longest, but not 60m years.

Could you move in a moon orbit?

Same problem. I don't think it could be in orbit.

Someone else mentioned the objects we've placed on the moon. Seems to me that those would last the longest. The moon gets hit by small meteorites daily, but nothing that would destroy what's up there.

>none of that stuff will be in orbit in 60m years. where will it go? it wouldn't have the drag or the delta-v to reenter. i think the parent meant geostationary altitude, but "geostationary" orbits are "relatively" cyclically stable. most significant perturbations, you mentioned some, are all <100 year cycles. If there was another spacefaring civilization >60m years ago i think there would be evidence, in orbit.

What about the rovers, plaques, and flags on the moon?

> What does humankind make that would survive 60 million years into the future, and if some other advanced industrial civilization had existed 60 million years ago, how would we know?

I wonder if a swarm of artificial satellites that are little more than time capsules on various highly stable orbits, combined with radioactive markers/beacons on the moon that is arranged to somehow point towards the swarm, might survive that long? The moon's orbit is stable on the order of billions of years [1], but surface impacts might bury any artifacts we leave, so radiation is likely the only way an artifact can stand out millions of years from now.

If the swarm is a solid procession of one satellite passing near the Earth once every 50 years, then the markers' arrangement might be able to point to that intersection somehow. Bonus points if we can figure out passively-controlled, self-repairing solar sails for better detection. I haven't sketched the math yet though, so I don't know if we're talking about more satellites than we can create (would more than likely require von Neumann mining bots on an asteroid to produce, and definitely more mass than we can realistically lift at this time).

This has the advantage of letting us continuously launch updated capsules, as well as capture and update probes (like modifying a massive continuous loop) if our civilization lives that long.

I really Iaian Banks' idea of a civilization "restart button": deep space-resident AI-manned ships that all but just wander and hibernate within vast gulfs of vacuum, equipped with the tech necessary to reboot their civilization, and run silent all the time except when they opt-out of the service. That requires AGI and a fictional inexhaustible energy source to pull off, so we have to settle for what we can do for now.

[1] https://astronomy.stackexchange.com/questions/19658/what-def...

Interesting. Thank you for that.

Some years ago a friend of mine coily posed this same question to me

In this part, I think you meant coyly which has a different meaning from coily.

Yup, my undergrad journalism profs would be moritified. In my defense, it was early and I was still working on my first coffee.

If I had a penny for each time I used the wrong word I'd be riff.

What about artifacts on the Moon?

Long since buried by moon dust.

I'm unclear why they would be buried, there's no Moon-wind storms as far as I know.

Footprints from the Apollo missions can still be seen.

Anyways, I was thinking that the metal from the spacecraft wouldn't have gone through the weathering/oxidation that anything man-made still on earth would go through.

Long poles anchored everywhere around the moon.

Even if some of them will get covered by dust and some get destroyed by asteroid impacts, the others will remain visible.

You don't get a better anoxic environment than space!

Moon artifacts would be there for a very very long time, and yes there would be no burying, techtonic activity, or oxidizing. Only impact events and solar wind really change the moon, the former is rare now and the latter insignificant. Evidence of a human presence on the moon will be there for potentially at least a billion years. The footprints might last that long, and actual artifacts made of metal (including gold) surely will.

Over 20 years ago, I read a good sci-fi story which I would love to see in a movie; the book is “The Ice People” by Barjavel (French author).

Article on Wikipedia: https://en.m.wikipedia.org/wiki/The_Ice_People_(Barjavel_nov...

Highly recommended! At least from my recollection!

Excellent book

> if some other advanced industrial civilization had existed 60 million years ago, how would we know?

Wastes, particularly those that get everywhere such as plastics.

I am told that one long-term marker of human presence on earth at this time is that strata being laid down at present contain small pieces of plastics.

See "The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene" https://www.sciencedirect.com/science/article/pii/S221330541...

Also:

"Human impact has created a 'plastic planet'" https://www.sciencedaily.com/releases/2016/01/160127083854.h...

http://www.newsweek.com/theres-even-more-plastic-ocean-floor...

https://www.theguardian.com/environment/2017/feb/17/tiny-pla...

edit Even though it will change over time into something other than plastic,

1) it will affect the composition of rocks being formed now

2) through sheer ubiquity, some of it is likely to enter into the fossil record.

I have a hard time believing plastics will persist as plastics. It doesn't take much heat to denature most plastic, and geologic sediments tend to experience a good bit of pressure and heat over time.

I doubt that they will be the same after a few million years, no. But what kind of rock will it make? Won't it be unlike anything else?

Aren't plastics hydrocarbons? Would the hydrogen be driven off (cracked) leaving something like coal.

I think that we might be more likely to find concentrations of metals left over from artifacts of civilization. If so, would these look different from naturally occuring metals?

Yes - I find it hard to imagine I-beams couldn’t be found embedded in a geological layer somewhere.

Very few large things make it into the fossil record ( https://news.ycombinator.com/item?id=16837795 ), and a small fraction of those are discovered. It's possible, but I-beams are rare compared to plastic particles, which are basically carpeting the seabeds, rivers and beaches now.

"microplastics everywhere". http://www.bbc.co.uk/news/science-environment-43363545

"Microplastic pollution in oceans is far worse than feared, say scientists", "pervasive and persistent nature" https://www.theguardian.com/environment/2018/mar/12/micropla...

"The deep sea is a major sink for microplastic debris" http://rsos.royalsocietypublishing.org/content/royopensci/1/...

We don't know what the effect of millions of years on this debris will be, but I am suggesting that due to the fact of the human species as a geological force, most of the rocks from this era will be a bit unusual in composition.

I-beams would dissolve into rust very quickly.

Your best bet for metals might be gold as it is not typically reactive with water or oxygen. And as a reminder, we do sometimes find solid blobs of gold... :-)

Agreed about the gold. That came to mind also.

I also agree that the I-beams would rust away, as would rebar embedded in concrete. Would they remain as identifiable shapes or would the material migrate?

"remain as identifiable shapes" is basically fossilisation, which does happen. And it likely applies to I-beams as much as it does to coke cans, plastic bottles and cigarette buts. Except that the latter are going to be much more numerous.

So you're pretty sure the OP's geologist friend is mistaken?

I'm not certain of anything, but as for "OP's geologist friend" I would like to hear the comments of someone with the relevant domain knowledge on the long-term fate of all of these plastic particles.

Maybe WE are the waste.... Former civilization created organic automatons for amusement. The civilization is long gone, but their relics continue on to this day in the form of 'life'.

> What does humankind make that would survive 60 million years into the future

Nuclear reactors are recognizable for their crazy isotope distributions for billions of years. Geosynchronous sattelites might be stable for that long, too. The anthropocene mass extinction is likely to show up in the fossil record, and the rapid climate change based on burning carbon out of the ground (which doesn't match the isotope mix of atmospheric carbon) will likewise be detectable from sediment.

But I suppose that the weird isotope distribution caused by nuclear reactors affects areas so small, that they would be incredibly unlikely to be detected?

It's not like you can smell it, but these things exist (from natural fission chain reactions, not progenitor civilizations!) and have been discovered: https://en.wikipedia.org/wiki/Natural_nuclear_fission_reacto...

I'm sure it's a dumb question, but it's a genuine one. How do we know that the Yucatan crater is from an asteroid, and not from some kind of man-made explosion created by an advanced civilization?

Bomb explosions look fundamentally different from meteorites. Both may be modeled by modern tech.

Basically: because it has a lot of characteristics in common with all the other, better preserved, asteroid craters we know of. So our hypothetical advanced civilization would have to have deliberately mimicked all the little details of an asteroid impact, not just created a big explosion using some other method. That's possible, of course, and if they did it well enough we'd never know. But it seems much more plausible that it was an asteroid impact.

Maybe they had started asteroid minding and in an attempt to bring one into local orbit, it went horribly wrong.

It's definitely an asteroid.

What we can't know is if someone aimed it there.

Fun fact, Yucatan means "I do not understand".

https://en.wikipedia.org/wiki/Yucat%C3%A1n#Origin_of_%22Yuca...

The page provides several alternatives, ending with "the Chontal Maya people refer to themselves as the Yokot'anob or the Yokot'an, meaning "the speakers of Yoko ochoco." Thus Yucatan most likely derives from Yokot'an."

While this is marked as "citation needed", given the information provided, it seems illogical to prefer one of the other explanations just because it sounds more amusing.

Also see: https://en.wikipedia.org/wiki/Chontal_Maya which seems to at least confirm the term "Yokot'an" exists.

It is probably specious reasoning to assume that the name originated at the moment the Spanish first met the indigenous people, but it seems to be such a good story that most don't question it, even when they are debating the different possibilities.

"But how would you know? So my friend, as part of his research, went taking samples of his cenospheres from around the globe. What he found was interesting: namely, the further one gets from the Yucatan (where scientists had already validated there was an asteroid strike), the cenospheres get smaller. The big heavy ones precipitated out of the air closest to the Yucatan asteroid strike. Hardly likely to be coincidence."

I am reminded of the famous talk by Richard about "where does fire come from, where does. plant get Carbon, well it gets it from the AIR, and it grabs water from the earth, and the flame that you see in fire is the energy from the sun being released!" (Paraphrasing, [0] )

so my point is, that if you look at Plant Life distribution and look at all of South America, with their dense rain-forest plant biome - you have a crap ton of plants which may have had the ability to absorb more carbon based on the Yucatan crater (gulf of Mexico) and thus thrive based on the abundance of the carbon flood that happened during this impact.

[0] https://www.youtube.com/watch?v=ifk6iuLQk28

This is the best explanation of fire/plants/atmosphere that I have ever heard.

---

Question:

Why would oil concentrations happen in the places they do over many billions of years?

So why would the seemingly devoid-of-water places on earth (Middle East) be oil rich, where, at the same time, South America also has oil rich deposits?

The idea being that they are carbon-rich underlayments that become oil under pressure.

Or, how "soluble" (for lack of a better term) is carbon in Magma. i.e. how can carbon be dealt with in a magma stream other than heat and pressure which results in oil deposits over time?

So, any geologists who can educate me would be appreciated.

This article is beginning to convince me:

https://www.upi.com/Vast-expanse-of-melting-carbon-found-ben...

estimate the amount of carbon trapped in Earth's upper mantle. Scientists suggest there's as much as 100 trillion metric tons of CO2 stored there.*

So based on this data point and the comments from Richard, I think that life is a function much like the sodium-potassium pump, and oil is a function of the subduction plate tectonics which converts carbon to oil over millennia....

We will always have oil. Just how fast can we consume vs. how fast can earth produce. Supply and demand is a. universal constant.

/speculation.

You might enjoy Marooned In Real Time, in which a few humans accidentally persist 50 million years past the seeming annihilation of the rest of the human race.

One of my favorite sci fi stories posited that the civilization was centered on the land that is currently Antarctica and the disaster that destroyed it shifted the earth, moving that continent to the South Pole. Prior to the event, it was a lush South American style landscape.

Maybe we are just looking in the wrong place for our evidence. ;)

If you love fictional settings based on such concepts, check out Numenera [0]: A "hyper sci-fi" set a billion years in the Earth's future, after at least 8 great civilizations have come and gone, leaving the planet covered with the effects and remnants of incomprehensible technology.

Also has a computer RPG [1] by some of the people behind Planescape: Torment.

[0] http://numenera.com

[1] https://www.gog.com/game/torment_tides_of_numenera

We dig up numerous and various animal remains from dozens of millions of years ago. Some are pretty well preserved.

While any particular structure has a very low probability to be preserved in 60M years, some specimens of ubiquitous artificial structures have reasonably good odds of survival. Something like a coke bottle would more likely signal a part industrial civilization.

Hi Peter,

I am giving a talk on my Masters project this week at the University of Hartford. I was doing some background reading a found this thread and your comment! Interestingly the Atlantic published article last year abut a new report (Nature Scientific Reports) that hinges on my Masters work: https://www.theatlantic.com/science/archive/2017/11/the-exti...

We need to have a beer some time and catch up!

I hope it was okay to share your story! It's honestly one of the most inspirational science research stories I know of.

Turning sci-fi into science speaks volumes to your creativity and intellectual capacity to run an idea to ground.

Ants are a good candidate for a second civilization. They live on every continent except Antarctica, they build complex structures, they invented argriculture millions of years before humans did (!), and they live in socially stratified societies. But I guess it ultimately comes down to your definition of what is a civilization.

If we were to find evidence of an industrial civilization before humans we might not even recognize it as evidence, given how different it might be from ours.

> they live in socially stratified societies

This is gross anthropomorphism. Ants don't have societies any more than the cells in our body have societies.

An ant colony is an organism. Each individual ant has just enough neurons to do the one task that ant does. The overall organism is quite capable, true, but it's not intelligent. It doesn't learn novel things, it doesn't purposely invent, it doesn't 'know' anything.

Ants may take over the world some day, but they won't know it.

Can ants form a boltzmann brain?

They basically are one.

Ants pass the mirror test, which is something very few animals are capable of.

Wait really? Do you have a source for this, I'd love to learn more.

No source, but iirc the scientists applied a colored dot on the ants head. When they saw themselves in the mirror the started trying to remove it from their heads.

There are parasitic mites that attach themselves to ants and they look like a colored dot (usually red). I think the ant “thinking” that the dot was a mite is a much more plausible explanation than the that the ant is some how conscious with its cluster of like 3 and a half neurons

So the ant (allegedly -- I'm eagerly awaiting that source!) saw a dot on the ant in the mirror, and tried to remove the dot on its own forehead. The key point: that looks an awful lot like the identification of the self with the reflected image.

The issue you brought up about the mite is a bit orthogonal to this point. I can give you that the ant was concerned about the possibility of having a mite, and the point still remains that the ant thought it was on its own head only on basis of a reflected image of itself. (Compare to the alternative behavior: the ant tries to get the mite off the reflected image, never making any attempt to remove it from itself.)

it was on hn a while back. the link is dead now. https://news.ycombinator.com/item?id=14146776

it’s on wikipedia, with the same dead source https://en.wikipedia.org/wiki/Mirror_test?wprov=sfti1

EDIT: Working link to the paper (in some journal of science): https://www.udocz.com/read/are-ants-capable-of-self-recognit...

http://difusion.ulb.ac.be/vufind/Record/ULB-DIPOT:oai:dipot....

Seems like the point was the mirror caused the response

Bruce Sterling’s story Swarm has a brilliant take on the collective that doesn’t have intelligence. Won’t spoil it by saying more but your comment brought it instantly to mind...

If it doesn't invent / learn novel things, how did it learn the one task that it does today? Where does the leap from nothing to knowledge of that one task come in?

Mutation, genetic drift, gene flow, selection. The forces of evolution.

Oh and lots of time and a huge amount of luck (not even ants can exist on Venus or Mars), but "luck" is just another word for selection bias, or looking backwards in time.

> Where does the leap from nothing to knowledge of that one task come in?

There is no sudden leap, only a huuuuuuuge number of tiny steps and lots of complexity of interactions.

Such absolute statements are a reflection of your personality as much as your world view. I'd take the opposite view of all of this. That your body is a society, and society is an organism. You think the gp is anthropomorphizing. I think you're exhibiting species chauvinism, setting prejudiced goalposts.

You're right actually. There were a lot of absolute statements being made, most of them contrary to what the actual evidence is. Ants pass the mirror test with flying colors -- 30 out of 30 scratched a colored dot off their heads when presented with a mirror, but did not if the dot was the color of their skin. The ants didn't do this when presented with a clear pane of glass with other painted ants behind it. The ants are able to pass the test a few days after birth, but not in infancy.

From what I understand, the current thinking is that the ratio of brain mass to overall body size is much more predictive of intelligence than brain mass by itself. And there are odd cases too in humans like an individual with a severe case of hydrocephaly, with 95% percent of his cranial cavity filled with fluid pushing his brain matter to the sides of his skull, and this individual exhibited very high intelligence and majored in mathematics. There is a lot not known about the brain and animal intelligence, and I would not be surprised if we continue to find out amazing things about ants. I recommend an older book called "Ants at Work" by Deborah Gordon to get an idea of the complexity of ant behavior.

There was a case of a French man who suffered from extreme hydrocephaly. He lived a normal life, despite an IQ of 75, was married with two children, and held a career as a civil servant.

“It is hard for me [to say] exactly the percentage of reduction of the brain, since we did not use software to measure its volume. But visually, it is more than a 50 to 75 per cent reduction,” says Lionel Feuillet, a neurologist at the Mediterranean University in Marseille, France.

https://www.newscientist.com/article/dn12301-man-with-tiny-b...

I think you are fighting a metaphor with another metaphor. Saying that ants form a society indeed implies assigning them human characteristics (anthropomorphism) but saying that they are neurons basically suggests that there are common models to represent an ant colony as well as a neural system. Frankly, I am not sure that the latter approach is more helpful.

Doesn't the fact that ants have already adapted to all kinds of environments suggests that they don't need to evolve civilization (whatever that is) in order to be successful?

Well many millions of years ago there was no Antarctica. Perhaps a civilization came about when there was only one continent, which has happened a few times throughout the earths history.

Why would a civilization even be terrestrial, wouldn't an ocean living civilization be even more likely?

Why does a civilization need to invent agriculture. Perhaps ever evolving hunting technics or even just a sudden massive change in diet could free up enough time for a mass population of a species to start concentrating their efforts on cross societal constructions.

I'm not saying that there was an ancient aquatic civilization of squids that mutated plankton to swim to their mouths. But if we want to ask such an extraordinary question, we must not limit our self in such a way that it makes it easier to deny it.

> Why would a civilization even be terrestrial, wouldn't an ocean living civilization be even more likely?

There's a book about this, can't remember the name right now. Basically it looks at very ancient maps of the Antartica that have details that we only figured out in the 20th century with equipement allowing us to see through the ice layers.

The book posits that there was a rather advanced civilization living before the last glaciation.

It also posits that all the massive flooding mythology found in most human religions is actually stories transmitted by survivors of the previous era.

Barjavel - La Nuit des Temps ?

Funny I just posted about it... the English name is “The Ice people”: https://en.m.wikipedia.org/wiki/The_Ice_People_(Barjavel_nov...

And yes a great sci-fi book, even so the civilization in question is just 900,000 years old not multi millions like the original article.

The book is called "Maps of the Ancient Sea Kings" - Charles H. Hapgood. (1966). Subtitle: Evidence of Advanced Civilization in the Ice Age.

https://www.goodreads.com/book/show/564770.Maps_of_the_Ancie...

Premise of a novel by Clifford D. Simak. Good read.

Ants can also count.

The Hellstrom Chronicle is a 1971 pseudo-documentary about the threat of insects, due to their adaptability and rapid reproduction, to humanity. It won the 1972 Academy Award for Best Documentary Feature. It's available on Netflix DVD and YouTube.

https://en.wikipedia.org/wiki/The_Hellstrom_Chronicle

One strong argument against a civilization in the last 100 million years or so is that our separate continents have clearly been completely isolated, and gone separate evolutionary paths.

If there was a planetary civilization 20 million years ago, there are tons of "invasive species" that would have spread across all continents then rather than in the 1800s. Think rats, sparrows, cockroaches, etc x 1000.

I don't think I have an argument against one back in Pangean times though.

What if it were a civilization of ocean-dwelling creatures?

That would make the whole premise more plausible for a number of reasons.

Arthur C. Clarke and Stephen Baxter briefly touched on this idea in The Light of Other Days.

(Spoiler) The book is primarily concerned with the development of a miniaturized wormhole technology which allows remote viewing anywhere on Earth, and the effects this has on privacy, etc. They discover it can also be used to view backwards in time, and at the end of the book they trace the tree of life backwards towards the universal common ancestor, and discover that it was a microbe seeded deep in a geothermal vent by a civilization of intelligent trilobyte/arthropod like creatures, which knew its own extinction was imminent at the hand of a massive asteroid.

Thank you!! I have been looking for this book in my own sci-fi bookcase a number of times having forgotten both author + title. Got it now :)

This is a great book!

"It’s not often that you write a paper proposing a hypothesis that you don’t support."

We should all do this at least once. What a great practice.

The fact that we found pressurized oil reservoirs ("gusher" oil wells) means that nothing had tapped these cheap and easy sources of energy before.

Or we took it from the lizardmen who put it there for storage :)

Those could have arisen after the last civilization collapsed....beck it could even been are not of their collapse.

Possible counterpoints-- they were much smaller, their minds/values/pursuits were different from ours, they had access to easier & better energy sources for their needs, or they died out due to something unexpected before they got that far.

This reminded me of Dwarf Fortress. Digging greedily and deeply through the Z layers until..

Or that prior civilizations had enough forethought to not even start burning oil for energy.

Or that may be they had some other sources, even cheaper and easier, that we don't know of anymore because they used them all.

Perhaps they tapped to the biggest ones, and developed better tech before they had to get to the smaller ones?

Not just oil, we probably wouldn't have an an iron age without access to unmolested surface deposits.

Iron, tin, copper. If there was a pre-human civilization, they couldn't have gone beyond the stone age, else they'd have consumed the resources our iron age depended on.

The problem with that line of thinking is addresses in the article. The oldest large scale area of "ancient" crust on land is a mere 1.8 million years old (the Negev Desert). The entire surface of the earth is regenerated on a scale of tens of millions of years, any depletion of surface deposits which occured ~100 million years ago would have long since been hidden by the replenishment of new crust provided by plate tectonics.

I don't believe it covers that at all. I believe their definition of crust there is a lot more superficial than it sounds like.

eg, the Chicxulub (Yucutan) crater is 66 million years ago, and clearly hasn't been recycled else we wouldn't be looking at it. We have dinosaur fossils dating ~230-240 million years, so the crust clearly hasn't been recycled that thoroughly. Indeed, the entire Pangea theory would be invisible to us if the continents didn't remain 300+ million years later.

(I'm not saying we should have a fossil record of 'the others', as the article says, there's a survivor bias in fossils. Just that the fossils we do have wouldn't exist if the crust has been geologically renewed in the last few millions of years.)

They're talking about surface markers like roads and buildings. To replace a previous civilization's trashheaps with geological mineral seams, you'd need to pre-date Pangea.

Unless they shipped the metals off planet, that's not really an argument. If anything, an iron using civilization would have made iron more concentrated and easier to find.

Aluminum sure, but iron rusts. In tens of millions of years you could have oxides of iron from a civilization, but no workable steel or iron. Aluminum might survive, gold and platinum would be fine, but not iron. It doesn’t matter though, we’d have gone through many cycles of subduction and renewal in such a long time, so we’d have new surface deposits. Coal and oil would even have started to form over such a long time scale.

What do you mean by "workable steel or iron" ? We're not mining for steel, and it's not like iron age started with finding some magic store of "workable iron" instead of iron oxides - the surface iron and mined iron deposits e.g. hematite, magnetite, etc are oxides of iron. The fully oxidized remains of a scrapyard would form pretty much perfect iron ore.

Our iron (and other metal) mining is not "using iron up", it's just bringing the iron closer to the surface and transforming it in ways that will be undone by millions of years. Fossil fuels are a different case, though.

The majority is hematite, but iron exposed to air will not form hematite, or even magnetite, but hydrated oxides. That iron will also be spread out over large areas in low concentrations, not richly concentrated ores of oxides. It would be economically and energetically unfeasible to gather hydrated oxides from rusted metal and then try to make workable iron from it. It’s certainly possible, but it would be a kind of insane process with low yields.

The other problem is that you need to use coke as a reducing agent, so we’re back to fossile fuels.

Charcoal also work as a reducing agent. The problem with using charcoal is that you're going to be using up a lot of wood to make it.

They'd have to take recycling to a whole new level, to place the different metals separate geological seams, however.

If the human race were wiped out this afternoon, and you came back in 100 million years, you'd still be able to tell the difference between a mineral seam and a landfill or scrap metal merchant.

We're not consuming iron, tin or copper - all the iron, tin and copper that we've brought up from underground is still there. The only difference is that a future civilization might need to look for these metals by smelting rubbishdumpitis and cityruinitis scattered e.g. close to river deltas where our major population centers are located now instead of hematite, magnetite or limonite scattered according to long-term geological processes.

Perhaps they're the result or remains of a previous civilisation? :)

As mentioned above, there's significant churn in the Earth's crust that would shift the location and distribution of resources over very long timescales.

Also, we couldn't be sure that there wouldn't have been ecological or cultural reasons why they just never exploited fossil fuels. Especially if they were ocean-dwelling, it's possible that other methods of generating energy were just much more practical for them to develop first.

They could have discovered fission much sooner.

"nothing had tapped these cheap and easy sources of energy before" ... they were available to tap.

An older period: Carboniferous [0]

Lots of plastic non biodegradable (at the moment): lignin. That's why we have coal, which fueled our Industrial Revolution :)

Ended with the Carboniferous rainforest collapse, caused by climate change.

[0] https://en.wikipedia.org/wiki/Carboniferous

Me: "It would be amazing to go out to the asteroid belt and return a rare-earth metal rich asteroid to solve that problem once and for all."

Other: "That's what the dinosaurs thought."

As the article points out, an ancient industrial civilization would need to mine resources. I think it is fair to say that they would mine a lot of gold and silver for use in electronics. If such a civilization existed then one would think that most of the earth's natural veins of gold and silver would have been mined making large easy to find naturally occurring veins rare. It seems though that our civilization has found plenty of easy to find large scale veins of gold and silver.

Does that not make it unlikely that any ancient industrial civilization lasting centuries could have existed before us? Or over tens of millions of years would more naturally occurring easy to find veins of gold and silver rise to the surface of the Earth's crust?

> Or over tens of millions of years would more naturally occurring easy to find veins of gold and silver rise to the surface of the Earth's crust?

i am not a geologist but, as i understand it, plate tectonics cause a lot of "churn" in the crust. so i think it is certainly conceivable that a civilization could mine all the accessible veins to exhaustion but have many more veins brought up near the surface in the following 60 million years.

Yah, as I wrote my comment I realized that it made sense that there would be churn. I am not a geologist though. It is a fascinating notion. It makes me think of Mote Cook's Numenera http://numenera.com

The nuclear war between the Dinosaurs and the Martian Kangaroos laid waste to both their planets 65 million years ago. The final phase occurred when the Martian forward base on the moon, from where they bombarded the earth, was wiped out by asteroidal bombardment by the dinosaurs. Then the Venusians moved in and finished the job, eliminated all the remaining dinosaurs and the Martian kangaroo people and retreated behind their cloud cover. A few 'roos survived, but retroevolved to a pastoral state. We had better tread with care - lest we anger Venus...

I wish this article had also gone into how long indicators might survive outside of Earth. Could satellites survive? Things on moon or Mars? Might we go to Mars and find some old Mars Rover or underground base or that we left Mars for Earth after we made it uninhabitable?

Edit: typo has -> had

Anything on the surface will be eroded by micometeorites over millions of years. The lunar surface is a layer of dust several meters thick that is the product of that erosion.

Underground artefacts might survive longer, since there is no plate tectonics and little other geological activity, but finding them would be difficult.

We don't even know about previous human civilizations.

Recently discovered Göbekli Tepehttps://en.wikipedia.org/wiki/G%C3%B6bekli_Tepe, the oldest megalith structure, confirmed by radiocarbon tests to be more than 12.000 years old with massive stone pillars and 3d relief stone sculptures mostly still buried is still a mystery to science and some "scientists" still think hunter-gatherers built it with stone chisels.

The interesting thing is that a study based on the drawings on the structure correlated with Younger Dryas period might explain why nothing was found about the ancient civilization that built it.

https://phys.org/news/2017-04-ancient-stone-pillars-clues-co...

https://www.newscientist.com/article/2128512-ancient-carving...

So after all the Atlantis and the flood myth found in most cultures from around the world might be real.

> ...and some "scientists" still think hunter-gatherers built it with stone chisels.

Well yes, that's how actual scientists work: on evidence. Until there's evidence to the contrary, the most likely hypothesis is that the structures were built with the tools and labor that we think humans possessed at the time.

I didn't find anything in your links that mentioned the myth of Atlantis.

> I didn't find anything in your links that mentioned the myth of Atlantis.

Do a YouTube search for Younger Dryas.

You're kidding, right? I'm getting Joe Rogan podcasts, channels like "Atlantis in the Java Sea", "Joe Rogan University" (...). I'm not watching any of that shit. I feel dumber just for knowing that "Joe Rogan University" exists.

Point me towards something that isn't part of the Kook Productions Network please.

> I'm not watching any of that shit.

Even if the best academic papers on the topic are likely to have less obviously incorrect information, you'd probably still learn a lot more by just sitting down and watching all the videos. I haven't seen the Joe Rogan thing that comes up, but I doubt that watching it would magically make you dumber or whatever.

I have to politely disagree. Sure, one video isn't a big deal -- it's just five or ten minutes. But, if I followed up every silly idea presented online with five or ten minutes of watching kooky videos, then yeah, I'd end up less knowledgeable than if I stuck to the stuff that tends to come from better sources.

Also, I've met enough smart people infected by silly ideas to know that nobody is immune to misinformation. Maybe I'm bored and one of those videos leads me down some YouTube rabbit hole that gets me stuck on some nonsense. I'd probably never see it coming; the people who listened to a little too much Coast to Coast surely didn't.

So while I'm excited by new ideas on just about every subject, I also have something of an immune response to them, a conscious decision that I'd rather be uninformed -- and maybe spend that time reading a book or doing something fun outside -- than misinformed. Since I'm not smart enough to know what's right and what's not when I don't know anything about the subject, I rely on the source as a strong signal of trustworthiness.

HN's just about the only guilty pleasure I've got left, but the S:N here is still better than a lot of other places.

I love Joe Rogan, but cringe when he gets into conspiracy theories. He’s so easily mislead cause he just listens to his friends and guests, and rarely does any independent reading or research.

This reminds me of Lovecraft. His mythos was based on the premise that Earth has been inhabited by a series of alien and native civilizations, mostly malign, over the past billion years. Occasionally an artifact or part of a city is thrust to the surface by geologic forces. According to Lovecraft, after humanity falls a race of intelligent beetles will arise.

I think Lovecraft's aliens were more indifferent to humans than malign, or at best slightly annoyed, the way a human might be by a small anthill in their yard. As far as I know, Lovecraft hated the theistic ideal of humanity being the "center of God's creation" and wanted to portray a universe where humans were utterly insignificant and incapable of dealing with the scale of horrors that awaited beyond the safety of the anthill.

My all time favorite theory: http://pbfcomics.com/comics/dinosaur-meteors/

We left some evidence of our existence on the moon so the next civilization will be able to find that even millions of years from now, perhaps.

The American flag is already bleached out. All that is needed is something to remove and disturb the other items left on the surface of the moon, say one or two good asteroid/meteorite strikes We pass across meteorite showers on a constant consistent basis. That evidence wont last 1000 years let alone 60 million

Does LIDAR penetrate dust? I wonder what we might find if we scanned the entire Moon...

We have LIDAR scans of most of the moon.

https://www.nasa.gov/multimedia/imagegallery/image_feature_2...

https://nssdc.gsfc.nasa.gov/planetary/clementine.html

https://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=1994...

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/201200...

Maybe a monolith? ;)

On a side, Hindus believe in 4 Yuga's or phases that go around and round in circles, we are in the fourth one at the moment. Humans exist in all Yuga's and there is then a mahayuga after which there is destruction

After that destruction, the cycle starts all over again. It is the closest thing to evolution formulated by the Indian rishis (scientists of their time). It begins with (on a high level) the water based living beings (fish), amphibians (turtle), mammal (boar), neanderthal (Parashuram), the perfect humans (Ram & Krishna) and so on. It is quite interesting.

Another name for Hinduism is Sanatana Dharma - or the Eternal Way of Life.

> scientists of their time

Please don't masquerade mythologocal saints/yogis as scientists. You are doing a disservice to the accomplishments of real historical figures like Panini, Brahmagupta etc by making statements like this. You don't have to resort to mythological characters to feel good about the supposed glorious past.

I can understand how the tales of Dasavataras can possibly have some allegorical references to evolution but claiming the rishis to be scientists only serves to further ridiculous beliefs like Quantum Mechanics and Relativity originated from Vedas, Rishi scientists developed nuclear weapons in 10000 BC etc.

The main purpose they(Puranas (post-vedic Hindu mythology)) served was to legitimize the Vishnu cult, get rid of the pantheon of older Vedic gods (Indra etc.) and to counter the rise of Buddhism. Most of these stories were made up ad hoc to suit the purposes of their times. I find them quite clever to be honest and fascinating from literary and sociological perspectives.

Take Buddha for example. Once Buddhism and its crusade against animal slaughter / rituals became a hit with the masses and started competing with Brahmanism/Sanatan Dharma/Hinduism, Buddha was made an incarnation of Vishnu and added to the Purana bloatware, while simultaneously obliterating Buddhist monasteries and driving it out of the subcontinent.

Err... source?

A source on ancient mythos not having a basis in science or facts? Or that they served political purposes in their time?

Science has not been able to address every single thing. In fact science is not developed enough to address anything much beyond the most basic things. I'm not trying to disparage science, but I want to emphasize that there is like 99.99% of things we do not know or understand, which is great considering we will all have super interesting times ahead of us. Not a moment of boredom.

> Science has not been able to address every single thing. In fact science is not developed enough to address anything much beyond the most basic things.

Can you be more specific about what things you feel science cannot address? It seems like the one and only proven method for understanding our universe.

> In fact science is not developed enough to address anything much beyond the most basic things.

I mean, we understand relativity well enough to predict astronomical movements and to account for it when synchronizing GPS, we understand biology well enough for genetic engineering and complex medicine, chemistry well enough to create exotic materials and superconductors, quantum mechanics enough to harness it for computation, physics enough to split the atom, space travel, astronomy, etc. We understand a lot more than "the most basic things."

We know much more than the people before us, not the other way around.

Sure. I'll have to dig up the literature but I'd be happy to do so. Can you be more specific ?

If you are interested in investigating, It'd be illuminating to contrast the belief systems in Vedas and Puranas. (Rigveda and Puranas to be more specific. ) If my memory serves right, Narayana(Vishnu) was a minor diety in Rigveda whose only claim to fame was carrying Indra on his back to circumnavigate the universe 108 times. He gradually started gaining more prominence as time passed, as a benevolent and sophisticated alternative to replace the more belligerent/primitive Indra. By mid 15th century(I could be wrong), this process was complete, with Vishnu taking over Indra completely, as established in that Govardhanagiri tale where Indra was utterly humiliated by Krishna.

Coming to the claims on Buddhism, once again, examining the Rigvedic and post Rigvedic belief systems can help you hypothesize how things unravelled. (Replacement of Horse with Cow as the sacred animal, renouncement of non vegetarianism, incorporation of Tantric belief systems etc ) Destruction of Buddhist monasteries and massacring the monks is quite well documented too. Read about Pushyamitra Sunga for example.

Edit: Typos

I can imagine we had very similar conversations & skeptics when the first design for flying machines were proposed. Today we have lost all those scientific advancements made in those times and in time we will re-discover what was already discovered & lost.

I think you are taking an extremely parochial view of things by calling Vedas as "mythology". I believe I do not have to tell you about "Any advanced technology is indistinguishable from magic"... You look at the advanced technology that we unfortunately lost and you think it is magic (mythology in your words). Look around you & think of all the insane (to current humans) & incredible accomplishments of humans that our sciences of today still cannot explain convincingly how they were possible.

By the way, Indra was not a god - god, it was a role, the role of the king of gods. Besides the trimurthis anybody can become Indra. And Buddhism, if you have read it is by far very similar to Hinduism sans the gods concept, but it still embodies the concept of isht-devata by making buddha the preferred god. Both + Jainism are what are known as dharmic gods & have a not of commonality between them that the differences are quite obscure.

Finally, there is no such thing as Brahmanism except in the minds of those who felt threatened by Hinduism & its natural concepts and approach to the betterment of humanity in general. In other words, once you remove Brahmins and Hinduism will cease to exist.

Further, there was never a case of obliterating Buddhist monasteries (by Hindus)! Why would that be if Buddha was an avatara? Again these are narratives that want to paint anything coming out of (ancient) India & hinduism in very bad light. It is mischievous at best, please do not fall for such gimmicks & false narratives & do not feed them. There were some fights between Jains & Buddhists for a very brief time, but with Hinduism it was rarely physical because of the (earlier mentioned) concept of Ishta-devata / polytheism.

> Today we have lost all those scientific advancements made in those times and in time we will re-discover what was already discovered & lost.

Such as?

> Look around you & think of all the insane (to current humans) & incredible accomplishments of humans that our sciences of today still cannot explain convincingly how they were possible.

Examples? I can't tell whether you're referring to ancient constructs (great pyramids, stone henge) or modern engineering (technology, medicine)... the former is uncertainty among multiple plausible theories while the latter is quite well understood (albeit difficult to learn).

> Any advanced technology is indistinguishable from magic

Contingent upon a perspective of ignorance.

Incandescent light bulbs are magic to a medieval society, yet we consider them to be relatively primitive lighting devices. Once the fundamentals are known (electricity) the "trick" becomes obvious and even trivial (resistance makes wire hot, hot wire is bright). Fundamental understanding also allows us to rule out mythical magic.

> Such as?

Let's try gravity on for size. Where's my gravity car? No, really. It would be incorrect (and indicative of a lack of familiarity with modern physics findings) to suggest such technology is limited by power storage or output.

Gravity is just a theory which happens to not fail whatever limited tests we have done so far. I mean everything is a theory for science which is great & how everything should be, except when that theory came from Indian / Hindu rishi's about the consciousness of the universe or any of the studies & accomplishments which got appropriated into Western culture as their own. That is what I am calling out on. Many glaring examples of such dishonest appropriation exist, but we choose to ignore them.

What is a "gravity car"? By my interpretation, all cars depend on gravity in order to move (tire friction).

> Such as?

Both. Pyramids, gravity, Indian temples, stone henge, the patterns in the universe, cells etc. Like one simple example near where I used to live - the architecture of the Konark temple where it had a sort of magnet to levitate the "vigraha". The magnet was at least ~50 tonnes. http://www.thekonark.in/konarkfloatingidol.html

Another temple where the pillar does not even support the temple's roof: https://www.indiatimes.com/culture/travel/this-temple-has-a-...

Musical pillars made of stone. http://www.themysteriousindia.net/singing-pillars-hampi/

You may baulk at these, because your perspective is from probably an arrogant modern scientific outlook, but these buildings & structures predate even the pyramids. Many just too many of these have been destroyed by religious fanatics who cannot tolerate an alternative mode of thought besides Islam & Christianity, so what survives is a sorry remnant of that era, which even so is impressive I think.

> Fundamental understanding

Contingent upon a perspective of ignorance. Is that not correct?

For example, we use light as a form on energy in lasers etc, but only 70 years ago, this would have NOT been a fundamental understanding. The problem is that most of today's people, except the really great people like Einstein, Hawking, Heisenberg, Schroedinger, Tesla etc, try to dismiss (& worse appropriate) any sciences that simply originated in the Indian subcontinent, and I am not sure why that is the case. Why do you think every major civilization in the last 500-600 years wanted to find a path to India. Why do you think the American native people are still called Indians? Why do you think strides in Science & Math were monopolized in the Indian subcontinent & it required the onslaught on the Islamic hordes first and then the European / British hordes to stop the progress of all such advancements? You may not be aware that the industrial revolution of Britain & Europe was funded by India & Indian wealth. Anyways, I digress. My point is that "fundamental understanding" is not limited to a set of people, it just requires time & since India is part of the longest surviving civilization (even the face of 80% destruction) there is a lot of understanding we can acquire from what the rishis had accomplished. We should not throw them all away just because we cannot make head or tail of it...

>>> Today we have lost all those scientific advancements made in those times and in time we will re-discover what was already discovered & lost.

>> Such as?

> Pyramids, gravity, Indian temples, stone henge, the patterns in the universe, cells etc.

So... your claim is that ancient civilizations had more advanced knowledge of patterns in the universe, cells, and gravity? Based on what?

For the other three: it's fair to say ancient civilizations understood how they built the things they built. We have plenty of theories about how they did it, what we lack is evidence to decide between theories. Nothing was "lost", we can recreate those structures today.

> the architecture of the Konark temple where it had a sort of magnet to levitate the "vigraha". The magnet was at least ~50 tonnes.

based on myths. What evidence is there that the myths are accurate?

> Another temple where the pillar does not even support the temple's roof:

Without any pictures of the roof. Have you ever sat on an unbalanced four-legged stool?

> Musical pillars made of stone

Quoting your link: "While during the British era, two of them were cut to check if there was something else producing the sound inside. But they turned out to be hollow" - mystery solved.

> You may baulk at these, because your perspective is from probably an arrogant modern scientific outlook

I refuse the perspective of blind faith. Educated guesses are acceptable when supported by evidence, but stories alone are not evidence.

People say Jesus turned water to wine (myth) - I say doing so would violate multiple fundamental laws of physics and turn the area into a nuclear hellhole (contrarian evidence). If that even happened, he probably just dropped a packet of dried powder in the water by slight of hand (alternate competing hypothesis + Occam's razor).

>> Contingent upon a perspective of ignorance.

> Is that not correct? For example, we use light as a form on energy in lasers etc, but only 70 years ago, this would have NOT been a fundamental understanding.

Correct! And that fundamental understanding lets us separate fantasy from history.

There are Greek myths of heroes "throwing" lighting bolts with the aid of Zeus - now we understand that's not how electricity works, and obviously did not happen verbatim. We can also look back on history and recognize the human tendency to exaggerate for effect.

> Why do you think every major civilization in the last 500-600 years wanted to find a path to India.

Status, military awareness, and aristocratic luxuries (especially spices).

> Why do you think the American native people are still called Indians?

Because Columbus didn't know America was a thing. He sailed west to reach proper India, landed somewhere with brown people, and figured that was India. That label is actually pretty offensive.

> Why do you think strides in Science & Math were monopolized in the Indian subcontinent & it required the onslaught on the Islamic hordes first and then the European / British hordes to stop the progress of all such advancements?

You believe that hilariously Indocentric view of history. I suggest you look up the origin of the word "algorithm" - in truth, all great ancient civilizations contributed to math and science. When one civilization collapsed, it's knowledge was preserved by another.

> You may not be aware that the industrial revolution of Britain & Europe was funded by India & Indian wealth

That's a nice way of phrasing Britain's economic exploitation of her colonies. It almost sounds India had a choice in the matter...

> there is a lot of understanding we can acquire from what the rishis had accomplished. We should not throw them all away just because we cannot make head or tail of it...

Stories survive because they are interesting. They are a great source of inspiration for research that may lead to the truth, but the stories are not truth in and of themselves.

>Please don't masquerade mythologocal saints/yogis as scientists.

What is a scientist?

Does Newton qualify as one in your worldview? He spent about half his life on alchemy.

Will any of our scientists qualify as scientists after a thousand more years of science?

Newton was a mathematician, but he was not a scientist. John Maynard Keynes opined "Newton was not the first of the age of reason, he was the last of the magicians."

"Scientist" is a modern term and I would grant historic figures only that label, if they (disregarding if their conclusions were right or wrong) tried to reason about the world in a systematic fashion and according to empiricism and logic.

Yes, I would tend to agree with you. Science means "application". The origin of science is philosophy. That's why to be a true scientist, one ought to be familiar with philosophy, first. The problem is, in this day and age, while science and technology have developed greatly, philosophy is ancient, and has disappeared.

The evidence is that if you go to the top philosophers these days then they will be unaware of the right answer to the first question in studying philosophy: what is the definition of philosophy? Without having learned it, people have been going around trying to teach what they are unaware of.

The modern idea of a scientist is almost purely an enlightenment-era concept, and only represents one revision towards a better understanding of the world out of many throughout human history.

I think your distinction is pretty arbitrary; in what way does a mathematician not attempt to reason about the world in a systematic fashion and according to empiricism and logic? The only real difference over time has been in our ability to determine valid logic, our rigor in what empirical evidence we'll accept, and our sophistication in how we systematically go about this process. Early philosophers were attempting each of these things to various degrees, they just weren't as good as we are now at them. Really defining the "first scientist" is like defining the "first mammal"; the category is fuzzy and doesn't really mean anything at that level of granularity.

The problem is that the prevalent view of what is considered 'systematic fashion' tends to change rather quickly.

Even in modern science, there is a lot of ambiguity about what scientific method 'permits'. For example, many physicists would scoff at the idea of String Theory being called real physics.

What happens, if, in some 500 years we find a definitive way to simulate experiments? I can see any physical science not validated by such a simulation being dismissed.

Where do Newton’s study and formulations of optics and celestial motion place him in your taxonomy?

I suspect Keynes’s desire to discredit Newton was motivated more by the former’s irrational, perhaps as the first postmodernist, impulse to deny the value of gold.

Newton’s work on optics alone qualify him as a scientist.

And his deduction of the laws of motion, thermodynamics, and gravity establish him as one of the greatest scientists ever.

I should've phrased it better. I meant masquerading fictional scientists as real scientists.

And yes based on my understanding of science, Newton was a scientist and so were the undocumented pioneers who tinkered with what they had available at the time. Be it the wandering ascetics from India who studied the effects of various herbs on humans to compile treatises on medicine like Ayurveda or the priests and traders from Babylonia who arrived at mathematical results based on heuristic principles, in my worldview, they are all scientists.

Take Buddha for example...

An early example of Embrace, Extend, Extinguish?

You spoke my mind. I was just about to compare it with EEE. It has been the modus operandi for the spread of what we now call Hinduism in the Indian subcontinent.

Here is an example of that happening in the 21st century. Classic case of appropriating indigenous dieties.

> It all started in March 2015, when their simple pole-hut shrine for Dokri Burhi (earth goddess) was taken over by a saffron-coloured, tiled, electrified and gated Hindu temple for Kanaka Durga. And in accordance with Brahmin beliefs, all Shudras were barred from it. This is when the local Shudras woke up to the pattern. Almost 150-200 years ago, when a handful of Brahmin families migrated to Ichchapur, they started dislodging the Shudras, who were the original inhabitants, from their ancestral lands. As time passed, Brahmins took control of most of the land, despite the lower castes comprising the majority of the village’s population. In fact, currently, there are 22 Brahmin families in Ichchapur and about 250 odd lower caste households.

https://thewire.in/film/caste-dalit-uprising-in-odisha

Yes, that may be true, because Buddhism for all practical purposes has teachings that are a subset of what Hinduism / Sanatana Dharma is. Some people may not like it because that hurts their sensibilities, especially if they were Buddhists or have a soft corner for Buddhism. So it has been a debate & Buddhism is simply lacking in providing any novel concepts other than what Hinduism already provided. At least the path of Islam / Christianity of "Extinguish" at the point of a sword was not practiced.

No other line of thought has been criticized, marginalized & ridiculed as much as Hinduism has been. Buddhism escaped all that criticism only because of Hinduism being the bigger target. This is also the reason why many people in Western countries resort to Buddhism & not Hinduism when they want inner peace or want to understand meditation. This is going on even now. You'll be amazed at the words used by Christian missionaries, they call Hindu beliefs as evil, the gods as satanic. Muslims? They just try to kill you if you're a Hindu, desecrate & vandalize Hindu temples, forcibly convert young girls through kidnap & rape and worse.. and I am talking of all this happening today, now and will happen tomorrow. Why? Because Hindus are a soft target, they have never harmed anybody. History is evidence to this.

Matter of fact, there is sufficient evidence that Buddhism tried to do exactly that to Hinduism & Jainism "Embrace, Extend & Extinguish" and it was successful in Afghanistan, Kashmir, SE Asia etc, but could not survive in the face is Islamic violence. Look up these regions' history if you do not believe me.

It's fair to call them scientists in the same way you might refer to Pythagoras as a scientist. For most of human civilization religious philosophy and science were not separated.

EDIT: Ah, I see what you meant is that these people didn't exist.

"Ski boots are the worst. Solid plastic. They'll be around till the sun goes supernova."

- Douglas Coupland, Generation X

What if past civilizations exhausted their naturally reachable energy deposits, like we now do with oil, so we can't even guess what did they use as we won't find it on Earth anymore?

There’s a book series by julian may that deals with a time travel device being invented to 6 million years ago where to everyone’s surprise an alien civilization is ruling the planet.

https://en.m.wikipedia.org/wiki/Saga_of_Pliocene_Exile

An underrated sci-fi book based on this premise is Toolmaker Koan by John C. McLoughlin.

Author of "The Helix and the Sword"? Just ordered a copy.

Could something like Fort Knox survive as an unusually concentrated deposit of gold?

On a larger scale, would a city like New York leave an area with an anomalous distribution of elements of a similar nature to what we see where there has been an ancient meteorite impact?

If you look at it in just the right scale: definitely.

The problem is to find the exact spot to look at. Even today, geo-exploration is mostly a joke: drill where experience tells us to. New hotness: Have AI do inference from formalized experience.

There could be a thousand former fort knoxes or NYCs and we, with our methods, only have a snowball's chance in hell to find any.

There are so many open questions out there. For instance, how do we know that the bacteria don't form an intelligent species, too? What if there's something else out there, that just is not intelligence but just like intelligence enables a life form to advance as far as we have and beyond?

Even our understanding of the beginning of the universe is just a model, an idea. It's not like we have proof.

From time to time it's quite important to remember how vast the knowledge is that we don't possess in contrast to the one we do.

A very interesting and difficult part of these kinds of questions is that what we look for has to be very carefully considered. If we look for just what we know now, we might not find the evidence, even if it's there. One of my favorite examples of this is radio waves. Try telling someone in the 1600s about them; it seems unlikely they'd believe you--but yet they've existed forever (?) and e.g. lightning and other natural forces can generate them.

Theres a cool ST Voyager episode about this, the species gets labeled the Saurians. They are extremely powerful and dogmatic, due to living in space for millions of years.

The Mediocrity Principle applied to civilisations would suggest we're not the 'special' first one here. We thought we were special in lots of ways that we've since had to abandon

https://en.wikipedia.org/wiki/Mediocrity_principle

Would be fun to find artifacts on the moon.

I've read about such events and I am a little concerned about their unfolding along with the quickened pace of development in the AI field.

If any artifacts are discovered on the moon, I sure as hell ain't boarding anything called Discovery One, ever.

Surely, we'll leave a few satellites in high orbit, and presumably the raptors would have done as well.

Also, their sitcoms would by now have penetrated a decent bit of intergalactic space, and attracted some attention. Because if it happened twice on this planet, the universe at large would be teeming hi-tech societies.

Or not.

Maybe the apparition of multicellular life is super rare, but once it has happened hi-tech societies are common.

I imagine we’d find a LOT of stone tools before the civilization developed higher tools and then collapsed. Africa is littered with them deep in some areas (due to a million years of humans), and they’re on all continents but Antarctica.

It’s not often that you write a paper proposing a hypothesis that you don’t support.

Come work in corporate IT, we do this all the time :)

Long lasting nuclear waste products could survive for a few million years that may have no natural occurrences.

But there would only be, say 2000 sites of them. Each 10x10 meters in size, buried deep underground. Good luck finding them.

There's no real evidence for this in archeology. We would find little statues of these non humans. we have highly intelligent non humans like dolphins and octopi but they don't have the ability to make fire despite being extremely intelligent, flippers and tentacles are quite limiting.

Read the other posts in this thread. None of that would remain after tens to hundreds of millions of years.

The article asks about detecting an industrial level civilization.

But what about a former civilization which only rose to the level of the Roman Empire lets say? Could we detect that?

There may be a goldilocks period for detecting civilizations:

Too early and they never industrialized at scale, so there's little to detect.

Too late and they became a stage n civilisation and are now the substrate of our universe, so there's nothing to detect.

They Sublimed, Culture-universe style.

What about wicker?

I imagine there to be a whole world of archaeology out there we miss because everything bio-degraded. If you navigated by river and set up a society based on fishing from the river then you might make everything out of wood, with wicker being the material of choice for seats and other furniture.

Such a society could be very sophisticated, as per the people that lived in the Amazon before the white man diseases killed them all for the forest to return to apparently virgin rainforest by the time the white guys got there. So there is your scenario to detect, how would you look out for such a society that had no need for big stone structures?

Rivers used to be clear and full of fish, able to service a river dwelling human culture for as long as there are fish.

If farming happens the river is no longer clear or full of fish, so a recession of sorts hits rather than some big defining event.

Human historical record only goes back ~6,000 years but modern humans have existed for at least ~200,000 years.

We don't have historic records of the stone age, but we do have lots of archaeological evidence. And what we have found are Paleolithic stone tools, temporary camps, and some permanent settlements around 12,000 years ago. Nothing close to anything resembling the Roman Empire.

Would our roads would survive? Never before has humanity so dramatically changed the planet in such a fundamental way. Roads from older civilizations like the Romans and the Sumerians would probably erode, but our modern asphalt is pretty insane when you think about it.

If left on the surface for millions of years, yes they would fade to nothing. But in many locations, they'd get buried in layers of swamp and sediment. Even if they shifted around via plate tectonics, many of our modern highway junctions are quite massive. With 7 billion people and the insane amount of infrastructure on our planet, surely some of that would survive if a future civilization started digging a few hundred meters through bedrock.

How long before roads churned under the pressure of the earth into indistinguishable small pieces of rock? Would they be gone in less than a million years?

As a side note, this makes me think about all the world that goes into nuclear waste burial sites, and how we're currently trying to create warnings that may need to outlast our civilization by millions of years.

Anything made of concrete would probably be gone in less than 1K years. Even granite slabs don't last very long...

What about the Colosseum? The Pyramids are also in quite good condition. And the ruins of Gobekli Tepe are more than 10k years old.

It seems to me that commenters in this thread keep taking the durability of materials under average conditions as a measure of what traces would be left after millions of years. By the same standards, we shouldn't have a single bone or trace that anything that lived more than a few hundred years ago. However, when there is a very large amounts of specimens, some happen to be preserved in exceptional conditions or undergo transformations which let them survive or leave traces, direct or indirect, for tens or even hundreds of millions of years.

How long before roads churned under the pressure of the earth into indistinguishable small pieces of rock? Would they be gone in less than a million years?

When built on top of freezing and thawing soil the current roads and asphalt start crumbling away already in few years only.

The lizards...and some say they still are with us! /s https://en.wikipedia.org/wiki/Triune_brain

Betteridge's Law says no. But it's fun to think about.

Heh, this is a rare situation where this doesn't apply. The point to the leading question in the title is clearly not to refute it, it's to point out the idea that we can't refute it as well as everyone expects.

The point is more "Yeah, there's no evidence for this. But if there was, it would be very easy to miss."

> Heh, this is a rare situation where this doesn't apply.

The law states, "Any headline that ends in a question mark can be answered by the word no."

Presumably you're a believer in the lizardmen.

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