Just a couple of points, we’re assuming that any previous civilisation would be at the same level as our own and of the same kind where it comes to material goods.
Also we’re still discovering things about our planet that would have been considered totally incredible even a few years ago.
Life around Smokers, extromophiles generally and even things like tectonic plates etc.
Just because we haven’t found any signs of Dinosaurial civilisation so far doesn’t mean we wont because of having exhausted all possibilities of detection.
Sure, but I highly doubt the number is anywhere near as high as a 10th of a percent.
Fortunately, it doesn’t have to be anywhere near that high; given the numerical arguments that others have posted, even if, say, 1 in a billion survive, that’s probably enough to leave behind sufficient evidence that we couldn’t be ignored.
But the question remains whether it’s even as high as 1 in a billion.
Glass degrades fast, at least the glass I’ve dug up on archaeological excavations. Bottle and window glass typically iridizises, delaminates and gets crumbly in just a couple hundred years in the ground. Our acidic soil might have something to do with this, though.
In a related vein to the OP, how likely would we be, as a society, to accept an apparently credible, though highly fantastical fossil find? Here’s the scenario:
A paleontological team, well-regarded in the scientific community, finds a single impression cast type fossil, highly detailed (like this trilobite), which they date late-Jurassic. They’ve faithfully recorded extraction of the artifact, including photos and video, from stone strata that has been dated meticulously for accuracy. The fossil appears unambiguously to be that of a large coin, with detailed impression of both sides: obverseand reverse.
Both sides show a series of unknown symbols (not the English words I put on, of course…most assuredly not the BC date :D), encircling graphical representations a of large-craniumed Tryannosaurid with what looks like an opposable thumb on the reverse view. A few Tyrannosaurid fossilized bones are found in close proximity to the impression cast, but no skulls or extremities are found. No other artifacts suggesting Jurassic-era technology are found…anywhere.
The paleontologists publish their find in peer-reviewed journals and make rounds with the lay press. They submit to and pass polygraph testing. After the buzz dies down, they recluse themselves from public scrutiny and return to their scientific pursuits, doing nothing to suggest charlatanism.
Questions: Would the fossil be taken at face value, attributable to a technologically advanced brainy dinosaur (by the lay public, their peers, both)? Would the paleontologists be regarded as hoodwinkers, despite their solid credentials, meticulous records and passing of public scrutiny? Would the artifact be attributed to an incredibly improbable natural occurrence, instead of the highly fantastical artificial origin? If no other similar finds are made, would opinion change after a year, or five? Would reference to it be made in textbooks after 10 years and beyond?
I’d say it would depend on if it was a one off find or if there were other indications of a technical society in the Jurassic. If it was a one off find then it would all hinge on the chain of evidence, how it was found, how it was documented, the dating analysis, etc etc. If those were good, then it would be an indication of something, but my guess is that a lot of the scientific community would initially dismiss it as a hoax or at least remain highly skeptical.
Some percentage would be intrigued, though, and if they started to find other similar things then that skepticism and outright disbelief would eventually fade. Science is a wonderful thing, after all.
Why? That would be less than 1 in a billion odds, depending on what your initial assumption was wrt the total number of artifacts. Why do you think that it would be no where near as high?
Well, that’s pure speculation. I’ve seen the figure of ‘the odds of a dinosaur becoming a fossil is 1 in a million’ tossed about before, but doing probability like this entails a lot of assumptions that can wildly change the results. I tossed out the 1 in a billion simply to illustrate that even at those sorts of ridiculous odds there would still be a substantial (millions if not billions) of potential artifacts to find, given a civilization that was comparable to our own for the last 40k years. Even if you made the odds 1 in 10 billion or, possible (depending on what your initial assumptions were) 1 in 100 billion there would still be a lot of potential artifacts or at least data that could be discovered.
It’s all going to hinge on what assumptions you want to make as to determining if the 1 in a billion is high (which I think it is) or low, and how you want to justify your assumption (i.e. what you are basing it on).
Assuming your WANumbers are correct, then what ? One archeologist has the amazing luck to find the one inox fork that hasn’t rusted away, in the one peat bog, because that one landslide uncovered it. Presumably, there are about a million of those still available around the globe - but they’re all under kilometers of rock, soil and silt now. Just finding that one was already a one in a billion shot.
What does it say, and what does it mean ? Do you really figure they’re going to picture the fastuous excesses of the current human condition from a barely recognizable rusted hunk of metal ? Which they might not even figure was a fashioned tool (as opposed to, say, the one time result of a lightning strike) if they’re not *exactly *like us ?
Hell, even if inox forks or plastic six-pack rings become our civilization’s stone arrow heads (i.e. findable almost everywhere if you’ve got a good eye), it’s not like they’d provide archeologists with much to work with to identify us, what we’re like, what we do, what we’ve achieved. Or what killed us off.
Even now, figuring out “ancient” societies barely 5000 years old, which we know for sure were human and which have left plenty of artifacts yet little in the ways of written records is pretty difficult to say the least…
Say I went off and carved a completely manmade “fossil” that was made of the exact same material as a natural fossil and then I placed it right alongside a 5M year old natural fossil, in 145M years time, is there going to be some magic process that causes my artificial fossil to be destroyed but the natural one to be dug up by archeologists?
The point is, we’re dropping a ton of these manmade “fossils” everywhere. Yes, the typical glass bottle may only last 1 or 2 million years but so will the typical fossil. The only fossils we’re discovering now are the exceptional ones and the same will apply to glass bottles. Except we’re leave a lot more glass bottles than most animals left fossils.
I’m not saying there’s anything magical about the number 1 billion; I obviously pulled that out of my ass.
The point is just that there’s some large number that we’d have to beat to leave recognizable traces–and, while I don’t know that number, I’m sure 10000 isn’t anywhere close to it.
If forks have a 1 in a billion chance of surviving, and we’ve only landfilled 1 billion forks, then you’re right, they’ll probably discover 1, or a handful at best, and it’ll be hard to prove that they’re an artifact of civilization. But there are many things that we make in the trillions; if any of those artifacts has a 1 in a billion chance of surviving mostly intact, then archaeologists will probably discover them left and right (and date them all to a tiny range of time 150M years ago), which is enough for people to realize something is up.
So, the question is, do any of these artifacts that we make in the trillions have even a 1 in a billion chance of surviving? (And of course you can adjust both of those numbers in tandem for different kinds of artifacts.) If so, there will be evidence of our existence; if not, there won’t.
Now you’re moving the bar.
The OP, and most of the subsequent discussion, is about whether there would be geological evidence of a civilization. It doesn’t take nearly as much to say, “Someone must have been machining stuff” as it does to figure out our table manners. 1000 forks will tell you the former, but it won’t tell you the latter. But that’s fine; the former is the question we’re trying to answer.
I’m guessing the vast majority of even stone arrowheads will be rendered unidentifiable after 150-million years, via affects of normal geophysical forces on rock over large time-frames. Though ubiquitous today, they may not remain in critical enough numbers to favor odds of discovery in the future.
Even if your artificial fossil has the same chance of survival as the natural fossil, it’s still a numbers game. You’re comparing an arbitrary artificial fossil to a natural fossil that has been dug up—one, therefore, that is a “winner” against very great odds. Not only do natural fossils have to overcome great odds to become fossils, once formed, they have to overcome probably greater odds to resist geophysical force decomposition (not sure if that’s the correct term) and remain intact fossils…coupled with the great odds of being discovered. To level the playing field you need to compare the artificial fossil with a natural fossil that has successfully formed, but has yet to remain in the Earth for 150-million years.
