LoL that is a cool idea, and probably would mean the universe is even older than we thought.

If that were true, we'd have some evidence of it. As it is, we don't. I'm inclined to follow the null hypothesis until there's some evidence that suggests it's worth considering.

I can only worry about the only I can honestly care about... Mine. Will I have time to hug my love ones one more time? The flooding and noah and the big boat and all that crap... not of my interest... the nuclear wars in Mesopotamia... don't give a flying mayan astronaut. I am in this one. The one I was born and will die in. With all the pain and glory. They say we may only know 6% of our history and that is a lot to learn. I don't believe the hype. Hear Say. Lies been around since the first time the Erectus came down a tree and found a cave.

I would say the Indians started in America. They were as modern as they could be in their land.There's not many left. We took over their home land. They have more right to protest then others seeing how we took thier land from them. It's no different then the christian kings invading other countries in the name of god.

I tend to doubt if there ever was an earlier civilization because we can for life on earth way before the dinosaur extinction. Prior to the earliest life we know the earth was a burning rock.

Unless there is evidence, facts and data to support anything, it is just speculative talking points. (IMHO)

Aaah no..civilizations/ cultures rise and fall..some are buried by sand, some are lost due to subsumption by a more dominant culture.
Human's are a product of evolution at a specific time and place...that confluence is not going to happen again.

Given an infinite amount of time and an infinite number of universes, I guess anything is possible.

Watch a speculatory show like Ancient Aliens. They cover a lot of things like that especially on shows where they cover Atlantis or Mohenjo-Daro.

Puma Punku is an excellent example of a totally unknown society. If it ended in Hiroshima/Nagasaki-like blasts that razed Everything, then erosion... not everything that exist is on the current surface of the planet, either.

Octopi may actually be survivors from one of those ancient civilizations

Well, if we are talking about a human, or close to human, civilization, that limits it to about a million years or so ago at most. And such a civilization would have left a host of artifactd even after a million years, gold lasts forever. There would also be unmistakable layers of pollution (including radioactive pollution) in things like icecap, ocean sediment, and lake sediment cores. Scientists who study such things would have noticed. The utter absence of any such evidence effectively rules it out.

If we are talking about something pre-human, say intelligent dinosaurs, well, still major problems. There is no evidence anything evolving that was approaching human cranial capacity. And no other evidence. The only way you could make such a case would be several layers of special pleading. Say, something evolved very quickly geologically speaking, their civilzation was limited to the Yucatan penninsula, and all trace of it was wiped out by the Chicxulub impactor 66 million years ago. And even then the geologic boundary at that age has been extensively studied, so their civilization would of had to be remarkably free of anything that would have made pollution.

So, interesting thought experiment, but all leads to the same conclusion: Unlikely to the point where it can be ruled out.

Many civilizations have come and gone, but I doubt that any of them were as advanced technologically or knowledge-wise as today's.

You've heard how the Earth's axis/poles rotate 90 degrees every 50,000 years or so?

At one time Antarctica was on the equator-ish.

the cataclysm that would destroy virtually all semblance of their society. Imagine our world now with Out cel phones. people would become paralyzed.

Read A Canticle for Leibowitz

As fascinating as that is, there is more evidence against, than for the idea.

Not a plausible scenario. There is no evidence where there certainly should be at least a little and probably plenty. We have a reasonably good record of conditions on this planet going back millions of years and reliable models of conditions prior to our ability to extract physical evidence that indicate that once life got its first foothold about 3.8 billion years ago, there has been a steady, slow progression since. The Earth itself is but 4.5+ billion years old.

If alien archaeologists come to Earth two billion years from now, they would find ample evidence of our existence. It would be obvious that we had been here and there would likely be enough to form a fairly accurate picture of who and what and how we were. We don't see anything like that in the record. This is one of the reasons why the ancient aliens nonsense is so easy to debunk. That is not to say we haven't been visited by an alien species at some time in the past, but the likelihood is about as good as there being gods and unicorns.

No real evidence for it and no reason to think it is true. There is more evidence of ghosts (about a million eye witness reports across history, the planet, and cultures) just to give you an idea of scale.

I don't believe in ghosts but as it stands right now there is more evidence for ghosts compared to evidence of an tech advanced human culture that we know nothing about.

There is evidence of ancient civilization - ruins, art, records, graves, human-caused evvironmental change (deforestation for farming, and so on), etc.

There is evidence of millions of years of life - fossils, dna records.

So if there was a former 'intelligent life' that disappeared, don't you think there would be SOME evidence? Somewhere?

It seems unlikely that a civilisation as advanced and extensive as ours has existed before - imagine how much evidence of modern western society will be left in, say, 20,000 years, or even ten times that. Assuming we're talking about a human civilisation, which I assume we are as there doesn't seem to be much chance of there ever having been a super-intelligent species of dinosaur or trilobite capable of building a civilisation, humans simply haven't been around long enough to have created a civilisation of this type and for all traces of it to have vanished.

However, other civilisations have existed and disappeared - Ancient Egypt, Sumer, Mohenjo-daro and more, which in some cases were very advanced indeed - Mohenjo-daro, with its city planning, flushing toilets and sewage system, could be considered comparable to 19th Century London - in fact its sewage system was better than many cities of today.

They all fell, and in time ours will too; due to war, plague, environmental destruction or some other cataclysm such as an asteroid strike.