[BuyMyBitcoins]

I figure that any industrialized civilization would have left indirect evidence of itself by mucking up the fossil record with introduced species. We intentionally and unintentionally introduce plants and animals far outside their natural range.

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

You would see some species inexplicably take on a worldwide distribution, or see species suddenly turn up on far away landmasses with no good explanation.

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

The link above is fascinating, but I do not think it is evidence of any past civilization. This probably happened naturally, but it does seem exceedingly rare. If there were a past industrial civilization there would probably be tens of thousands of examples like this one.

[naasking]

How many introduced species are there as a percentage of all existing species? This seems like an important number to calculate the probability that we might have missed such an introduced species given the fossil record we have.

It could also be that introduced species are less likely to be found in the fossil record for whatever reason.

Then again, maybe we have found such a thing but haven't recognized it for what it is due to missing context.

[BuyMyBitcoins]

That’s a good point, and I don’t have an answer. In my mind I was thinking of more obvious examples, like camels being introduced to Australia. Or cichlids from Lake Victoria being introduced into isolated lakes in North America. The idea being that you would notice some very obvious out-of-place fossils.

I also assume that these species, often invasive, would outlast the civilizations that introduced them. So you could probably also infer some of this by looking at descendant populations.

[naasking]

We would naturally just assume that the same species appearing in different places just implied that those places were closer together in the past + migration. And so we have Pangaea before continental drift.

If we lacked progenitors of those species in some places, we would just call it a temporary gap in the fossil record, of which we have many.

We're pretty good at inventing explanations. Eventually these gaps might start looking conspicuous, but I'm not sure if we're at that point yet.

[melagonster]

but we have good prove of continental drift now. before we getting enough evidences, this theory just a joke.

[naasking]

You've missed the point, because these theories are basically compatible with the existing evidence, they just tell a different story.

[BuyMyBitcoins]

I suppose a counter example would be a species found on multiple continents but during a time when they weren’t joined together. But you’re right that a natural overlap due to past plate tectonics could lead to false negatives with what I’m suggesting.

[inglor_cz]

"are there as a percentage of all existing species"

Percentage of total biomass is more interesting. The more (and bigger) bodies, the higher the likelihood of being fossilized.

[SubiculumCode]

Interesting thought. However, one of the ideas that the article brings up is the extreme undersampling problem of fossil records. Its conceivable that a 300 year blip->catastrophe would be missed entirely in the fossil record.

[tetris11]

> You would see some species inexplicably take on a worldwide distribution

Im reaching here, but: https://en.wikipedia.org/wiki/Cat_gap

[redandblack]

Obligatory Pratchett reference - https://en.wikipedia.org/wiki/Strata_(novel)

[greatfilter250]

> worldwide distribution

Why does an industrial civilization need to be global?

Our industrial civilization appeared extremely quickly, perhaps in the past 300 years, but it happened to appear within a preexisting global trade and travel network. An industrial civilization which existed for a few hundred years, outside the context of such a network, might not ever see the need for one.

[Nasrudith]

Industrialization would increase demand for raw materials and heavily encourage expansion even if not required per se. Self-sufficiency of a single area becomes more difficult as technological complexity rises as well. Let alone demand for the "exotic" materials like rubber or even bronzemaking needing tin for their copper or visa versa. (The two seldom occur within different geologies seldom close to one another.)

[inglor_cz]

If the beings that created it were capable of living across the globe, and not limited, say, to the equatorial region, it is somewhat likely that such civilization would diffuse much like human industrial civilization did; older, less efficient societal structures would be unable to compete with it.