[dash2]

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

[graemep]

If whole populations were wiped out and the world was repopulated by a small remnant would that not account for it? Or if an extinct human species had an advanced civilisation?

[AlotOfReading]

The founder effect differs between small populations filtered from a large population vs a smaller parent population.

I want to point out that the silurian hypothesis is specifically about civilizations removed from us by geologic time. Advanced human precursor civilizations are much more effectively ruled out by the current evidence. Basically, a hypothetical precursor society either has to look very different from any we know about and materialize out of nowhere like alien colonists, or they didn't exist.

For example, we know they weren't using large amounts of fire because nothing in the global charcoal records points to that. We know they weren't using plants that produce pollen because we don't find phytoliths with domestication indicators. We know they weren't using surface metals, because there was lots of that still around when the classically ancient civilizations started. We know they didn't contribute significantly to the gene pool. We have no material culture from them. We don't have a location on Earth they would have lived in. Etc.

[cwmoore]

“Basically, a hypothetical precursor society . . . has to materialize out of nowhere like alien colonists, or they didn't exist.”

Proof aliens exist—thermodynamics, no materialization out of nowhere.

There are layers ;)

[simonh]

There’s always the hollow earth!

[sgt101]

My thoughts:

Civilisation implies large scale agriculture.

Large scale agriculture implies specific pollen signatures.

We don't see any of these signatures in the pollen records dredged up from lakes and seas.

There was no previous civilisation in the last 1.4m years (this is the depth of the pollen records we have I think).

[saidnooneever]

it could essentially be much longer ago, but you are right and imho this is strongest evidence. civilizations dont need to evolve to high technology to be a relatively advanced civilization and say, build pyramids. but they do need plenty of food structurally available in any larger numbers than 'big tribe'

[gregdaniels421]

The proper Silurian period had no pollen, so that wouldn't make any sense.

[MrDrMcCoy]

Or it stayed concentrated for a long time until local conditions forced a scattering.

[throw1234567891]

No. That’s exactly how we know.

[simonh]

I know, let’s modify our DNA so if we’re wiped out nobody will ever know we existed!

[saidnooneever]

they could be distinctly different dna, wiped out and evolved again from scratch.

[rubylimetea]

> I can't speak to dinosaur people

Dash out of context