It’s pretty coincidental that last week for Sorta Random Sunday, I wrote about an idea that got stirred from listening to an episode of the podcast, Stuff You Should Know. And on the day that post published, last Sunday, I just so happened to be listening to another episode of the same podcast that I found so interesting that it is becoming a post itself! But this one is a bit more out there…about something called the Silurian Hypothesis.
What is the Silurian Hypothesis?
In simple terms, the Silurian Hypothesis asserts that humans may not be the first intelligent life forms on Earth. And that if we were predated by another form of intelligent, industrial life, pretty much all signs of them would be erased by now.
Whhhhhatttt?
Yup, that’s what it says. And it’s actually based on some pretty good science.
But what about dinosaur fossils?
This would seem to be the first piece of evidence most people (including me) would point to in order to discredit this theory. If there was some other intelligent civilization in the past, why haven’t we found their fossils?
Well, to start, dinosaurs existed for over 150 million years. That’s a very long time. And, despite being around for that long, we have found remarkably few dinosaur fossils. As an example, for all of the T. rex dinosaurs that ever existed, only 50 fossils have ever been excavated. That’s remarkably few.
Moreover, humans have only ever existed for a very short period of Earth’s history, 100,000 years.
If some other intelligent industrialized society existed for the same micro fraction as us in the past, the chance of finding evidence of that would be exceedingly small.
So maybe we weren’t the first ones here?
How did the Silurian Hypothesis come to be?
It all started as a conversation between two colleagues, Dr. Adam Frank, an astrophysicist, and Dr. Gavin Schmidt, a climatologist. Cool enough, Dr. Frank is a professor at the University of Rochester, where I did medical school.
Anyway, Dr. Frank had interest in examining far away worlds for evidence of previous intelligent life. After all, while we look to the skies for present alien life, we may actually have missed it or still pre-date it.
Well, Dr. Schmidt blew Frank’s mind by suggesting that we might not have to look to other galaxies for this hypothesis. It might have happened on Earth.
Then they named it the Silurian Hypothesis after a race of intelligent lizard people from the show, Dr. Who, who moved and lived underground only to emerge at a later date (I have never seen Dr. Who so if any other that is not 100% correct, please forgive me).
What would we look for to test this theory?
The real idea behind this whole thing is that intelligent life would leave signs behind, structurally, geologically, and archeologically. Then, future sleuths like ourselves would be able to find them.
Of course, we already spoke about fossils. But really the fact that fossils happen at all is a miracle. It takes incredible circumstance for them to form in the first place. And there are a multitude of forces, including simple earthworms, degrading them at all times.
In terms of structures, erosion and corrosion are constantly working to degrade them. Did you know that without maintenance the average NYC skyscraper would become rubble in just 50 years? Structures won’t outlive us or any other sentient species for very long.
However, there would be signs. One of the most speculated of them are changes in carbon dioxide emissions into the atmosphere – scientists measure this using ice cores. For instance, that would certainly be an indicator of our past existence to future beings. That and microplastics.
Funny enough, a burst like this has happened in the past. 56 million years ago, the planet went through something called the Paleocene-Eocene Thermal Maximum (PETM). Carbon levels rose so much in this time that average ocean temperatures in the Arctic increased to 70 degrees F!
So, is this evidence of prior intelligent life?
Do we actually believe the Silurian Hypothesis?
No. We don’t. And neither do the authors of the original scientific work, Drs. Frank and Schmidt.
Take the PETM we just discussed. Those changes in carbon levels happened over hundreds of thousands of years. But…the changes happening now occurred over just 300 years.
And that is the rub of this whole thought experiment. That while we may not believe this hypothesis is what actually happened, it does demonstrate that there would be evidence of past intelligent civilization.
And we can look for those clues on other planets, like Mars. More over, we can use this to think about the imprint, good and bad, that we are leaving on our planet now.
Plus it’s pretty fun to think about…
And if this kind of thing doesn’t float your boat, here are some helpful posts guaranteed to improve your financial well-being:
- How Much Is Enough Retirement Savings?
- Physician Side Gigs to Make You Passive Money
- Building Your Investment Waterfall as a Physician
What do you think? Could previous intelligent industrialized life exist on Earth? How would we know? Let me know in the comments below!
