On 16th April NASA scientist Gavin Schidt alongside Adam Frank published a speculative paper questioning whether an advanced industrial civilization could’ve existed on Earth before mankind, likely to the delight of clickbait websites and tinfoil hat enthusiasts everywhere.
Entintled “The Silurian Hypothesis” after the reptilian race that inhabited the Earth during the Silurian Epoch (443-419 mya) in Doctor Who, Schmidt and Frank ask whether evidence industrial civilizations (i.e. civilizations with “the ability to harness external energy sources at global scales”) could be detectable in the geological record.
Naturally, such a question is bound to raise a few eyebrows, so did they actually find evidence of such a civilization?
Of course they didn’t! Schmidt and Frank themselves state that it is highly unlikely that an advanced, industrial civilization akin to our own existed before us, and even if it did the fossil record is notoriously incomplete. And despite the paper’s title, there was almost certainly no civilization during the Silurian epoch (a claim Schmidt and Frank themselves explicitly disavowed).
Eurypterus, a common Upper Silurian eurypterid. Dimitris Siskopoulos from Alexandroupolis, Greece [CC BY-SA 2.0] via Wikimedia Commons.
But in many ways that wasn’t entirely the point. In writing this paper, Schmidt and Frank never sought to prove the existence of past civilisations so much as they sought to establish potential parameters by which we might hypothetically find evidence of their presence, such as carbon dioxide and methane levels in the geological record, as well as mass extinction patterns.
Additionally, by using the current Anthropocene era as a point of comparison, Schmidt and Frank raise important questions about the long-term impact of our species on the planet, an impact which might still be evident millions of years after our passing.
Nevertheless, it’s easy to see why the Silurian Hypothesis has garnered attention. Though the question it poses might be scientifically unorthodox, the idea of precursor civilisations is a pretty well established fictional trope.
H.P. Lovecraft in particular predicates many of his eldritch tales on ancient civilizations lost to time. This is most evident in At the Mountains of Madness, which centres on one such civilization that lived for millions of years in Antarctica before being overthrown by their monstrous slaves, the Shoggoths. Leaving Lovecraft’s characteristic racist subtext aside, I think the reason why his work and the Silurian hypothesis are so fascinating is that they remind us of just what a small space we occupy within the vastness of time.
So next time you’re putting the bins out, think about the legacy you’re leaving. After all, your household waste might just become a scientific curiosity for the Earwig people who will inevitably inherit the Earth after the collapse of our decadent species.