Approximately 250 million years go the Earth went through a massive, fundamental change, bigger than the extinction of the dinosaurs, and yet most of us are completely unaware that this event ever happened. What am I talking about? The Permian Mass Extinction, the end to al life on Earth.
There is no denying the fact that the extinction of the dinosaurs massively altered the world that we live in. Not only were dinosaurs wiped off the face of the Earth, experts estimate that approximately 75% of all organisms ceased to exist in what would come to be known as one of the ‘worst mass extinctions’ in the history of the planet.
What many people don’t realize is that this wasn’t the largest mass extinction that this planet experienced. Up to this point, little has been known about the Permian Mass Extinction, except that it is predicted to have killed off 90% of the species on earth, including 95% of marine life and 70% of land animals. It was devastating, to say the least. Also referred to as the ‘Great Dying’, it wasn’t a one-day sudden event but rather an ongoing situation that is estimated to have lasted millions of years.
The one piece of the puzzle that has stumped scientists up to this point is the actual cause of the mass extinction. What was it that actually nearly wiped out life entirely? It’s a topic that geoscientists have dedicated great time, effort and funding towards, believing that an understanding of this event could provide us with key information to protect our planet as we move forward.
A team of researchers may have finally discovered the truth…
In order to understand exactly what happened at that point in history, the team collected and analyzed a series of Siberian rocks. These rocks were specifically selected as they dated back to the time of extinction, meaning that they would contain any significant atmospheric chemicals at that time.
The study revealed that the Earth’s atmosphere was fundamentally altered during the extinction, flooded with a number of deadly chemicals that depleted the ozone layer. In doing so, the planet no longer possessed the necessary conditions for most organisms to survive. This included bromine, iodine, and chlorine.
“We concluded that the large reservoir of halogens that was stored in the Siberian lithosphere was sent into the earth’s atmosphere during the volcanic explosion,” the study’s lead author Michael Broadley explained, “effectively destroying the ozone layer at the time and contributing to the mass extinction.”
In short, a massive volcanic eruption released these chemicals into our atmosphere, the precipitating event. This demonstrates just how important the ozone layer is to our survival, as well as how quickly it’s protection can be stripped away. Will this new discovery impact the way that we look at life on Earth today?
Image via Scientific American