We've talked about the big five extinction events, but of those 5, the big one was the Permian extinction. So let's talk about that now. The Permian extinction, sometimes people refer to it as the great dying. Now I just include that for illustrative purposes. Right?
If you're alive at a time called the great dying, it's a bad time to be alive. Now this happens about 252,000,000 years ago at the end of the Permian. Now the Permian is the end of the Paleozoic Era. The Paleozoic goes from the Cambrian to the Permian, and after the Permian starts the Mesozoic. You can sort of think of that as the time of dinosaurs.
Alright. So what was life like on earth at this time? Well, we had reptiles, sort of proper reptiles that you would recognize as reptiles running around. There weren't dinosaurs yet and there weren't birds yet, but there were reptiles. Now there were no mammals, but there were mammal ancestors, the ancestors of mammals sort of had their own branch on the tree of life at this point.
And, well, there were fish, sort of proper bony fish that you would recognize as relatively modern looking fish swimming the oceans. There were land plants. Now there weren't flowering plants yet, but there were ferns and conifers living everywhere, and there are all sorts of insects running around. Now right now the earth just has one super continent, and that continent we call Pangaea. So all life on land lives on Pangaea, and really all life in the ocean most life in the ocean lives in the shallows.
So most of that life is living sort of around the coasts of Pangaea. Alright. So this Permian extinction, we're gonna say that about 96% of marine species were wiped out. That's a lot. Right?
96%, almost all of them, and about 70% of terrestrial species. Right. So what happened? Well, again, sort of illustrative name here, the world went to hell hypothesis. Well, this is the idea that there was just this massive volcanic activity.
And this volcanic activity, which we've illustrated right here, right, it's gonna have lava flows in what we now call Siberia that were hundreds of meters thick. So at least that part of the world's pretty inhospitable life. But from these volcanoes, it's just releasing so much gas that it really changes the chemistry of the Earth. It's gonna increase CO2 levels so much that you're gonna get a 6 degrees Celsius rise in atmospheric temperature, which we've sort of illustrated up there. Right?
This massive global warming, 6 degrees Celsius is about 11 degrees Fahrenheit. That's massive global warming, and if that happens relatively quickly, it would be very hard for organisms to adapt to that sort of temperature change. Now we're gonna have acid rain, and acid rain is gonna kill the plants. And if the plants are dying, well, the things that eat the plants, they're also gonna have a hard time. Right?
Now from the CO2, other gases, you're also getting acidification of the oceans that we see there. And from all these things dying, you're having all these bacteria growing up as decomposers, and those are gonna lower oxygen levels. Oxygen levels in the ocean are gonna drop. So in the oceans, if the oceans acidify and you're losing lots of oxygen, it's hard to stay alive, and that's why most things didn't. Right?
So, again, 96% of marine species going extinct, 70% of terrestrial species. That means if a species is alive at this time, it's likely it wasn't afterwards. And what is able to survive, that's gonna have a huge impact on, well, how life develops going forward. Alright. We're going to look at more extinction events coming up.
I'd say it's going to be fun, but there will be lots of death.