When all the continents were smooshed together into Pangea, was the interior of the super-continent largely desert?
Wouldn’t the moisture in winds coming off the oceans fall as precipitation long before the wind reached the centre of the continent?
And a follow-up: would there have been much life in the oceans on the other side of the world, without continental shelves or coastal areas?
There’s a lot of fossil evidence that indicates it wasn’t all desert. In fact, the fossil evidence is what helps to prove that Pangea was all one big continent. You have fossils of identical species found in areas all across the existing continents in a way that only makes sense if these plants and animals were able to easily get from one area to another (i.e. they were all connected). It’s fairly clear that Pangea wasn’t a big desert wasteland.
That said, Pangea formed about 300 million years ago and split up about 100 million years ago. Right in the middle of that time period, around 250 million years ago, was a massive extinction event called the Permian–Triassic extinction event, also known as the Great Dying. Exactly what caused the Great Dying isn’t known (there are all kinds of theories ranging from an impact event to increased volcanism to large methane releases from the sea floor) but it’s clear that life thrived on Pangea before the Great Dying and that life slowly recovered on Pangea afterwards.
ETA:
Wikipedia article on the Permian period, which has some info on what life would have been around, both on land and in the oceans:
Similar article about the Triassic period:
The Great Dying:
Here’s a little bit about possible climate. had to look under the Mesozoic Era
Just a Wiki, I await more informed answers, but it basically says it may have included desert areas. Note, it doesn’t say it was all a vast desert, but it may include desert areas.
.
Actually, poking around a little more, it turns out that you may be onto something.
yes, large parts of it were arid desert and may have spurred the evolution of arid-tolerant reptiles. We know this from the large evaporite deposits there, and the steady polewards migration of the coal-forming areas. We also know the coast experienced monsoon-like climate, and the higher latitudes were often glaciated. But for the interior, modelling estimates mean summer temps upwards of 40 deg. C.
ouch - that’s hot!
thanks for the comments, everyone - very interesting.
so, any thoughts on the question of marine life in the other half of the world? I’m curious whether the arrangement where all the continents were on one side of the globe, leaving the other half as ocean, would affect marine life?
Just beacuse there were not continents on the other side of the world, doesn’t mean there were not islands, or reefs, or seamounts. Also, there is plenty of life in today’s mid-ocean, far away from continents, so I would image there was marine life back then mid-ocean as well.
Two factors affected marine life when Pangea was formed. First, the total area of continental shelf would have decreased enormously because the seas that formerly occupied the spaces between continents were gone, and there was a smaller area of continental “edge.” Second, as the continents pushed together the continental crust was compressed and got thicker, so the average height of continental crust increased. With continental crust compressed into a smaller area, the ocean basins became proportionally larger. Since there was a fixed amount of water to fill a larger area, sea level became lower and the seas retreated from much of the remaining continental shelf.
The continental shelves are where the greatest diversity and abundance of sea life is found, because the water the is fertilized by minerals in the sediments eroded from the continents. The open ocean is comparatively a desert. For this reason, the formation of Pangea was in general detrimental to marine life.
You know who’d know for sure? Mr. Burns, from The Simpsons.
Q. “Place of birth?”
A. “Pangaea.”