Eurasia

At first glance, Europe and Asia don’t really seem like they’re different continents.

Think about Russia for a moment: is it European or Asian? The answer is usually: yes. Why, then, should this giant landmass that stretches nine thousand miles from the Atlantic to the Pacific be considered two continents instead of one?

As usual, whenever I’ve found something that perplexes me, there’s a good story behind this.

You probably already know that the Earth’s surface is really a bunch of plates floating around on top of a giant ocean of magma. Keep that image in your mind, and think about all of the sloshing and jostling around, and you have a good idea of what happened when two really big plates smashed into one another about 250 million years ago. This was pretty much right at the start of the age of dinosaurs, or maybe just a hair before they showed up and began to dominate the planet’s ecosystem.

If you could magically transport yourself to that time, you would not find any mammals whatsoever. You also wouldn’t see any flowers, because they wouldn’t evolve for another 50 or 100 million years, give or take. That means you also wouldn’t see any pollen-carrying insects like bees, but you would see some pretty big insects, like dragonflies with wingspans of around two feet (more than half a meter).

You would see no forests full of trees, or at least no trees like the ones we have today. Instead, if you looked up, you’d see an utterly alien canopy overhead. Tall poles covered in thick bark would surround you, looking something like modern palm trees with leaves concentrated all at the top. These pseudo-trees would have much thicker bark than today’s actual trees, lacking any wood for structure.

The temperature would be much hotter than today’s Earth—probably in the range of at least ten degrees hotter—and you’d see dry deserts dominating most of the landscape everywhere you looked.

Speaking of the landscape, the land itself was different. Those floating plates were carrying these proto-forests and deserts around like a cruise ship carrying around thousands of vacationers and crew. One day—and when I say “day” here, I am being very metaphorical—two of these big plates smashed right into one another.

If you could play the tape back at a faster speed, you’d see the spot where the two intersecting plates smash together, crushing the edges together and creating mountains in the process. The land just doesn’t have anywhere to go but up.

These are the Ural Mountains.

This is a bit of an oversimplification. For one thing, there weren’t just two plates involved in the crash. Even still, can you envision this in your mind’s eye? Can you see the titanic crash that created the Urals in your mind?

Ural mountain | malikanile | Flickr

That’s why we think of Europe and Asia as two separate continents today. All the jostling and smashing around of those continental plates on the lithosphere? The shape of our geographic borders is at the mercy of this slow, titanic mosh pit. Every continental shape and every mountain range is there thanks to this phenomenon.

Now, human beings didn’t venture out into Eurasia until much, much later. Our homo erectus ancestors only started exploring the landmass within the last couple of million years, and our modern human ancestors came across Eurasia even later. In other words, the Ural mountains were a long-established feature of the land that must have seemed like the edge of the world for people trying to get to the other side.

Today, this mountain range, created 250 million years ago by a lithospheric mosh pit, still operates as a frontier of sorts.