Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff, Lauren Vogelbaum. Here in elementary school, we learn some indisputable fundamental facts. Two plus two equals four. The world's round. There are seven continents on Earth, but that last one isn't quite so cut and dried. Here in the United States, students learned that there are seven continents North America, South America, Europe, Asia, Africa, Australia, and Antarctica. But that's hardly the last word on the matter.
And much of Europe students learned that there are six continents Africa, America, Antarctica, Asia, Australia's slash Oceania, and Europe. There's a five continent model which lists Africa, Europe, Asia, America, and Oceanica slash Australia. And that's, by the way, why there are five rings on the Olympic flag. And some experts think that four is the way to go, using as their criteria land masses now truly separated by water rather than man made canals, so Afro, Eurasia, America, Antarctica,
and Australia. As recently as the eighteen hundreds, some people said that there were just two continents, the old including Europe, Africa, and Asia, and the new encompassing North and South America. So what really makes a continent a continent? We spoke via email with Dan Montello, a geography professor at the University of California, Santa Barbara. He said, nothing really determines a continent except historical convention, a bit of an overstatement
but mostly valid. Certain factors make a landmass more or less likely to be called a continent at various times in history by various people, but nothing can be said to determine continentality in a completely principled, non arbitrary way. Take, for example, the vast country of Russia six point six million square miles or seventeen million square kilometers. Why has it often been counted as part of you up rather
than Asia? Montello explained. The Ural Mountains are taken to separate Asia and Europe, but only because Russians wanted their great city of Moscow to be European, so the Urals were a convenient marker for that arbitrary decision. Continents are mostly spatially contiguous collections of land masses larger than countries but smaller than hemispheres. Of course, continents do not necessarily fit entirely within single Earth hemispheres and thus cannot be
defined by ranges of latitude or longitude. Okay, so how about plate tectonics. If certain land masses are constrained to one of those massive shifting hulks, can we safely call it a continent? Montello says, no quote. Plate tectonics has nothing to do with it historically, and it certainly could not provide a principal basis for continents. Now, nearly every continent includes parts of multiple plates, the same those for climate.
After all, continents contain multiple climates, as evidenced by Alaska's arctic chill compared with Florida's humid heat. They're both part of North America. Mountain ranges and coastlines are useless too, as our culture and politics, Montella said. Neither ethnicity, race, culture, nor politics has ever defined continents, except by conventional theories that were largely mythical, such as old and fallacious ideas
about correspondences between races and continents. Politically, Hawaii is part of the US, but is in Oceania rather than North America. Greenland is controlled by Denmark for now, but is considered part of the North American continent. So really it boils down to whom and when you ask, Montello said, no one can say, as a matter of principled fact, how many continents there are, because the decisions are largely based on convention, and convention that goes in and out of
fashion over time and is still debated today. He concedes that these days many geographers would opt for a list of seven continents Africa, Antarctica, Asia, You're up, North America, Oceania, and South America, but he added that some of them would combine Asia and Europe into Eurasia, identify Oceania in other ways, or combine North and South America into the America's. He said, there is simply no BZAR or CEO of continents or any other ultimate authority, so it's pretentious for
anyone to claim that they have the authoritative answer. But don't worry if you can't handle that kind of definition. It's all changing. The continents are drifting at a rate of about an inch or two point five centimeters per year. Today's episode was written by Nathan Chandler and produced by Tyler Clang. For more in this lots of other topics. Visit how stuff works dot com. Brain Stuff is production
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