Year: 2019

The incredible shrinking southern continent

As an American, I’ve always been accustomed to clearly defined state, national, and continental boundaries. The border between Canada and the United States, for example, may be an arbitrary line of latitude, but we all know exactly where it is—what’s in, and what’s out. We know exactly where North America stops and Central America starts; we also know when we’ve reached the easternmost or westernmost edge of the continent because we run into an ocean. Sure, there’s the odd island off the coast here or there, but conceptually, these cause no problems for my notion of what a continent is.

The map of South America, though, has always offended my sense of geographical tidiness. At the southern end of the continent, the land sort of swoops out to the east—but wait, that last big chunk is actually an island. Is that part of the continent? And what about the bazillions of smaller islands littering the coastline to the south and west? If I’m on one of those islands, am I on the continent or not? The geological answer is yes—I’m on the same continental plate. The political answer is also yes—any given spot of any given island is uncontroversially under the control of either Chile or Argentina. But to the average person on the street (or boat, as the case may be), these boundaries are neither visible nor intuitive. Today, we can get the answers to such questions from highly accurate maps. Hundreds of years ago, though, the answers were far less obvious. Speculation about continental boundaries led to some fanciful maps, tall tales, and grand adventures.

What Goes Around

I was standing in a museum in a town on Tierra del Fuego—a name given to the entire archipelago of little islands at the tip of South America as well as to its largest island, which is known more properly as Isla Grande de Tierra del Fuego. (For other articles I’ve written here about Tierra del Fuego, see Ushuaia, Extinction of the Yámana, and Pan del Indio.) On the wall was a map from the 16th century showing the landmass we know today as South America extending all the way south to connect with a vast southern continent much larger than Antarctica. In other words: an unbroken stretch of land all the way from pole to pole. This hypothetical continent, which also encompassed Australia, had a detailed imaginary coastline that was represented as being accurate, even though no cartographer had come anywhere near it. Europeans at the time referred to this continent as Terra Incognita (the Unknown Land)—or Terra Australis (the Southern Land). In the 4th century BCE, Aristotle had advanced the idea that a great southern continent must exist, because without it the world would be top-heavy. This view was later expanded on and popularized by Greek geographer Ptolemy in the 2nd century CE. But as of the early 16th century, no European had actually seen this land.

In 1520, Ferdinand Magellan became the first European explorer to discover a sea route from the Atlantic ocean to the waters west of South America, to which he gave the unfortunate name “Pacific ocean.” But as he was passing through what came to be called the Strait of Magellan, with South America clearly on his right, Magellan could also see land to his left. When he realized the channel went all the way through, he drew what was for him the logical conclusion: that land he’d seen to the south must be the tip of the great southern continent. He gave it the name Tierra del Fuego (“land of fire”) upon seeing the smoke rising from numerous fires built by the land’s inhabitants. This name, of course, suited the continent’s popular image as a mysterious and forbidding place. And Magellan’s discovery—apparently the first proof of the existence of Terra Australis—required only minor modifications to the maps of the time.

Down and Out

It was not until 1578 that Francis Drake, in an attempt to circumnavigate the globe, discovered the truth about Tierra del Fuego. Drake sailed through the Strait of Magellan, but his ship was blown south by a storm; he soon found himself rounding the tip of a large island chain. Now there was another way to get between the oceans—the Drake Passage. Although Drake did not sail all the way to Antarctica, he again drew the logical conclusion that it must be down there somewhere—as in fact, by chance, it was. Shortly thereafter, in 1616, Cape Horn—at the tip of Horn Island—was identified as the southernmost point of land that could be construed as part of South America. In the 18th century, captain James Cook discovered the location of Australia—and that it, too, was not the imagined southern continent, its new name notwithstanding. Only in the early 19th century did explorers first set foot on Antarctica and begin to correct the old maps once and for all.

All of the foregoing is, I’m sure, familiar to anyone who (unlike me) actually paid attention in history and geography classes. But it was a revelation to me, looking at an old map in a museum, that assumptions about the nature of the world—unsubstantiated though they were—could have led to such startling errors, such blatant (if well-meaning) fabrications, and so many years during which myths were misrepresented as fact. True or not, deeply ingrained beliefs die hard. If you never thought you could learn anything from history, keep this little lesson in mind as you read today’s news.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on February 22, 2005.

Image credit: NASA [Public Domain]

It’s Penguin Awareness Day! OK, on the count of three, everyone be aware of penguins. One…two…three! Boom. Done.

If you want to be extra aware of penguins today, here are some suggestions:

• See some penguins in person at your nearest zoo
• Read up on Magellanic penguins right here on Interesting Thing of the Day
• Watch Happy Feet or March of the Penguins
• Catch up on Bloom County
• Discover that yes, penguins actually do have knees
• Install Linux

Image credit: Pexels

Less buzz for your buck

Every day it seems medical researchers come out with a new study about coffee, how it is extremely unhealthy for you and/or full of amazing benefits. The focus of most of these studies is more particularly about the effects of caffeine on human health, caffeine being coffee’s most potent element. As caffeine is a stimulant, it can produce both positive and negative effects. It can wake you up in the morning, but it can also lead to sleeplessness, a racing heartbeat, and anxiety.

It is therefore no surprise that many people have decided to cut caffeine out of their diets. What I sometimes find surprising is how many people still opt to drink coffee, just without the caffeine. I have grown to like the taste of coffee, but to me the main purpose of drinking it is to get an extra jolt of energy.

I’ll admit to a certain prejudice against decaf, perhaps prompted by bad experiences in the past with weak and tasteless brews. It is true that the actual process of removing caffeine from coffee can degrade the taste beyond repair, but new methods of decaffeination have been developed to help the coffee retain more of its flavor in the process. In addition, researchers continue to look for and cultivate new strains of coffee plants that produce beans with a naturally low level of caffeine. This may all spell good news for those who still crave coffee without its kick.

Buzz Kill

Early decaffeination attempts involved soaking the green beans in water and then using various solvents to separate out the caffeine in the resulting water solution. The beans were then re-introduced to the caffeine-free solution in order to absorb some of the flavor they had lost. Solvents used included benzene, chloroform, and trichloroethylene, all of which were later found to have toxic effects. In the 1970s, dichloromethane came into use to replace the earlier solvents before it too was deemed possibly carcinogenic.

In response to these concerns about solvents, some coffee companies began to run the water solution through charcoal filters as a means of removing the caffeine. The so-called Swiss Water Process, developed in Switzerland in the 1930s, goes one step further. After a batch of coffee beans has been steeped in hot water, that water is filtered (the resulting solution is referred to as “flavor-charged”), and then is used to soak the next batch of beans to be processed. In this way, the beans lose caffeine as they soak, but lose less of their flavor. Currently there is only one official Swiss Water Process plant in operation in the world, located near Vancouver, British Columbia.

Yet another method that aims to safely remove caffeine from coffee beans involves a fascinating chemical process. The solvent used in this method is neither water nor one of the earlier toxic solvents. Instead, caffeine in the coffee beans is dissolved by means of carbon dioxide. In order to accomplish this, the carbon dioxide must become a supercritical fluid, created when it is compressed and heated to the point that it has the same density in liquid and gaseous forms. As this supercritical CO₂ is passed through the beans, it can penetrate them because of its gaseous properties, and yet is able to dissolve the caffeine they contain because of its liquid properties.

Hold the Caffeine

All these decaffeination methods are useful in extracting the caffeine from beans that already contain it, but how much more efficient would it be if the beans themselves contained less caffeine in their natural state? In 2004, news reports came out that Brazilian scientists had identified three coffee plants from Ethiopia that contain almost no caffeine; these plants seemingly lack an enzyme necessary to caffeine production. Since then, owing to various difficulties cultivating commercially viable versions of these plants, it seems no substantial progress has been made in bringing this coffee to market. Complications have included very low yields from the caffeine-free plants, the problem of pests (since caffeine seems to be the plant’s way of protecting itself from predators), and the inability to prevent cross-pollination with other caffeine-laden plants.

Although researchers around the world continue to search for the perfect way to cultivate caffeine-free coffee plants, for now the current methods of decaffeination will have to suffice for decaf junkies seeking their fix of coffee that not only tastes great, but won’t keep them up half the night. As for me, I do want to stay up half the night, so I’ll stick to my full-strength brew.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on June 15, 2007.

Image credit: Pixabay

I liked popcorn as a kid, and then—for reasons I am at a loss to explain—I went through a multi-decade period of not liking it. But now I’m back to liking it again. As long as it’s buttered and seasoned, that is. Or covered with caramel or chocolate or whatever. (Plain, unsalted popcorn is pretty disgusting.) I don’t know why today was designated National Popcorn Day but I do know that movies go really well with popcorn. So head on down to your local popcorn dealership today, and pick up some movies while you’re at it.

Image credit: Logicaldisaster~commonswiki [GFDL or CC-BY-SA-3.0], via Wikimedia Commons

Saskatchewan’s shifting sands

Picture of a part of the world covered with enormous sand dunes. You may be thinking of a desert in Africa, Asia, or the southwestern United States. But there’s another place, above the 49th parallel, where you can find such sand dunes—Saskatchewan, Canada. Many people associate Saskatchewan with its prairie landscape, but although the southern half of the province—where you’ll find major cities such as Regina and Saskatoon—is mostly prairie grasslands, the northern half is a wild expanse of rivers, lakes, and coniferous forests. In its south-central region it even has a salt lake with a salinity that is half that of the Dead Sea, Little Manitou Lake (Cree for “Lake of Good Spirit”). And Cypress Hills, in the southeastern corner of the province, is the highest point in Canada between Labrador and the Rockies. This diversity is not so surprising when you consider that Saskatchewan is twice the size of Italy and almost as big as Texas.

Located in the far northwest corner of Saskatchewan, almost at the border with the Northwest Territories, the province’s largest lake, Lake Athabasca, is accessible only by floatplane, there being no roads that go that far north. On the south side of the lake is a natural geological formation that is unique and surprising to find at this northern latitude—the Athabasca Sand Dunes. In places 30 meters (98 feet) high, and stretching 100 km (62 miles) along the shore of Lake Athabasca, the Athabasca Sand Dunes are the world’s largest area of active sand dunes north of 58 degrees latitude.

Don’t Desert Me

Although we often associate sand dunes with deserts, in the case of the Athabasca Sand Dunes, this doesn’t hold true. For one thing, deserts are identified by their lack of water, and not only do these dunes border 7,850 square kilometers (3,030 square miles) of water, they also contain significant patches of water in places, percolating up from the shallow water table below. Another feature of deserts—limited plant and animal life—does not hold true for these sand dunes either. In fact, of the 300 plant species that grow in the dunes, there are 10 species that are endemic (found nowhere else in the world), and another 42 species that are considered rare in the province. Not that the dunes are entirely welcoming to the local flora. Because the dunes are active, shifted by wind and eroded by water, they are constantly on the move. Visitors to the region tell of seeing entire stands of skeletal trees emerging from the sand—once above ground and flourishing, these trees were slowly buried by the shifting sand, and now are revealed by further dune movements.

So, if these sand dunes are not a desert ecosystem, created by extreme drought and aridity, how were they formed? The short answer is: the glaciers did it. The sand dunes are the product of the Athabasca sandstone formation, originally a delta in a freshwater lake created out of materials eroded from ancient mountain ranges by glaciers and rivers one billion years ago. These materials were eventually compressed into sandstone, and later still, eroded by wind, water, and glaciers to create the sand dunes that exist today. Of course, I also find the native Dene legend about the dunes’ creation interesting—that a giant man speared a giant beaver, which thrashed and ground the earth with its tail, making soil into sand.

Sand by Me

The dunes are now protected as part of the Athabasca Sand Dunes Provincial Park, but there is little infrastructure to welcome visitors. Aside from lack of accessibility (via floatplane only), there are no services available at the site. You need to be well versed in outdoor survival skills, or sign up for a guided tour. For the armchair traveler, you can see stunning photographs of the dunes on the Photo Journeys blog of photographers Robin and Arlene Karpan.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on July 3, 2004.

Image credit: Tim Beckett [CC BY 2.0], via Wikimedia Commons

If you’re looking for a synonym for the word “thesaurus,” forget about consulting the Merriam-Webster online thesaurus: it says there isn’t one. But of course Thesaurus Day honors Peter Mark Roget, eponym of Roget’s Thesaurus, who was born on this date in 1779. The Roget’s online thesaurus also lists no single-word synonyms for “thesaurus,” though it does suggest “storehouse of words” and “treasury of words.” To celebrate Thesaurus Day, go learn some new words! (You can start with eponym if you don’t already know what it means.)

Image credit: Ray MacLean [CC BY 2.0], via Flickr