Once upon a time, there was a single great continent – click HERE – called Pangaea. It formed 335 million years ago, was surrounded by the vast Panthalassic Ocean and only began to break apart about 175 million years ago. North America dislodged itself from Pangaea and started drifting west; this went on until its plate rammed into the Pacific plate and the movement dissipated but not before the Rocky Mountains swelled up and reached great heights.
As the North American piece broke off, it carried flora and fauna with it. But today we know that many land species here did not come on that voyage from Pangaea; even the iconic American bison (now the National Mammal) did not originate here. How did they get to North America? Something of a mystère.
Today the Bering Strait separates Alaska from the Chukchi Peninsula in Russia but, over the millennia, there were periods when North America and Eurasia were connected by a formation known as the Bering Land Bridge, aka Beringia. Rises and ebbs in sea level due to glaciation, rather than to continental drift, seem to be what creates the bridge. When the land bridge resurfaces, animals make their way from one continent to the other in both directions.
Among the large mammals who came from Eurasia to North America by means of the Bering Land Bridge were the musk ox (click HERE), the steppe mammoth, the steppe bison (ancestor of our bison), the moose, the cave lion (ancestor of the American lion) and the jaguar. The steppe mammoth and the American lion are extinct today.
Among the large mammals native to North America were the Columbian mammoth, the sabre-toothed tiger, and the dire wolf. All three are now extinct; for an image of the three frolicking together in sunny Southern California, click HERE .
The dire wolf lives on, however, in the TV series Game of Thrones and this wolf is the sigil of the House of Stark; so it must also have migrated from North America to the continent of Westeros – who knew !
Also among the large mammals native to North America are the caribou, the brown bear, the short-faced bear and the tapir. The latter two are sadly extinct today.
In school we all learned how the Spanish conquistadors brought horses to North America, how the Aztecs and Incas had never seen mounted troops before and how swiftly their empires fell to much smaller forces as a result. An irony here is that the North American plains were the homeland of the species Equus and horses thrived there until some 10,000 years ago. Indeed, the horse and the camel are among the relatively few animals to go from North America to the more competitive Eurasia; these odd-toed and even-toed ungulates prospered there and in Africa – even Zebras are descended from the horses that made that crossing. The caribou also crossed to Eurasia where they are known as reindeer.
Similarly, South America split off from Pangaea and drifted west creating the magnificent range of the Andes Mountains before stopping.
The two New World continents were not connected until volcanic activity and plate tectonics created the Isthmus of Panama by 2.8 million years ago – some say earlier (click HERE). The movement of animals between the American continents via the Isthmus of Panama is called the Great American Interchange. Among the mammals who came from South America to North America were the mighty ground sloth (click HERE ).
This sloth is now extinct but some extant smaller South American mammals such as the cougar, armadillo, porcupine and opossum also made the crossing. The opossum and the ground sloth are both marsupials; before the Great American Interchange, there were no marsupials in North America as there are none in Eurasia or Africa.
The camel, the jaguar, the tapir, the short-faced bear and the dire wolf made their way across the Isthmus of Panama to South America. The camel is the ancestor of today’s llamas, vicuñas, alpacas and guanacos. The jaguar and tapir have found the place to their liking, the short-faced bear has evolved into the spectacled bear but the dire wolf is not found there today; it is unknown if it has survived on the fictional continent of Essos.
The impact of the movement of humans and dogs into North America is a subject that needs extensive treatment and must be left for another day. But one interesting side-effect of the arrival of humans has been the movements of flora in and out of North America. So grains such as wheat, barley and rye have been brought here from Europe, the soybean from Asia, etc.. In the other direction, pumpkins, pecans, and cranberries have made their way from North America to places all over the planet. Two very popular vegetables, that originated here and that have their own stories, are corn and the sweet potato.
North America gave the world maize. This word came into English in the 1600s from the Spanish maiz which in turn was based on an Arawak word from Haiti. The Europeans all say “maize” but why do Americans call it “corn”? Mystère.
In classical English, corn was a generic term for the locally grown grain – wheat or barley, or rye … . Surely Shakespeare was not thinking of maize when he included this early version of Little Boy Blue in King Lear where Edgar, masquerading as Mad Tom, recites
Sleepest or wakest thou, jolly shepherd?
Thy sheep be in the corn.
And for one blast of thy minikin mouth,
Thy sheep shall take no harm.
So naturally the English colonists called maize “Indian corn” and the “Indian” was eventually dropped for maize in general – although Indian corn is still in widespread use for a maize with multicolored kernels, aka flint corn. If you want to brush up on your Shakespeare, manikin is an archaic word that came into English from the Dutch minneken and that means small.
That other culinary gift of North America whose name has a touch of mystère is the sweet potato. In grocery stores, one sees more tubers labeled yam than one does sweet potato. However, with the rare exception of imported yams, all these are actually varieties of the sweet potato. The yam is a different thing entirely – it is a perennial herbaceous vine, while a sweet potato is in the morning glory family (and is the more nutritious vegetable). The yam is native to Africa and the term yam was probably brought here by enslaved West Africans.
The sweet potato has still another language problem: it was the original vegetable that was called the batata and brought back to Spain early in the 1500’s; later the name was usurped by that Andean spud which was also called a batata, and the original vegetable had to add “sweet” to its name making it a retronym (like “acoustic guitar” , “landline phone” and “First World War”).