Ecological History and the World Distribution of Languages

      One of the most fascinating aspects of human culture is the enormous variety of languages encountered throughout the world.  Although only a few hundred languages have more than a million speakers, the total number of mutually unintelligible forms of speech is something closer to 5,000, many of which are spoken by only tiny numbers of people.  Linguists have grouped the world's languages into about 25 major families, each presumably descended from a common ancestor spoken in the distant past.

      Most of us have had experience with only a few languages, and it might seem that 5,000 is an enormous number.  Actually, a few hundred years ago the number of languages in the world was probably closer to 7,000.

      Let's first take a closer look at the linguistic diversity that existed five hundred years ago. In 1500 there were probably about 7 thousand languages spoken across the earth, most still groupable into the 25 or so major families represented today.  Although the number of major groupings is about the same, the number of languages in each group, as well as the relative number of speakers in each group has changed dramatically in the past 500 years.  Today, one language family, Indo-European (which includes most languages of Europe, Iran and India) has come to dominate large areas of the world; one out of every two people on Earth is fluent in at least one Indo-European language.  Native languages of the Americas, Australia, and the islands of the Pacific have all but completely disappeared under the onslaught of Indo-European. Thousands of languages in these areas have died out or are spoken by tiny and dwindling numbers of speakers. With the death of tribal elders, the number of languages in the world declines every year.

      The map of 1500, which show only the major language groupings, actually glosses over much of the real linguistic diversity present at that time. The Australian language family was really five very distantly related families each on the order of the Indo-European family. And there were over 1,500 languages in the Americas before Columbus

      One out of every five languages spoken in the world at that time was probably a Native American language.  One out of every 10 people in the world probably spoke a Native American language.  Today the number would be less than one in 10,000.

      Today there remain no more than 5,000 living languages, and many hundreds of these are on the verge of extinction.  Only a tiny remnant of the earth's population speaks one of the surviving Native American lang's.

      Language loss has been greatest in the Americas, Australia and the Pacific Islands, but also significant in Northern Asia and Southwest Africa. In all of these areas, entire language groups have disappeared or have been reduced to tiny remnants spoken in out of the way corners of their former range. Exactly what caused the spectacular expansion of Indo-European languages such as English and Spanish?  And what led to the rapid extinction of so many languages in only a few hundred years?  Obviously, the change was connected with European exploration and colonization of other continents, which began in the late 15th century.  But what exactly happened to the Native Americans after 1492? Or to Australian Aborigines and Pacific Islanders after Captain Cook?

      Many people connect European conquest and colonization with the dramatic linguistic and demographic changes in these areas over the past 500 years.  It is, of course, true that the European arrival coincided with the rapid demise of native peoples and their languages in the Americas, Australia, and the Pacific. 

      But why were the Europeans so stunningly successful in their cultural and demographic takeover of entire continents?  Many people believe that European success overseas derived from sheer ruthless exploitation. Others believe that European success was inevitable due to some sort manifest destiny based on innate superiority of race or religion or both. 

      Today I hope to convince you that neither of these views, nor any combination of them, can provide adequate answers to our question of why some languages thrive and others die out.  Many of the Europeans were indeed ruthless and exploitative; and some aspects of European culture and technology afforded some clear advantages over aboriginal peoples.  But Europe also established colonial rule over Africa and much of Southern Asia--often with equal if not greater exploitation.  In the centuries after Columbus, over 10 million West Africans were forcibly transplanted into North and South America.  Yet Africa is still overwhelmingly African--both demographically and linguistically.

      The 1,000 or so sub-Saharan African langauges are thriving and the European languages left by colonialism are dwindling oases in this native sea.  And Asia is still mostly Asian--both demographically and linguistically.  In fact, since contact with Europeans, the peoples of Africa and Asia have increased greatly in number and their languages are as widely spoken as ever, if not more.  Hundreds of native languages are spoken today by billions of non-European peoples in Africa and Asia--and this despite--or perhaps in part because of--contact with Western culture, which facilitated the global spread of such food crops as Native American corn, potatoes, manioc, sweet potatoes, and a host of other important foods.  

      So why are the Americas, Australia and the Pacific--in sharp contrast to Africa and mainland Asia-- today largely dominated by Indo-European languages even after the colonial era has ended?  Why have such far-flung places as North America, Argentina, Australia, and New Zealand become--for all practical purposes--Neo-Europes both demographically and linguistically? Why the unprecedented die off of many hundreds of Native American and Australian languages?

      Now I will attempt to convince you that most of these changes are due directly or indirectly to an ecological factor not much discussed by linguists up till now--the uneven effect of epidemic disease on competing human populations.

      To implicate disease in the changes, we have to turn to research published by archeologists as well as by disease historians over the past few decades.

      Until recently, historians believed that the Americas, Australia and the Pacific Islands were very sparsely populated 500 years ago compared to Europe, Africa, and Asia at the same time. Older history books speak of the taming of the American "wilderness," the opening up of "virgin" territory. However, it has become increasingly clear from archeological and other evidence that the Americas, at least, were much more thickly populated than was formerly believed.  Pre-Columbian Mexico was probably home to some 25 million people speaking over 250 languages. Similarly, the Andean Empire of the Incas, Tawatsinsuya, was thickly populated and the largest state in the world at the time of Columbus with the possible exception of the Chinese Empire. Even in parts of the territory that was to become the United States there were large populations of Native Americans. Near present-day St. Louis stand the remains of an earthen pyramid that was once nearly as large as the pyramids of Egypt. It is though to have been the religious center of a populous state which flourishes before the time of Columbus.

      The first Europeans to visit the Atlantic coast, in the early 1500's, also spoke of dense populations everywhere. And yet, a century later, when the English began colonizing the American continent, they found it only sparsely populated. What happened to the original native inhabitants?

      The crucial part of our answer almost certainly lies not in the deeds and exploits of individual people--the Cortezes, Columbuses and Coronados--, but in the unequal susceptibility to disease manifested by different groups of people at particular times in history.  For a variety of reasons, a population may become exposed to a disease and gradually build immunity without having to compete simultaneously with another group who already enjoys such immunity.  However, when a disease-tolerant population introduces its germs to a virgin population, the immunologically naive population suffers terribly while the disease-tolerant population remains unaffected. This decisively affects the outcome of the competition.

      The difference in susceptibility to key diseases has played a tremendous role in redrawing the world linguistic map in the past 500 years. The vast majority of people on earth today are the descendants of Europeans, Asians and Africans who for many centuries lived in mutual if desultory contact before the age of European exploration, and who gradually built up a tolerance to a large number of diseases. And the vast majority people on earth today speak languages directly descended from the languages spoken by these immunologically fortunate groups.

      The Old world was the center of animal domestication: many human germs seem to derive from animal diseases which mutated when animals and humans came to live in permanently close proximity (measles from canine distemper; smallpox from cowpox; influenza from pigs and ducks.)  The world's major language families today are those of Europe, Africa and Asia--not of the Americas, Australia, or Oceana, which were before 1492 isolated from the more numerous and more deadly infectious diseases of the Old World.  These areas had far fewer of their own native diseases because they were newer areas of human habitation and, most importantly, had few if any animals to domesticate.

      In his book Plagues and Peoples, disease historian William MacNeill documents the emergence of epidemic diseases in the agricultural and stockbreeding societies of the old world and the gradual exchange and merger of various local diseases through the centuries. The peoples of Europe, Asia and Africa had suffered from all sorts of epidemics of communicable diseases for thousands of years.  Smallpox and measles are thought to have developed in the cities of Western Asia in the Neolithic period--they were once horrible killers and may have helped destroy such peoples as the Sumerians.  Through centuries of contact, Old World peoples unwitting interchanged a large number of communicable diseases, including smallpox, measles, chicken pox, mumps, influenza, certain types of TB, typhus.  But by 1500 the various Old World peoples had emerged with a much higher tolerance for these diseases than had been enjoyed by their ancestors.

      It is easy for us today to underestimate the devastating impact of contageous diseases in earlier periods of human history.  Our historians tend to emphasise the deeds and plans of individual rulers or military leaders and to virtually ignore the accidental effects of biology.  Most people don't realized that in 1920 a worldwide epidemic of influenza killed over 20 million people, nearly double the number of casualties from all the fighting in World War One. Even fewer people realized bubonic plague over half the population of Mediterranean Europe in the 6th century AD, so that the survivors had to acquire large numbers of Slavic tribesman from Central Europe to replentish their work source, giving rise to the Latin word sclavus and ultimately to the English word slave.

      The least forgotten episode of disease in European history is probably the Black Death which broke out in Europe in 1347. Let me refresh your memory on this account.

      The Mongols had been invading Eastern Europe for the past century. It is thought that in the early part of the 14th century AD the Mongols accidentally brought the plague from southern Asia.

      Plague breaks out in the Tatar army besieging the Genoese city of Kaffa, in the Crimea.

      Genoese ships bring plague back to the port of Messina in southern Italy.

      Over the next three years an epidemic of Bubonic Plague sweeps nearly every corner of Europe, killing perhaps 1/3 of the population.  No European war has ever been as devastating as this plague, which returned every generation for three hundred years.  Even in 1492 Europe's population was still less than it had been before 1347.

      But in the long run, the Bubonic Plague was not important in the demography of Europe. The Europeans eventually more than recovered their numbers. Plague only affected the linguistic picture in a few marginal ways (set the stage for the separation of Yiddish from German; killed off 50% of the clergy, hastened the fading of Latin and the rise of vernacular English, Frence, Spanish as languages of learning).

      Imagine what might have happened, however, if the Mongols, who were invading Europe at the time of the plague, or perhaps the Turks, were themselves immune or nearly immune to the plague? (Actually, they were not immune and suffered at least as much as the Europeans.)  If the disease gradient had been in their favor--there might have occurred a permanent demographic shift in Europe from which Indo-European speakers would not have recovered. Or suppose the Germans had had some partial immunity to plague (based on experience with some local germ). German would have quickly become the dominant language of Europe.

      As I have said, many other epidemics occurred in earlier centuries in the Old World.  Some were undoubtedly even more devastating than the Black Death of the 14th century.  But gradually, the survivors of these biological catastrophes in Europe, Africa, and Asia developed immunity or partial immunity to the diseases.  By 1492, such ancient killers as smallpox, measles, chicken pox, and mumps had become little more than childhood nuisances in much of Europe.

      The peoples living in the Americas, Australia, Oceana (and, to a lesser degree, Siberia and the deserts of Southwest Africa) were shielded from the major disease centers of Africa, Europe and Asia for thousands of years.  And since these areas were outside the range of domestication of most animals, they had far fewer diseases of their own. No one in these vast areas had ever had smallpox, measles, pneumonia, whooping cough, mumps, chicken pox, bubonic plague or even the common cold. With the advent of trans-oceanic travel in 1492, the stage was set for biological catastrophe.

      Let's focus on the effect of contact in the Americas, although a similarly tragic story unfolded in Australia and the Pacific islands.

      Within a few decades of 1492, forty generations worth of Old World epidemiological experience--in the form of dozens of diseases--were visited simultaneously upon the immunologically defenseless peoples of the Americas.  Each one of the resulting epidemics of such diseases as smallpox was as destructive as the 14th century Bubonic Plague had been in Europe a few centuries before.  The result was possibly the worst mass mortality in all of human history. 

      Let's reexamine a few historical events from the time of the first European invasion of the American mainland to fill in the epidemiological details normally omitted by traditional historians.

      In 1519 Hernan Cortez invades Mexico without permission of the Spanish king. He visits the Aztec capital of Tenochtitlan, a city of over a quarter of a million inhabitants. (The largest city in Europe at that time was London, a town with about the population of present day Bellingham on a Friday afternoon.) In 1520 another Spaniard, Narvaez, lands in Mexico with orders to arrest Cortez. Cortez leaves the Aztec capital, encounters and defeats Narvaez.  Meanwhile, Cortez's men in Tenochtitlan provoke an uprising and are defeated; over half of them are killed while fleeing the city at night.

      This is what the history books tell us. What we are often not told is that an African slave in Narvaez's company came ashore in 1520 sick with smallpox.  The disease quickly spread to the local Indians and then throughout the country.

      The Aztec capital was hit by smallpox just as the defeated Spaniards were in retreat.  In a few short months perhaps half the population of Mexico, including Montezuma's successor, died of smallpox. The Spaniards return and lay siege to the decimated and half-deserted Mexican capital.

      Now, let's move on to conquest of Peru by Pizzaro several years later. Smallpox decimated the Incas the year before Pizarro's invasion. In 1526, half the population dies of smallpox; the emperor and his son also die and civil war breaks out. Pizarro arrives in 1532 and conquers a country decimated by the worst epidemic and civil war in its history.  And by this time, new epidemics of measles and influenza are ravaging the natives.

      During these epidemics, it was reported that not a single Spaniard in either Mexico or Peru even got sick, let alone died: all the Europeans had had mild cases of smallpox as children and were immune.  Only the Indians caught the disease and died. This pattern was to be repeated on many occasions. It also led to mass conversions of Indians to Christianity, the religion of the biologically immune Spaniards.  

      Within the next 100 years at least 14 major epidemics of smallpox, measles, influenza and other diseases never before encountered by native Americans raged through Central America.  By 1619, European epidemics, followed by European conquest and exploitation of the survivors, had reduced the native population of Mexico and Peru by 90%.  Of perhaps 20 million Mexicans living during the time of Moctezuma, only 2 million are thought to have survived into the next century.  Modern Mexicans are for the most part mestizos--the descendants of the small percent of native who survived the diseases and mixed with their European conquerors. 

      So far we have mentioned the effect of European diseases only on the relatively urbanized societies of Mexico and Peru.  The same catastrophic mortality seems to have affected every corner of the Americas, often before the Europeans themselves even had time to arrive in person.  The first mainland smallpox epidemic which coincided with Cortez' assault on Tenochtitlan in 1520 seems also to have spread to much of the rest of North America.  The Indians, being completely susceptible to the new disease, were excellent carriers, and it spread from tribe to tribe far inland and to the north. 

      Archeological evidence shows that even the Upper Columbia Plateau in Washington State--not visited by whites until Lewis and Clark three centuries later--suffered a 75% drop in population during the first few generations after Cortez. 

      The year before the Pilgrims landed at Plymouth Rock in 1620, 90% of the people living in Massachusetts seem to have died of some unknown epidemic--possibly typhus brought by a European ship on its way to fish off the coast of Newfoundland.  When the Pilgrims arrived, they simply began to live in the houses and fields they found abandoned throughout the countryside. 

      Epidemics of old world diseases continued among each generation of native Americans for three hundred years--preventing them from regaining their former numbers at the crucial time they were coming into competition with European invaders.  Usually, the Indians had lost the war before the first battle with Europeans had even begun, before they had even met any European for the first time. So it would be more appropriate to say that the Europeans did not colonize a virgin land--instead Europe colonized a widowed land.  

      There is a general lesson here about what happens when the group with a technological or military advantage--such as the colonizing Europeans-- also happen to have a greater resistance to disease than the people they conquer.  The answer is that the native peoples die in droves and their cultures and language--if not they themselves, are replaced almost totally--almost as if they had never existed.  This is exactly what happened in much of the Americas and Australia--except in inaccessible regions where population had time to recover from the epidemics before facing direct competition with Europeans, or in farming areas where the aboriginal population was so dense that enough survived to mix with the conquerers and maintain their presence, as in Mexico and parts of South America.

      Europeans--understanding little about the nature of disease-- were awestruck by the rapid decline of the natives.  One German missionary in the 17th century remarked that "the Indians die very fast; the mere sight and smell of a Spaniard is enough to make them give up the ghost." Spanish missionaries sent to Baja California in the 17th century complained that the Indians seemed to melt away in a very short time despite the best care they could give them.

      In areas where European colonization followed fast on the heels of the epidemics, the native tribes had no time to regain their lost numbers.  Theft of land and exploitation of the survivors drove many tribes, who had numbered in the thousands before European contact-- to complete extinction.  This happened to many tribes of the eastern US and especially to the California tribes.  The Carribean tribes--the Taino and Carib-- were almost completely wiped out within two short generations after Columbus.  The aborigines of such exposed areas as Newfoundland, the Texas coast, and Florida--along with their unique languages and cultures-- were utterly wiped out.  Even in areas visited only by missionaries with the most peacible intentions, such as Baja California the native tribes suffered appalling mortality and sometimes became extinct. 

      In the history of the European invasion of America, there was also much outright murder and genocide against the native peoples. In US history this was particularly true in California. But for every one native killed by violence, perhaps 10 were killed silently by the new microcopic invaders.  This latter event did not happen in Asia and Africa during colonization, since Africans and Asians generally already had experience with Europe's arsenal of diseases, hence the survival of native peoples and languages in most of the Old World despite the same brutality which accompanied colonialism in the Americas.

      Thus, the tremendous linguistic changes we see in the Americas, Australia and the Pacific came about due to the combination of the aborigines' susceptibility to Old World diseases and competition by a non-susceptible population.  The only areas of the Old world which experienced significant language die off were South Africa and Siberia--the two area which were most isolated from the main Old World disease pool and which consequently likewise suffered tremendous ecological calamity when the Europeans penetrated them during the Age of Discovery.  Thus, the history of language die off in the past 500 years has very much to do with the history of the spread of epidemic disease.

      However, it is very important to note that the Europeans did not always have epidemic disease as their special ally.  Tropical diseases endemic to Africa and Asia also have played a crucial role in colonial history--and in the history of languages.  Before the age of quinine and other drugs, the would-be conquerers from the European north who entered tropical Africa, were the ones to die in droves, regardless of the advantages of their military technology. In the mid 1800's Englishmen attempted to establish a farming community in Nigeria--a kind of Plymoth Rock on the Niger--within several years they had died of malaria. Tropical diseases kept the Europeans out of the African interior until the advent of improved medicine barely a century ago.

      Imported African diseases also played a pivotal role in the Americas after Columbus. Already within a generation of Columbus the rapid demise of the American natives--the only population available in the new colonies to be exploited as laborers-- encouraged the slave trade in black Africans.  When the slave ships also brought such tropical diseases as malaria and yellow fever from Africa to the Americas, the Europeans as well as the Indians began to die off in tropical America.  The Carribean littoral became a death zone for Europeans as well as Native Americans. (Haiti, in fact, was to become an independent Black African country at the end of the 18th century precisely because yellow fever destroyed Napoleon's troops and emissaries on the island.) Much of the Carribean population today are descendants of African slaves who enjoyed partial immunity to malaria and yellow fever.  Tropical African diseases helped Europe accidentally create Neo Africas in much of the Carribean.  The steady die off of Europeans on many Carribean islands led to the creation of French, Dutch and English creole (mixed) languages in the wake of the diminishing European as these languages were learned imperfectly by adult slaves and then passed on in mixed form as the native language of the next generation of children.

      In the tropics, generally, the disease gradient was against the Europeans.  Even if military advantage gained them the initial victory, the Europeans were ultimately subdued by disease. Tropical diseases not only protected some areas from conquest altogether, they also were a main factor in the development of creole languages on the basis of Indo-European languages.  In tropical Africa and Asia, disease actually protected language diversity. In fact, because of language mixing, the diversity even increased.

      Linguistic textbooks point to trade and economic contact as the chief reason for the development of pidgins and creole languages. However, most of the 200 modern creoles developed when the languages of temperate peoples were imposed on peoples living in tropical areas. And most of the others developed when the remnants of many peoples who had been decimated by disease mixed together and created a pidgin or mixed language of communication. Chinook Jargon is an example.

      Let's look once again at the linguistic map of 1500. Could disease have sponsored language extinction and creolization in centuries past? There is every reason to believe so.

North Africa: Malaria, yellow fever, sleeping sickness, also kept the Arabs and their Islam out of much of Black Africa for the past 1000 years. (Africans used tse-tse flies against the Arab invaders in southern Sudan)

India: (microbial standoff between northern invaders and native tribes accustomed to tropical germs)

China: (creation of Chinese dialects via the same type of interaction)

North vs. Mediterranean Europe (malaria keeps the Germanic peoples mostly north of the Alps)

      We have ample evidence to conclude that disease has played a pivotal role in determining the current world distribution of languages--particularly after 1492 but possibly also at earlier stages of human history.

      Now let's look into the future. Will disease have any future impact on the distrubution of languages? There will undoubtedly be new diseases--and they may have a profound effect on the future history of our species, but it is likely that everyone will be affected more or less similarly by new contageous diseases--since none of us will have had time to develop immunity.  In a world that is increasingly a single global village, it is less likely that future disease will serve as the secret ally of certain languages and a fierce foe to others. The unequal effect of epidemic disease on world language distribution is mainly a tale from the past rather than a lesson about the future.  But it is a tale that needs to be told as a centerpoint in the history of Western Civilization.