Why does PNG have so many languages?

IN THIS monthly discussion we answer one question about language in PNG and beyond. This month we are looking at why PNG has so many languages.
It has become a cliché to say that PNG has more languages than any other country on earth. With its more than 830 different languages, PNG has many more different languages than countries with far greater populations.
PNG is not unique in its linguistic diversity. All of its Melanesian neighbours have large numbers of languages spoken by small groups of people. Like PNG, no Melanesian country has one local language that is spoken as a home language by a majority of its citizens.
This is perhaps the greatest cultural difference between Melanesia and Polynesia, such as Samoa, Tonga, and before colonialism Hawai’i and Aotearoa (New Zealand). In each of those Polynesian countries, only one language is spoken. Why is there this vast difference?
A number of scholars have observed that tropical areas with great biodiversity also tend to have a lot of linguistic diversity. This is the case in Melanesia, the Amazon, and central Africa, where there is both great biological and linguistic diversity. There is much less biological diversity in the monolingual countries of Polynesia. But just because there is a correlation does not prove that there is cause and effect. These two types of diversity might just be two unrelated phenomena happening in the same place caused by the kind of geographic barriers we find in rugged tropical continental regions.
One important factor is the time that humans have lived in Melanesia. Melanesia was one of the first areas outside Africa to be settled by modern humans. Because people have lived in this one area for such a long time, their languages have had a long time to become different. Humans have been living in Melanesia for 40,000 to 60,000 years, whereas some areas of Polynesia have not even been settled for 2,000 years, not long enough for languages there to separate into small language communities like they have in Melanesia.
Could it also be that there are psychological or social differences between Melanesia and Polynesia? The late Professor George Grace of the University of Hawai’i thought so. He noted that in Polynesia, there were large kingdoms covering entire island groups, with a strong national identity focussed on a king.
In such societies people would grow up identifying with a large political and cultural unit. In this kind of social environment, there would be travel between different islands and there would be a tendency to try to speak the same way as the king and his advisors. Linguistic and other diversity would not be valued or encouraged.
In Melanesia, on the other hand, pre-colonial political units were small, usually no more than a couple villages or “haus lain”. Grace noted that Melanesian people traditionally preferred to emphasise differences rather than commonalities. We see this today in the comment that neighbouring villages “change the language”, even when the differences are small and do not really make it difficult to communicate.
In such a social environment, especially one with natural mountain, river, and swamp barriers between groups of people, language differentiation would progress at a rapid rate, and people would not feel a need to try to speak like anyone outside their village.
Some linguists think that in the distant past, the linguistic situation in Melanesia was the norm rather than the exception everywhere in the world. They think that in the past all humans lived in small social groups like Melanesians, speaking a large number of distinct languages.
With the invention of agriculture and the growth of large political units in Europe and Asia, certain languages became prestigious and either through war, conquest, or just cultural strength, these languages came to be spoken by large numbers of people, and other languages became extinct.
Even where political units did not emphasise large regions, there were often waves of massive migration, such as with the speakers of the Bantu languages who spread throughout from central to most areas of eastern and southern Africa.
If this theory is correct, the linguistic diversity of Melanesia reflects an earlier time in human development. Melanesia has retained its diversity because of a lack of nations or empires that brought many groups under the control of one language group. Geographic barriers and rising water levels after the first migrations into the region meant that language families from other areas could not have spread into Melanesia until the arrival of European colonists.
Whatever the cause, Melanesia has ended up with a multitude of languages unmatched anywhere else in the world. One quarter of all languages are spoken by the relatively small number of people living in this region. Let us hope that the people and governments of our region will prove to be good stewards of this rich cultural treasure.

• Professor Volker is a linguist living in New Ireland, and an Adjunct Professor in The Cairns Institute, James Cook University in Australia. He welcomes your language questions for this monthly discussion at [email protected]. Or continue the discussion on the Facebook Language Toktok page.