Saturday 20 June 2009

Human Evolution on Trial - Polynesian Origins

Polynesian Origins


The New Zealand Maori language is part of the Eastern Polynesian group. We can use this fact to help us understand Polynesian origins. The defence will use the Polynesian language group itself as evidence in “Eastern Polynesia” [Polynesian Languages].


Language Families Eastern Polynesian languages are spoken on most islands across the central Pacific Ocean from Hawai‘i in the north, Easter Island in the southeast and New Zealand in the southwest. All the languages within the triangle are quite closely related and have probably diversified only in the last 1500 years or so.

As well as Eastern Polynesian the Polynesian group includes Western Polynesian: Tongan, Samoan and some other related languages, both nearby and far to the west. The Far Western Polynesian languages are called the “Polynesian Outliers”. These are scattered through parts of Eastern Melanesia: New Caledonia, Vanuatu and the Southern Solomon Islands. Most of the Melanesian languages are not Polynesian although some are related to it. The Polynesian Outliers are generally accepted as resulting from a movement west of languages from the central Pacific.


Polynesian as a whole is classified in turn as part of the Austronesian language group (Houghton 1980). As well as Polynesian this group includes all the other languages spoken in Fiji, Vanuatu and New Caledonia along with most languages in the Island Southeast Asian subpoint of the human star: Malaysia, Indonesia, Micronesia and the Philippines (Howe 2003). Some languages spoken in Taiwan also belong to the Austronesian group.

Many languages spoken at the northwestern end of Melanesia (The Solomon Islands and the Bismark Archipelago) are also included in this group although most languages of Northern Melanesia are not related at all to the languages discussed here. They belong to the “Indo-Pacific” family. The Indo-Pacific family includes the languages of the Andaman Islands, most languages spoken in New Guinea and possibly the extinct Tasmanian language. We’ll return to the significance of this several times later during the case (“Pacific Population” [Hoabinhian] and “Into Australia” [Indo-Pacific and Pama-Nyungan]).


All the Austronesian languages, along with Austro-Asiatic (the languages of Kampuchea and Vietnam but also found in pockets outside these countries), Thai-Kadai (languages of Thailand, Laos and neighbouring areas) and Miao-yao (scattered through much of South China) may be related to each other. They are sometimes grouped into an Austric family of Southeast Asia and Southern China (Cavalli-Sforza 1995). All these language groups within the Austric family may be reasonably closely related to each other and share a comparatively recent common ancestry. More distantly the Austric family is considered by many to be related to the Sino-Tibetan group from Northern China and Tibet, which makes sense.

Ultimately it may even be related to the Na-Dene branch of American Indian. This branch includes the Athapascan languages (Greenberg and Ruhlen 1992). All these languages possibly descend from a single language or closely related group of languages. The languages presumably long ago expanded from just a single small region.



The defence claims we can find this region if we examine the evidence available. This exercise will help the jury understand the wave theory. Here is the language family tree. Remember Indo-Pacific is not included here. It is not related at all to these languages.


For a start linguistic evidence points to Taiwan as being the point of origin of at least the Austronesian group of languages (Bellwood 1978). Mitochondrial DNA evidence also tends to support this (Underhill et al 2001).



Genes



The study of Polynesian mitochondrial DNA (mtDNA) and Y-chromosomes conducted by a team of people from around the world including Dr. Geoff Chambers of Victoria University in Wellington, New Zealand, (Underhill et al 2001) is an example of the cooperative use of culture for the accumulation of knowledge. The scientists have shown virtually all the female lines (mtDNA) of Polynesians can be traced back to Taiwan but most male lines (Y-Chromosome) come from islands on the way out to Polynesia: Island South East Asia, New Guinea and Melanesia. This implies several things.



First that male and female lines can be different. The defence asks the jury to remember this. Gene flow between two populations has occurred. You will see that this is a fairly common occurrence. In relation to modern times Steve Olson (2002) mentions that within some groups of South Americans virtually all their Y-chromosomes are European while their mtDNA is from local Indian people. This is not at all surprising when you think about it. When we later look at ancient human migration into the Americas (“North to Alaska” [Genetic Expansion]) the mitochondrial DNA and Y-chromosome evidence will again come together convincingly.



Secondly the jury can see from this that the Polynesian languages coincide with the mtDNA line rather than with the Y-chromosome (Underhill et al 2001). Many studies show that in other parts of the world language distribution seems to have a closer relationship with male movement and the distribution of Y-chromosomes rather than with mtDNA. However, in relation to the expansion and mixing of tribal groups in Africa, Basil Davidson (1974) wrote; “it was the mothers who decided what the children spoke, not the fathers”. Mothers probably usually pass on language to their children but the language a population speaks is determined by a complex set of factors. You will see during this case that language expansion is sometimes associated with mtDNA, sometimes with the Y-chromosome, sometimes with nuclear DNA and sometimes it seems to be independent of any of these. Each individual case is different. We usually call the language we grow up with our “mother tongue” though.



Thirdly the evidence suggests the mobile population was in some way matriarchal in organisation. More adventurous males from the south may have introduced the incoming females to the islands though. Either very few women from the south joined the migration or their mtDNA died out. (I understand some recent research has found one mtDNA line in Polynesia that originates from New Guinea).



Societies



The pattern of human Y-chromosome and mitochondrial DNA distribution through most regions of the world has been interpreted as showing long distance movement of Y-chromosomes with locally more mobile female populations. In roughly 70% of modern human societies women move to live with their husband’s family (Jobling et al 2004). But there is a possibility this pattern may have developed as recently as the last few thousand years as a consequence of organised armies, especially those equipped with bronze or iron weapons (but even stone would do).



On the other hand many anthropologists believe that even in apes “it is generally females that leave, or are abducted from, their native group when they mate” (Ridley 2000).



But this may be largely a figment of male anthropologists’ wishful thinking. When we actually look at the evidence we see that although it does occur occasionally in gorilla groups there is certainly no general tendency for it to happen in chimpanzee society.



Marc Swartz and David Jordan (1980) write “chimpanzees also have a distinctly casual social grouping in which only the mother and her offspring form a stable unit in an otherwise shifting series of relations”. And Jane Goodall (1990) has written “there is no closer relationship in chimpanzee society than that between a mother and her grown daughter”. Adolescent female chimpanzees are sometimes kidnapped or wander off to join neighbouring groups when sexually receptive but permanent transfer is actually fairly exceptional. It is usually only orphans that swap groups (Goodall 1990). We also know that chimpanzee brothers tend to remain together. Even in the case of gorillas “it seems that maturing individuals are more likely to migrate when there are no breeding opportunities within the group into which they are born” (Fossey 1983).



The defence suggests it is most probable human populations have effectively behaved in much the same way for much of our history. Perhaps we still do.



Such things as Jewishness (Hammer et al 2000) and the Scottish clan you belong to are said to pass from your mother. It is interesting that in China surnames were transmitted through the female line until as recently as about 500 BC (Cavalli-Sforza et al 1994).



We’ll come back to some implications of this in “Culture” [Families] but species that travel in small herds or groups are often matriarchal. Examples of this phenomenon are found throughout the animal kingdom: red deer populations (Putman 1988), wild horses, turkeys, dolphins, elephants and lions. The herd usually consists of an old female and her female descendants with assorted male hangers-on. The males are usually from other families. This limits inbreeding (“Hybrid Vigour and Inbreeding” [Inbreeding]).



We know that the first few years are the most important for many aspects of our individual cultural development. In so-called primitive societies (and probably in most societies in earlier days) children are breast-fed until they are at least three years old. The men actually have very little to do with the young children. Many families in Western society today are in fact one-parent families (to judge from letters to newspapers we would be forgiven for thinking that in New Zealand most of them were). The single parent in these families is almost always the mother.



In the case of human groups it seems that although males (with their Y-chromosomes) may wander more, be first into a new environment, make the first hybrids with neighbouring groups and introduce or pick up new technology, it is mainly women who transmit culture from generation to generation.



Luigi Luca Cavalli-Sforza (1995) has even suggested that, to some extent, we can think of “cultural heritability”. His research shows social class is highly inherited. Children usually adopt the religion of their mother for example. This inheritance is not genetic of course. What children grow up with they accept as their “Culture”. Most cultures do have initiation rites for young men and women but these usually don’t take place until at least early adolescence. By then most social beliefs are well established in the individual.



Taiwan



Ultimately though the pattern of mtDNA lines in Polynesia may just reflect the fact that until at least some women reached an island there was obviously no possibility of establishing a population. Women whose mother or grandmother had travelled would be more likely to travel themselves but this still involves culture.



The evidence shows that a move south from Taiwan to as far as the Philippines occurred between 7000 and 5000 years ago (Bellwood 1978 and Howe 1984). Taiwan would have been isolated from the mainland since sea level rose at the end of the last ice age about 10,000 years ago. This implies that there had probably been an earlier movement of people possessing an improved boating technology into Taiwan from somewhere else.



The diagram of the diversification of the languages [Language Families] shows the Austronesian languages in Taiwan appear on two different branches. This suggests a ripple of movement, and probably transmission of technology, north from the Philippine Islands to Taiwan. The development of the improved boating technology in Island Southeast Asia was probably the result of a complicated series of population movements in the region.



These movements would not have been single migrations by single groups of people. They may have extended over hundreds, if not thousands, of years. They would have been similar to the migrations already mentioned of Europeans to New Zealand or Anglo-Saxons to England.



New technology has usually led to population expansion. In this case the new technology that allowed the migration may have been the dugout canoe. Canoes of birchbark built around a frame of branches were used in North America when Europeans first arrived there. Birchbark canoes may have been brought in with the first immigrants 10,000 to 15,000 years ago. Therefore they may have been invented that long ago. Dugout canoes may have been used in Europe as early as 7000 BC, 9000 years ago. People were able to get to some remote Mediterranean Islands by then (Attenborough 1987 and see “The Last Point”). Who knows where the dugout canoe developed? It had presumably developed early enough to provide the transport for the Austronesian-speaking people through Island Southeast Asia. But people of the “Hoabinhian” culture from mainland Southeast Asia had been using stone adzes for many years before this. We’ll follow the migration out into the Pacific Ocean and come back to the Hoabinhian (and a map of their distribution, map 5) next in “Pacific Population”. For now we’ll follow the northern line back in time.



Japan



There is a string of islands to both the northeast and to the south of Taiwan leading to either Japan or the Philippines. Some evidence suggests people went both ways. In fact there are indications many elements of the Austronesian technology were actually introduced to Island Southeast Asia from the north, direct from Japan (the extreme end of the East Asian point of the human star) rather than via the mainland (Bellwood 1978). This technology is the “microlithic” the defence mentioned in “Mythconceptions” [Modern Myths].



The Southeast Asian expansion certainly seems to have some sort of connection to Japan. I have seen a photograph of a “Late Jomon” (from 3000 to 4000 years ago) Japanese pottery figure (Clark 1969, the drawing on the right in map 4) that shows similarities to some Maori designs. It also has similarities to what are usually called “Celtic” designs. In “North to Alaska” [Later Migrations] the defence will suggest a reason for this. An example of a Jomon pot is shown at the bottom left. A couple of examples from the Siberian microlithic are included in the upper left. But any connection doesn’t show up in the genes.



The map of the third principal component of the distribution of genes in Asia from Cavalli-Sforza et al (1994) does show evidence of an expansion from around the Sea of Japan (map 4). It may have occurred at the appropriate time. Sakhalin Island is not included in Cavalli-Sforza’s map and so I have not shaded it in mine but it is reasonable to suppose that at least the southern end should be shaded. The Ryukyus are not included either.



Cavalli-Sforza’s map also shows the expansion may have moved across Central Asia as far as the Caspian Sea and Turkey. The opposite genetic extreme is split between India and the very far north of Siberia. I have not shown the Central and West Asian region in my map but I’ll come back to it in Part V (“North to Alaska” [Later Migrations]). I have drawn shoreline at times of lowered sea level although sea level rose throughout the world from about ten thousand years ago.



Unfortunately Cavalli-Sforza’s map doesn’t include Taiwan, Island Southeast Asia, the Pacific Islands or North America. Nor does only the Japanese genetic extreme show up in any of his world maps but wooden boats have been found in Japan and dated to six or seven thousand years ago.



Cavalli-Sforza (1995) has written “Between ten and fifteen thousand years ago, Japan was linked to the mainland – with Russia in the north and Korea in the south – and had its own internal sea. As a result, the area developed uniquely on the back of the sea’s fishing potential”. He goes on to say “The population five to six thousand years ago was already very large and numbered some three hundred thousand, thanks to the development of fishing techniques”.



Na-Dene



Many people have also noticed a similarity in culture between the Pacific Coast of North America and the Pacific cultures generally. Of course this could be due to some later contact. But Cavalli-Sforza (1995) says “it is possible that the Japanese expansion may be linked to one of the old stone-age or Palaeolithic migrations from eastern Asia to America”.



Some evidence does suggest the Na-Dene-speaking people may be genetically distinct from the bulk of the indigenous population of America. They certainly look more Asian (Flannery 2001). Their languages are definitely distinct. Rather than being related to the “Eurasiatic superfamily” all the other American Indian languages are related to Joseph Greenberg and Merritt Ruhlen (1992) consider them to be distantly related to the Sino-Tibetan group of languages discussed here. The defence will eventually be able to use the evidence to construct a complete language family tree (“Culture” [Languages]). From that the jury will see how the wave theory also explains the American Indians’ evolution (“North to Alaska” [Later Migrations]).



The island chains of the Kurile and Aleutian Islands provide an obvious route from Japan to North America for a sea-going people. Originally the Na-Dene may have moved into the islands and coast west of the Canadian Rocky Mountains. This region may not have been occupied at all by any mammoth hunters who had moved into North America near the end of the ice age, about 12,000 years ago. A migration through an ice-free corridor east of the Rocky Mountains would have diverted northern migrants from this coastal region. The Na-Dene people may have been in America for as long as the mammoth hunters although I have seen a time of 6200 years suggested and even 5250 (Lewin 1999). Some groups of the Na-Dene have moved further south, probably as recently as 1000 years ago. They have given rise to the Navaho and Apache people (Olson 2002).



I suggest the Na-Dene people of northwest North America may be part of the same population expansion that gave rise to the Polynesians. They are simply opposite ends of a cline. This would mean that all the languages in the earlier diagram could be derived from a group of languages spoken around the Sea of Japan. Perhaps as recently as 5000 or as long ago as 15,000 years. The Japanese today speak a language that is part of a different, huge language group called “Eurasiatic”. It was almost certainly introduced from Korea only about two and a half thousand years ago. The Ainu language of Northern Japan is also usually classified as Eurasiatic. I would suggest it had been introduced earlier along with the microlithic technology. The defence will show in Part V that the microlithic has connections to the ancestors of the European side of the New Zealand family as well. In other words it is possible the two main groups in New Zealand today developed at opposite ends of an ancient widespread cline. The microlithic technology must have arrived in Japan before the language though because the expansion that gave rise to the Na-Dene and Polynesians must have started before the Ainu language had become established. As the defence said before, it is usually wandering males who introduce technology.



So the Polynesians probably developed as part of a whole complex of population movements around the western margin of the Pacific Ocean from about 10,000 years ago, the end of the ice age. We’ll now return and follow the southern line’s movement into the Pacific Ocean.


See next :: Human Evolution On Trial - Pacific Population





Witnesses Called





Attenborough, David (1987) The First Eden. Guild, London.

Bellwood, Peter (1978) Man’s Conquest of the Pacific. Collins, Auckland.

Cavalli-Sforza, Luigi Luca, Menozzi, Paolo and Piazzi, Alberto (1994) The History and Geography of Human Genes. Princeton University Press, New Jersey.

Cavalli-Sforza, Luigi Luca and Cavalli-Sforza, Francesco (1995) The Great Human Diasporas. Addison- Wesley

Clark, Grahame (1969) World Prehistory. Cambridge University Press, UK.

Davidson, Basil (1974) Africa in History. Paladin, UK.

Flannery, Tim (2001) The Eternal Frontier. (UK/US) Text Publishing, Australia.

Fossey, Dian (1983) Gorillas in the Mist. Penguin, England.

Goodall, Jane (1990) Through a Window. Houghton Mifflin Company, Boston.

Greenberg, J. and Ruhlen, M (1992) Linguistic Origins of Native Americans. Scientific

American, 267 –94-99, Munn and Co., New York.

Hammer et al (2000) Jewish and Middle Eastern Non-Jewish Populations Share a Pool of Y-chromosome Haplotypes. Proc. Natl. Acad. Sci. Vol.97 pp. 6769-6774.

Houghton, Phillip (1980) The First New Zealanders. Hodder and Stroughton, Auckland.

Howe, K. R. (1984) Where the Waves Fall. George Allen and Unwin, Australia.

Howe, K. R. (2003) The Quest for Origins. Penguin, New Zealand

Jobling et al (2004) Human Evolutionary Genetics. (UK/US) Garland Science, New York.

Lewin, Roger (1999) Patterns in Evolution. Scientific American Library, New York.

Olson, Steve (2002) Mapping Human History. Houghton Mifflin Company, New York.

Putman, Rory (1988) The Natural History of Deer. Cornell University Press, New York. (UK/US)

Ridley, Matt (2000) Genome. Harper Collins, New York.

Swartz, Marc J. and Jordan, David K. (1980) Culture - The Anthropological Perspective. John Wiley and Sons, Canada.

Underhill et al (2001) Y-Chromosome Haplotypes and Implications for Human History in the Pacific. Human Mutation 17: 271-280.


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