Cook Islands Populations Today, in Relation to European Mixtures and Inter-Island Crossbreedings*

Home , Cook Islanders, Cook Islands, Mangaia, Pukapuka, Rarotonga, Titikaveka (electorate)

J. Anthrop. S㏄. Nippon 人類誌 96(1): 47-59(1988)

Cook Islands Populations Today, in Relation to European Mixtures and Inter-island Crossbreedings*

Kazumichi KATAYAMA1), Akira TAGAYA2), Hiroyuki YAMADA3)and Keiichi KAWAMOTO3)

1)Department of Physical Anthropology, Faculty of Science, Kyoto University 2) Department of Anatomy , Osaka City University Medical School First Department of 3) Anatomy, School of Dentistry, Aichi-GakuinUniversity

Abstract As a preliminary study for analysing human biology data, recently collected from Cook Islanders, the reliability of the data in representing the indigenous population of the pre-European period has been assessed in three islands of the Cook group, Rarotonga, Mangaia, and Pukapuka, in terms of the population changes since European contacts and the ongoing process of mixture with foreign strains and of inter-island crossbreeding among the residents. All the islands surveyed suffered a decline in population after European contacts to a moderate extent, but the degree was far slighter than many islands in Eastern Polynesia, suggesting that random genetic drift did not so seriously affect these island populations as to change the genetic compositions significantly. Concerning gene flow from outside through European admix- tre and inter-island crossbreeding, the effect appeared to have advanced pro- foundly on Rarotonga, slightly on Mangaia, but rather negligibly on Puka- puka. It has been concluded that the present-day populations of Pukapuka and probably of Mangaia are still qualified enough to represent the prehistoric indigenous populations, but that on Rarotonga, even living pure-blood Poly- nesians cannot be considered as representative of the pre-European Raro- tongan population.

Keywords Cook Islands, Polynesia, Depopulation, European mixture, Inter- island crossbreeding

* The present study was financially supported by a Grant-in-Aid for Overseas Scientific Survey, No. 60042012 and 61041072, from Japan Ministry of Education, Science and Culture. Article No. 8716 Received June 26, 1987 48 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO

In 1985 and 1986, two anthropological whereas in Western Polynesia including field surveys collecting somatometric, der- Samoa and Tonga, the process occurred to matoglyphic, odontological, and serological a lesser extent. samples were carried out in some of the Next, it is doubtless true that almost all Polynesian islands of the Cook group. the present-day island populations in Poly- These samples will be analysed with aims nesia have more or less suffered a dilution of identifying the physical characteristics of native stock by European and other of early Cook islanders, describing inter- foreign admixture. In many of the island island variations, evaluating their affinities groups, mixture with foreign strains has with neighbouring South Pacific island been going on for at least one century and populations, and drawing inference about a half. According to SHAPIRO (1940), in the the migration history of human populations island groups, such as the Hawaii, Mar- in the Cook Islands. quesas, and Society islands, the islanders Certain problems arise in such a study, have freely cohabited with sailors, traders, which lead to caution in drawing firm con- beachcombers, missionaries, contract la- clusions. The most significant problem is bourers or tourists who have visited their the reliability of the samples in represent- shores, and consequently unmixed natives ing the indigenous population of the pre- are hard even to find. In many cases, na- European period. It has been sometimes tives themselves are unaware of any foreign argued that present-day Polynesian popula- admixture in their lineage although the tions more or less differ from those of the traces seem obvious to the observer. Thus, past due to the drastic changes in society many scholars are inclined to emphasize the since European contacts. The main factors external influence upon the native popula- responsible for change in traditional indi- tions, but few attempts have been thus far genous populations are a marked decline in made to get substantial data on the effect population, an introduction of foreign genes, in Polynesia. and an increase in inter-island marriage. In addition, we can easily suspect that Physical characteristics could hardly be with the changing way of life of inhabitants expected to remain the same, especially and the improvement of transportation in where rapid depopulation has occurred, be- recent times, the inter-island exchange of cause random genetic drift is quite likely to Polynesian genes has rapidly increased affect populations in such a situation. Ac- through inter-island marriage, as elsewhere cording to MCARTHUR (1967), in many areas in the world. of Polynesia, almost unbelievable population The present Cook Islands population, also, losses seem to have happened, mainly due is likely to have been more or less affected by to the outbreak of introduced diseases fol- such factors. Thus, before examining the bio- lowing European contacts. The intensity logical data, this paper presents some demo- of such depopulation, however, seems to graphic data on population changes since have not been the same either in area or European contacts, and on the ongoing pro- in time. In areas of Eastern Polynesia such cess of mixture with foreign strains and of as Easter, Hawaii, Tahiti, and the Marquesas, inter-island crossbreeding among residents the depopulation was early and very severe, on the islands, Rarotonga, Mangaia, and Cook Islands Populations Today 49

Pukapuka. Based on this data, the genetic suspect the randomness of each sampling contribution of non-Polynesians, other archi- either. pelagic Polynesians, and other Cook island The Cook Islands and The Inhabitants populations to each island population is evaluated, and the representativeness of the The Cook Islands consist of 15 islands, data collected during the field surveys is scattered over more than two million square assessed. In addition, before discussing kilometers of the South Pacific ocean (Fig. these matters, a brief reference is made to 1). From the geographic and historical environmental and historical aspects which background, two distinct groups are dis- will affect any interpretation of the above tinguished there ; the southern Cooks con- factors. sisting of nine islands, Mangaia, Rarotonga, Mauke, Atiu, Mitiaro, Takutea, Manuae, Materials and Methods Aitutaki, and Palmerston, six of which are The source material includes various kinds volcanic and three atolls ; and the northern of statistics presented by other researchers Cooks consisting of six atolls, Penrhyn (BEAGLEHOLE and BEAGLEHOLE, 1938; HA- (Tongareva), Rakahanga. Manihiki, Puka- TANAKA et al., 1982; LANGE, 1982; MC- puka, Nassau, and Suwarrow. ARTHUR, 1967; SHAPIRO, 1930; SHAPIRO A vast distance intervenes between the and BUCK, 1936; SULLIVAN, 1923; WILLIAMS, groups, so that even now, they are con- 1838) and published by NEW ZEALAND nected with each other only by the trading STATISTICS DEPARTMENT (1925-1977; schooner of 300 tons or so, which visits 1980) and COOK ISLANDS STATISTICS once in one to three months. It has been DEPARTMENT (1986), which have been reported that there are considerable ethno- used mainly for making clear the population changes, and the information on the islanders' pedigree obtained through personal interviews and questionnaires, which has given the basis for the evaluation of admixture and crossbreeding. The questionnaires have been collected from school children with the help of native interpreters. The children were asked for the native places of their parents, often of their grandparents, and when suspected of foreign admixture, of their great grandparents. The subjects were randomly sam- pled at the Titikaveka, Tereora, and Nuku- tere colleges in Rarotonga, at the Mangaia primary school and college in Mangaia, and at the Pukapuka primary school in Puka- puka. No exclusion of siblings was made Fig. 1. Map Showing Territory of the Cook in each sample, but there is no reason to Islands. 50 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO graphic (BURROWS, 1938), linguistic (PAWLEY, but he did not see Rarotonga though he 1966), and physical anthropological (SHAPIRO sailed close to it (BEAGLEHOLEand BEAGLE- and BUCK, 1936; HOWELLS, 1970) differences HOLE, 1938). Rarotonga's first European between the natives of these two groups. visitors were probably the mutineers of the Also there is a vast difference between the Bounty in 1789 (MAUDE, 1958). Of the mountaneous islands of the southern group islands of the northern group, almost all and the atolls of the northern group in seem to have been first visited by European ecological conditions and hence in carrying navigators at some later dates, but only capacity. The volcanic southern islands Pukapuka seems to have been visited by have large well-watered fertile land areas Commodore BYRON on his voyage around enough to grow various kinds of vegetation, the world in 1765, who named it the Island whereas the northern atolls comprise only of Danger. After the first visits of Euro- a tiny palm-laden strip of sand, where the peans, the Northern atolls seems to have dwellers have traditionally subsisted on co- been more rarely visited by Europeans than conut products, supplemented by fish and the Southern Islands frequented by trading pandanus. and whaling ships, presumably because of At present the resident population of the their isolation and the proverty of natural Cook Islands is estimated less than 20 thou- resources. sand, nearly 90% of whom are in the Apart from intermittent visits of Euro- southern group. A larger population than pean vessels, substantial European contact those currently living in all the islands are began with the missionary endeavors of the living in New Zealand and Australia, as London Missionary Society. Fairly soon temporary residents. after the Rv. John WILLIAMS of the Society The capital, Avarua, is on Rarotonga, visited Aitutaki in 1821 and Rarotonga in where the number of inhabitants reaches 1823, missions were started one after approximately ten thousand, and the popula- another in the 1820s to the 1840s in all the tion is still increasing mainly due to immi- islands of the southern group, for example, gration from the other islands of the Cooks. in 1827 on Rarotonga and in 1845 on Man- There we can see some kind of urbani- gaia. Not until the latter half of the 19th zation ; the government administration century, however, did the missionaries offices, merchant offices, tourist facilities, reach the islands of the northern group. and various sorts of factories are centered Thus, it is evident that Rarotonga and on this island. Mangaia have been in an intimate associa- It is generally accepted that the southern tion with Western civilization for a slightly group of the Cook Islands came to the at- longer period of time than Pukapuka. There tention of Europeans after the visit of Cap- seems, however, to have been no substantial tain James COOK in 1773 during his second settlement by European traders or planters voyage. At that time, he sighted only one on any of the islands until the 1860s. island which he named as Hervey Island Population Change (Manuae) in honor of the Honorable Captain HERVEY. Mangaia itself was visited by Fig. 2 presents the temporal change of Captain COOK on his third voyage in 1777, population since European contact in each Cook Islands Populations Today 51

Fig. 2. Temporal Changes of Population on Rarotonga, Mangia and Pukapuka.

of the surveyed populations. All the figures pean contact. The outbreak of some epi- in the present century are based on the demic seems to have begun around the end official census of NEW ZEALAND STA- of 1829 and to have been worst in devasta- TISTICS DEPARTMENT (1925-1977) and tion in the early 1830S. It is said that the COOK ISLANDS STATISTICS DEPART- disease was dysentery together with fever MENT (1986), but those in the previous and ague, and that the epidemic was ac- century have been obtained from various celerated by an attack of famine and a hur- kinds of sources (WILLIAMS, 1838; BEAGLE- ricane and caused many deaths, probably HOLE and BEAGLEHOLE, 1938; and LANGE, numbering nearly one hundred a day. Thus, 1982) of somewhat doubtful reliability. In the severe depopulation in the 1820S to 1840S spite of this restriction, we can compare of Rarotonga is coincident in time with the the trends of population change on the is- outbreak of such diseases. After the 1840S, lands for nearly two centuries. the population there kept decreasing until At a glance, a considerable degree of de- just the beginning of this century, probably population should be noted on all the islands because it could not recover the potential surveyed, but both the starting time and rate of reproduction during the period. the intensity somewhat differ from island Since the 1900S, however, it began catching to island. On Rarotonga, it had started by up and at last around 1960, was able to the 1840s, probably in the 1820S, but on restore the pre-1820 position, this probably Mangaia it did around 1850. On Pukapuka, being attributable to the recovery of the it seems not to have been until the 1860S previous reproduction rate as well as to the that the depopulation started. increase of immigration from the other is- According to MCARTHUR (1967), Rarotonga lands of the Cook group. is the only population in the Cook Islands There was certainly a tendency toward known to have experienced very high mor- depopulation also on Mangaia after the tality from introduced diseases after Euro- 1840s, and it continued to exist until around 52 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO

1920. At the 1916 census, the population European contacts, though not uniform decreased to nearly one third of the 1840S either in time or in intensity. At the same estimate. On Mangaia, however, there are time, however, it can be said that the Cook few reports of the deadly influence of in- Islands have escaped their losses in numbers troduced diseases, although some mission- relatively lightly, when compared with aries reported the minor effect of such Hawaii, the Marquesas, and the Societies. epidemic diseases as dysentery, scarlatina, In Hawaii, the native population declined and measles in the 1840S and 1850S. There- from Captain COOK'S estimate of 400,000 in fore it is reasonable to assume that the 1779 to about 23,000 pure Hawaiians steady loss of population after the 1840S is recorded by the United States census in attributable mainly to the emigration of 1930 (SHAPIRO and BUCK, 1936), and in young men from the island, either as crew the Marquesas the number fell off from on the boats calling there, or as servants some 100,000 to scarcely 2,000 during nearly to the European residents in Tahiti, as sug- the same period (SULLIVAN, 1923). Like- gested by MCARTHUR (1967). In addition, wise, the Society Islands seem to have suf- it is noted in Figure 1 that on Mangaia, fered a heavy loss of aboriginal inhabitants there was a temporary population increase (SHAPIRO, 1930). Thus, also in the Cook at the period between the 1820s and the Islands, population losses certainly occurred 1840s. Presently we have no means of to some extent after European contacts, but ascertaining if it really took place since we the degree was far slighter than those in cannot consider the population estimate in the areas of Eastern Polynesia, so that we 1823 of WILLIAMS (1837) as absolutely relia- cannot consider the depopulation itself as ble, but the presence might be supported having had a significant influence on the by PITMAN'S note (MCARTHUR, 1967) that genetic composition of the indigenous popula- Mangaia's population was increasing in 1844 tions there. For Rarotonga, however, and by the evaluation of MCARTHUR herself another possibility should be pointed out that in the 1840S the number of births per that the traditional native population has adult female on Mangaia was roughly twice more or less changed its genetic constitu- the rate on Rarotonga. tion, rather due to the population increase A considerable portion of the depopulation through a considerable amount of immigra- between the 1850S and the 1880S of Puka- tion from the other islands of the Cooks, puka might be well explained by BEAGLE- which has occurred in the present century. HOLE and BEAGLEHOLE's (1938) note that Peruvian slavers twice visited the atoll European Admixture and about 1863 and removed about 100 men and Inter-island Crossbreeding women, only two of whom returned to Each school child, who was asked to Pukapuka, and that further in 1869, Captain answer the questionnaire, has been classified ENGLISH of the ship R. W. Woods landed according to the ethnic origin or native is- in Honolulu 42 natives of Pukapuka, lands of parents, of grandparents, and some- Anyway, it must be concluded that these times of great grandparents. Usually, the islands have suffered a rather serious deci- native island is not necessarily the same as mation of their inhabitants consequent to the birth place. Actually in Polynesia, how- Cook Islands Populations Today 53 ever, many people (especially old people) to obtain trustworthy information on the can easily remember the native islands of original place of the grandparental and/or anyone's parents, so that it is not difficult of the great grandparental generation, how- to identify a person by his or her ethnic ever, we have to remain content with a proportion. As it was not always possible somewhat restricted basis of classification

Table I. Classification of Subjects by Their Ethnic Proportion A. Rarotonga Sample

B. Mangaia Sample 54 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO in some cases. Additionally the word "pure" been excluded from the calculation here, is used here to designate an individual because they might have been temporary whose parental, grandparental, or great residents at the time of survey. In many grandparental birth places are identical, so aspects, there is a noteworthy difference that there is no guarantee that he or she between the samples, especially between has no other ethnic descent in the remoter Rarotonga and the other two. Based ancestors. on the data in these table and figures, Table 1 shows the classification of sub- several points should be noted concerning ject children by their ethnic proportion in the ethnic constitution of pupulation or the the Rarotonga, Mangaia, and Pukapuka sam- amount of foreign mixtures and of inter- ples. For example, the uppermost row of island crosses. Table lA means that of 198 children sam- First, in both the Mangaia and Pukapuka pled on Rarotonga, 37(18.7%) have both samples, almost all the subject do more or the parents of pure-blood Rarotongan, 63 less have the native descent of their own (21.8%) are half-to-half mixture of native island, while nearly 40% of the Rarotonga Rarotongan and any other ethnic parentage, subjects have not any native Rarotongan 79(39.9%) have no Rarotongan descent at background at all, and in other words, all, and so on. more than one-third of present-day Raro- Fig. 3 is to compare the genetic contri- tongans are immigrants from outside the bution of ethnic origin groups to the pre- island or their descendants. Second, in sent-day Rarotonga, Mangaia, and Pukapuka the Mangaia and Pukapuka, the number of populations. The percentages have been genuinely native children reaches about two estimated from the data in Table 1, divid- thirds of the whole sample, while in the ing the sum of individual proportions by Rarotonga, only about 20% of the children the total number of subjects. Pure-blood can be described in this way. Third, as Europeans, Asian Indian, and Africans have for inter-island crosses in the Cook Is-

Table 1 (Continued) C. Pukapuka Sample

* including Fijian Cook Islands Populations Today 55

Fig. 3. Estimation of the Genetic Contribu- tions of Ethnic Origin Groups to Each Present-Day Population. A. Rarotonga Population B. Mangaia Population C. Pukapuka Population

lands, the percentage frequency can be as- pean descent. No child of European admix- sessed for each island from subtracting the ture exists in the Pukapuka sample, but percentage of its pure-blood natives from instead there are three descendants of that of pure-blood Cook Islands Maori, and Micronesian (Kiribati) admixture, probably as a result, the descendants of inter-island due to the geographic proximity to Micro- crossbreeding are greatest in number in nesia. There is only one subject with one- Rarotonga (approximately 46.0%), next in half Chinese background in Rarotonga. Mangaia (approximately 27.7%), and smallest Fifth, the influence from other Polynesian in Pukapuka (approximately 20.5%). Fourth, stocks is recognized in seven children (3.5%), in Rarotonga, the number of pure-blood one child (0.7%), and nobody in the Raro- Europeans and European mixtures reaches tonga, Mangaia, and Pukapuka samples, 33.8% of the whole sample. There are respectively, being considered as insignificant twelve European mixtures (8.1%) in the in amount. Mangaia sample, but almost all of them are For reference, Fig. 4 shows the temporal hybrids with less than one-quarter Euro- changes of the non-indigenous population 56 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO

throughout the present century. As con- trasted with Rarotonga, Mangaia and Puka- puka have maintained non-indigenous populations at a level even lower than the combined Cook Islands. On Pukapuka, the percentage once became rather high (about 3%) round 1926, but the exact reason is outside the scope of the present study. Incidentally, SHAPIRO (1942) reported that of 232 adult inhabitants for his anthropometric study, Fig. 4. Temporal Changes in Percentage of twelve were European mixtures, eight were Non-Indigenous Population on Rarotonga, hybrids with other Polynesian groups, and Mangaia, Pukakuka and the Combined Cooks. four were descendants of crosses between Kiribati Islanders and Pukapukans. Since his on Rarotonga, Mangaia, Pukapuka, and the subjects might all have been young adults, the combined Cook Islands. The data have been European mixtures were possibly borne in obtained from New Zealand Official Year the 1920s. Therefore, exceptionally many Books (NEW ZEALAND STATISTICS DE- Europeans might have been living there in PARTMENT, 1925, 1931, 1947 and 1956), the 1920S for some reason. but are regrettably not available after 1956. Thus, we can draw a conclusion about The non-indigenous means here mainly the foreign admixture that at present a Europeans or half-castes living as Europeans. larger European population has settled on The standard to assign someone as non- the islands of the southern group such as indigenous seems rather ambiguous, sup- Rarotonga and Mangaia than in Pukapuka. posedly depending on his or her statement. Even allowing for a sampling bias due to Thefore, it is not easy to directly compare small sampling in Pukapuka, it is apparent these data with those we have got. If in that the Pukapuka population has been much Table 1, persons with more than three- less influenced by European admixture than quarters foreign descent are only considered Rarontoga and probably than Mangaia. Ac- as non-indigenous, the percentage can be cordingly, it is clear that European genes estimated at 7.0%, 0%, and 0% for the have been unequally distributed among the present-day Rarotonga, Mangaia, and Puka- Cook Islands according to the geographic puka populations, but if all persons with and commercial conditions of the islands. more than one-half foreign parentage are On the one hand, especially in the present- included, it becomes 14.6%,1.4%, and 2.3% day Rarotongan population, the genetic in- for the present-day Rarotonga, Mangaia, and fluence of Europeans seems quite significant Pukapuka populations, respectively. in degree, and therefore without any special Anyway, the Rarotonga population has treatment, it is difficult to manage the sort been composed of much more non-indigenous of study we have intended. On the other residents than the Mangaia and Pukapuka hand, the influence seems still negligible populations, and has maintained a moderately even at present on Pukapuka, and also on high percentage of foreign descendants Mangaia, not significant though greater than Cook Islands Populations Today 57 on Pukapuka. As for the genetic influence estimated at 5.3%,1.2%, 0.2%, and 5.6, re- of other ethnic groups and Polynesians out- spectively, from data of substantially the side the Cooks, however, we can safely say same kind as in Tables 1ABC, which were that all the populations surveyed have not collected by HATANAKA et al. (1982). The experienced it to a considerable extent. Reoa Atoll is considered to be one of Unfortunately, we can hardly examine the most isolated islands in Eastern Poly- the figures presented here in relation to nesia, but the genetic influence of Eeropeans general Polynesian patterns, because few is much greater in amout than those of attempts have been made thus far to get Pukapuka and Mangaia, though smaller than substantial data of this sort in South Pacific that of Rarotonga. At the same time, the areas. The only available data are for New genetic contributions of Chinese and of the Zealand Maori and from Reao Atoll in the outside Polynesians are greater in Reao Tuamotu archipelago of French Polynesia. than in any of the Cook islands surveyed. The data for New Zealand Maori are given As for the amount of inter-island cross- in Fig. 5, the figures of which we have breeding, too, Rarotonga differs from Puka- calculated in nearly the same method as puka and Mangaia. In the present-day those for the Cook Islands populations sur- Rarotongan population, gene flow is esti- veyed, based on the official census of 1976 mated to reach 34.1% of the genetic com- (NEW ZEALAND STATISTICS DEPART- position from the other islands of Southern Ment,1980). In the New Zealand Maori, the group and 10.5% from Northern group, as genetic contribution of Europeans reaches shown in Fig. 4A. This means that of nearly 40%, being far greater than that of individuals without any foreign admixture, Rarotonga. For the Reao Atoll, the genetic approximately a half have come from the contributions of European, Chinese, African, other islands of the Cook group, partly as and Polynesians outside the Tuamotus are rather recent immigrants and partly as the result of inter-island crossbreeding. Thus, we suggest that on Rarotonga, a great part of living pure-blood Polynesians do not represent the pre-European Rarotongan population anymore, and as a result, the traditional indigenous population has nearly col- lapsed already. In other words, in a genetic sense, it might be difficult to consider the present-day Rarotongan population as a single breeding unit anymore. However, we may still consider them as representative of the entire Cook Island Maori, because of the rather small genetic influence of the outside Polynesians on them. On Mangaia and Pukapuka, however, the Fig. 5. Estimation of the Genetic Contribution of the Genetic Contributions of Ethnic Origin genetic contribution of the other islands of Groups to New Zealand Maori Population. Cook group is relatively small in amount. 58 K. KATAYAMA, A. TAGAYA, H. YAMADA and K. KAWAMOTO

In the Mangaia population, such an influence 片山一道・多賀谷昭・山田博之・川本敬.__. still remains as low as about 16% of the genetic composition, the main part of which クック諸島に居住するポリネシア人から収集した生 are from the other islands of the Southern 物学的資料を分析するための予備的研究として,ヨーロッパ人との接触期以降の人口変動,外国人(特にヨ group and exclusively through inter-island ーロッパ人)との混血状況 ,クヅク諸島内の島間の通 marriage. Thus, we can suggest that the 婚状況などを検討することによって,現代人から収集 present-day Mangaian population still retains した標本がどの程度までヨーロッパ人との接触以前の the genetic characteristics of early Man- 先史クック諸島集団を代表しうるのかという問題を考 gaians to a considerable extent, so that it 察した.対象としたのは,南部クック諸島のラロトン sufficiently represents the pre-European ガとマンガイアの両島,北部クック諸島のプカプカ環 Mangaian population and even though 礁で,いずれも指掌足紋,歯型,血液型,生体計測な modestly speaking, the Southern Cook Is- どについての生物学的資料を収集した集団である. lands population. In the Pukapuka popula- 主な成績は次のように要約できる. tion, the genetic influence from the other 1.対象3島ともに,ヨーロッパ人との接触以降, Cook islands is still smaller than is the ある程度の人口減少を経過しているが,マルケサス諸 Mangaia. Therefore, we can consider the 島,ソサイティー諸島,ハワイなどの東ポリネシアの島嘆と比較するとその程度は遙かに軽微なものであ present-day Pukapuka population as suffici- る.従って,いずれも人口規模が極端に小さなもので ently representing the native population はないことから,遺伝的浮動が各島の遺伝的構成を大 before European contact also in this respect. きく変容させた可能性は小さいようである. 2.ラロトンガでは,ヨーロッパ人などとの混血や Acknowledgment クック諸島内の他島との通婚が著しく進行しており, The authors are indebted to Associate その結果,同島では遺伝子流入の影響でヨーロッパ人 Professor Norio SHIBATA, Indonesian Lau- 到来以前の集団の個性をもはや失ってしまっている可能性が高い. guage Institute, Faculty of Foreign Langu- 3.これに対し,プカプカでは,混血や通婚は今な age, Tenri University, for his collaboration お極めて少なく,遺伝子流入による集団の変容は無視 in collecting statistic data in New Zealand. できる程度のものと言ってよい.マンガイアでも,混 We particularly wish to express our thanks 血や通婚による外来要素の流入は予想外に少なく,簡 to Mr. Shephered Opere ME'A, Dental Officer 単な系図チェックで確認できそうである. of Mangaia, Department of Health, Govern- 4.以上のことから,プヵプカとマンガイアでは, ment of the Cook Islands, for his kind as- 現代の島民の標本からヨーロッパ人との接触以前の先 sistance in making the questionnaire survey. 史集団の身体特徴を推測することは可能であるが,ラ We would like to thank Dr. Kaa HENRY, ロトソガでは同島のポリネシア人をもはや単一の繁殖 Dr. Warwick HANSON, Dr. Jane BoROKY, 集団とみなすことはできなくなっており,先史ラロト and other staff at the Dental Division of ンガ集団を復元することは容易ではないと結論できる。 Health Department, Government of the Cook References Islands, for their cooperation in the course of the field survey. BEAGLEHOLE, E, and P. BEAGLEHOLE, 1938: Ethnology of Pukapuka. Bernice P. Bishop Museum Bulletin, no. 150, Honolulu. 抄録 BURROWS, E. G., 1938: Breed and border in Polynesia. Amer. Anthropologist, 41: 1-21. クック諸島集団の現状一特にヨーロッパ人との COOK ISLANDS STATISTICS DEPARTMENT 混血と諸島内の通婚について (ed.), 1986: Cook Islands Key Facts. Raro- Cook Islands Populations Today 59

tonga, Dept. of Statistics, Cook Islands. Wellington. HATANAKA, S., J. M. CHAZINE, K. KATAYAMA, PAWLEY, A. K., 1966: Polynesian languages: a J. KOMAKI, E. NITTA and N. SHIBATA, 1982: sub-grouping based on shared innovations in Reao Report-A Study of the Polynesian Migra- morphology. J. Poly. Soc., 75: 37-62. tion to the Eastern Tuamotus. Kanazawa, SHAPIRO, H. L., 1930: The Physical Characters The Uuiversity of Kanazawa. of the Society Islanders. Memoirs of Bernice HOWELLS, W. W., 1970: Anthropometric group- P. Bishop Museum, Vol. 11(4), Honolulu. ing analysis of Pacific peoples. Archaeol. and SHAPIRO, H. L., 1940: The distribution of blood Phys. Anthrop. in Oceania, 5: 192-217. groups in Polynesia. Amer. J. Phys. Anthrop., LANGE, R. T., 1982: A History of Health and 26: 409-416. Ill-Health in the Cook Islands. A thesis sub- SHAPIRO, H. L., 1942: The anthropometry of mitted for Ph. D. degree at the Univ. of Otago, Pukapuka-based upon data collected by Ernest Dunedin. and Pearl Beaglehole. Anthrop. Papers Amer. MAUDE, H. E., 1958: In search of a home. J. Museum of Natural History, 38: 141-169. Poly. Soc., 67: 104-131. SI-IAPIRO,H. L, and P. H. BUCK, 1936: The Phy- MCARTHER, N., 1967: Island Populatison of the sical Characters of the Cook Islands. Memoirs Pacific. Canberra, Australian National Univ. of Bernice P. Bishop Museum, Vol. 12(1), Press. Honolulu. NEW ZEALAND STATISTICS DEPARTMENT SULLIVAN, L. R., 1923: Marquesan Somatology. (ed.), 1925, 1931, 1945, 1946, 1947, 1956, 1967 Memoirs of Bernice P. Bishop Museum, Vol. and 1977: New Zealand Official Yearbook. 9(2), Honolulu. Wellington, Dept. of Statistics, New Zealand. WILLIAMS, J., 1838: A Narrative of Missionary NEW ZEALAND STATISTICS DEPARTMENT Enterprises in the South Sea Islands. London, (ed.), 1980: Birth places and ethnic origin. John Snow. (cited from MCARTHUR, 1967). 1976 Census of Population and Dwelling, Vol. 7,

片山一道京都大学理学部自然人類学研究室〒606京都市左京区北白川追分町

Kazumichi KATAYAMA Laboratory of Physical Anthropology Faculty of Science, Kyoto University Sakyo-ku, Kyoto 606, Japan