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1.
The genus Cochleariopsis Y.H. Zhang was described in 1985, with C. zhejiangensis Y. H. Zhang, the only member of the genus, as its type. However, this species had been published by O.E. Schulz earlier in 1923, named Cochlearia warburgii O.E. Schulz. Hence, this species is not new one, and the type of the ge-nus should be Cochleariopsis warburgii (O. E. Schulz)L. L. Lu .  相似文献   

2.
The genetic ancestry of Polynesians can be traced to both Asia and Melanesia, which presumably reflects admixture occurring between incoming Austronesians and resident non-Austronesians in Melanesia before the subsequent occupation of the greater Pacific; however, the genetic impact of the Austronesian expansion to Melanesia remains largely unknown. We therefore studied the diversity of nonrecombining Y chromosomal (NRY) and mitochondrial (mt) DNA in the Admiralty Islands, located north of mainland Papua New Guinea, and updated our previous data from Asia, Melanesia, and Polynesia with new NRY markers. The Admiralties are occupied today solely by Austronesian-speaking groups, but their human settlement history goes back 20,000 years prior to the arrival of Austronesians about 3,400 years ago. On the Admiralties, we found substantial mtDNA and NRY variation of both Austronesian and non-Austronesian origins, with higher frequencies of Asian mtDNA and Melanesian NRY haplogroups, similar to previous findings in Polynesia and perhaps as a consequence of Austronesian matrilocality. Thus, the Austronesian language replacement on the Admiralties (and elsewhere in Island Melanesia and coastal New Guinea) was accompanied by an incomplete genetic replacement that is more associated with mtDNA than with NRY diversity. These results provide further support for the "Slow Boat" model of Polynesian origins, according to which Polynesian ancestors originated from East Asia but genetically mixed with Melanesians before colonizing the Pacific. We also observed that non-Austronesian groups of coastal New Guinea and Island Melanesia had significantly higher frequencies of Asian mtDNA haplogroups than of Asian NRY haplogroups, suggesting sex-biased admixture perhaps as a consequence of non-Austronesian patrilocality. We additionally found that the predominant NRY haplogroup of Asian origin in the Admiralties (O-M110) likely originated in Taiwan, thus providing the first direct Y chromosome evidence for a Taiwanese origin of the Austronesian expansion. Furthermore, we identified a NRY haplogroup (K-P79, also found on the Admiralties) in Polynesians that most likely arose in the Bismarck Archipelago, providing the first direct link between northern Island Melanesia and Polynesia. These results significantly advance our understanding of the impact of the Austronesian expansion and human history in the Pacific region.  相似文献   

3.
Roy Ellen 《Economic botany》2004,58(4):601-625
Presented here is an examination of the technological process whereby the stem pith ofMetroxylon sagu Rottboell is transformed into edible starch by the Nuaulu people of south central Seram, Maluku, Indonesia. The analysis seeks to describe the underlying local knowledge and practices involved, with a view to refuting the assertion that sago extractionis an intuitively and technically simple solution to food provision for those reluctant to adopt ‘proper’ agriculture. In the light of this demonstration, I reconsider how palm starch dependency works as an adaptive strategy.  相似文献   

4.
Melanesian origin of Polynesian Y chromosomes   总被引:16,自引:0,他引:16  
BACKGROUND: Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians. RESULTS: We analysed eight single nucleotide polymorphisms (SNPs) and seven short tandem repeat (STR) loci on the Y chromosome in 28 Cook Islanders from Polynesia and 583 males from 17 Melanesian, Asian and Australian populations. We found that all Polynesians belong to just three Y-chromosome haplotypes, as defined by unique event polymorphisms. The major Y haplotype in Polynesians (82% frequency) was restricted to Melanesia and eastern Indonesia and most probably arose in Melanesia. Coalescence analysis of associated Y-STR haplotypes showed evidence of a population expansion in Polynesians, beginning about 2,200 years ago. The other two Polynesian Y haplotypes were widespread in Asia but were also found in Melanesia. CONCLUSIONS: All Polynesian Y chromosomes can be traced back to Melanesia, although some of these Y-chromosome types originated in Asia. Together with other genetic and cultural evidence, we propose a new model of Polynesian origins that we call the 'slow-boat' model: Polynesian ancestors did originate from Asia/Taiwan but did not move rapidly through Melanesia; rather, they interacted with and mixed extensively with Melanesians, leaving behind their genes and incorporating many Melanesian genes before colonising the Pacific.  相似文献   

5.
The incidence of 30 minor non-metrical cranial variants in Australian Aborigines discussed in a previous publication is compared with incidence in crania from Melanesia and Polynesia. With the qualification that the sample sizes from Melanesia and Polynesia are rather small, the data indicate that the differences between Australia and Melanesia and Polynesia exceed those between the three areas into which Australia was divided. The area of Australia made up of the Northern Territory and northern Western Australia has more association with Melanesia than Polynesia as expected, while the more southern regions of Australia have more association with Polynesia than Melanesia perhaps by migrations from Asia. Because the southern Australian Aborigines are now largely extinct, it seems difficult to prove this.  相似文献   

6.
Aims: To determine the presence and contribution of diazotrophic bacteria to nitrogen concentrations in edible starch derived from the sago palm (Metroxylon sagu). Methods and Results: Isolation of diazotrophic bacteria and analysis of nitrogen fixation were conducted on pith, root and sago starch samples. Acetylene reduction showed that five of ten starch samples were fixing nitrogen. Two presumptive nitrogen‐fixing bacteria from starch fixed nitrogen in pure culture and five isolates were positive for the nif H gene. Nitrogen concentrations in 51 starch samples were low (37 samples <0·2 g kg?1; 14 ranging from 0·2 to 2·0 g kg?1). Conclusions: Nitrogen fixation occurs in sago starch, which undoubtedly plays a role in fermentation ecology. Nitrogen levels are considered too low to be of nutritional benefit and to protect against nutritional‐associated illnesses. Significance and Impact of the Study: Sago starch does not add significantly to the protein calorie intake and may be associated with susceptibility to nutritional‐associated illness.  相似文献   

7.
Local biological variation is marked in Melanesia. Some of it may result from gene flow from Micronesia, but the essential variation appears to result from isolation due to social fragmentation, and to genetic drift in place. In different regions, the variation may correspond well with language relationships, and probably constitutes differentiation which has been preserved over a considerable period, especially since the arrival of horticulture and development of village farming. However, none of this patterning suggests distinct waves of migration into Melanesia. Variation among Australian aboriginal groups is smaller, though far from absent. It may reflect a hunting culture together with social customs allowing more intertribal marriage than is typical of Melanesia. While phenotypically Australians and Melanesians differ, cranially they are closely allied, as against other major human groups. It is suggested that the genetic and phenotypic variety is old, that it existed in the previous home of the Australo-Melanesians (Old Melanesia, comprising present Indonesia and the Phillipines) at least back to 40,000 years ago, and that much of the variation in Melanesia and Australia, including their differences, results from the sampling process involved when different groups out of the original populations made early crossings of the water barriers from Old Melanesia.  相似文献   

8.
The techniques used by the Sanio-Hiowe of Papua New Guinea to produce edible starch from the sago palm (Metroxylon sp.) are described. Input-output analysis demonstrates that this is a highly productive subsistence technology; nevertheless, the Sanio-Hiowe economy is characterized by an absence of intensification. This is ascribed to functional consequences of dependence on hunting and gathering in the interior. In coastal and riverine habitats, other societies using sago supplemented by fishing or horticulture can more fully exploit the potential of sago as a basis for economic intensification and a more sedentary life.This field research among the Sanio-Hiowe of Yareno hamlet was carried out from March 1966 to August 1967 with the assistance of W. Townsend and the support of a National Science Foundation dissertation research grant and a United States Public Health Service Fellowship. In earlier publicationsHiowe was spelledHeve. I have altered the spelling of Sanio words to conform to the phonemic analysis of Lewis and Lewis (1970).  相似文献   

9.
Current attempts to increase the relevance of sociocultural anthropology encourage anthropologists to engage in the study of modernity. In this discourse dominated by sociologists, the contribution of anthropology is often to reveal cultural diversity in globalization, leading to the notion of multiple modernities. Yet such ethnographic accounts draw upon familiar sociological abstractions such as time-space compression, commodification, individualization, disenchantment, and reenchantment. This article shows how an underlying meta-narrative preempts social scientific argument by making shifts in analytical scales look natural, as in the alleged need to "situate" the particular in "wider" contexts. This analytical procedure undermines what is unique in the ethnographic method-its reflexivity, which gives subjects authority in determining the contexts of their beliefs and practices. Two ethnographic case studies are presented to support this argument, one from Melanesia on current interests in white people, money, and consumption and the other from Africa on born-again Christianity and individuality. The article ends by reflecting not only on the limits of metropolitan meta-narratives in returning relevance to anthropology but also on the contemporary conditions of academic work that undermine the knowledge practices of ethnography and render such meta-narratives plausible.  相似文献   

10.
A total of 171 plant species used by the Nishis, the Hill M iris, the Sulungs, and the Apatanis of Lower Subansiri district of Arunachal Pradesh in northeastern India; 12 animal species used by the Nishis were identified. Of the total plant species recorded 38% of the total were leafy vegetables and 28% were edible fruits. Others were used for food, liquor, medicine, household goods, traditional dresses, dyes, tattoos, fish and animal poisons, or for salt extraction. The Sulungs use starch obtained from the pith ofMetroxylon sagu as a staple food. The extensive use of wild plants and animals suggests that the tribes of northeastern India rely heavily on forest resources. The importance of conserving these in the light of rapid conversion of rainforests is emphasized.  相似文献   

11.
Breadfruit (Artocarpus altilis, Moraceae), a traditional starch crop in Oceania, has enjoyed legendary status ever since its role in the infamous mutiny aboard the H.M.S. Bounty in 1789, yet its origins remain unclear. Breadfruit's closest relatives are A. camansi and A. mariannensis. DNA fingerprinting data (AFLP, amplified fragment length polymorphisms) from over 200 breadfruit cultivars, 30 A. camansi, and 24 A. mariannensis individuals were used to investigate the relationships among these species. Multivariate analyses and the identification of species-specific AFLP markers indicate at least two origins of breadfruit. Most Melanesian and Polynesian cultivars appear to have arisen over generations of vegetative propagation and selection from A. camansi. In contrast, most Micronesian breadfruit cultivars appear to be the result of hybridization between A. camansi-derived breadfruit and A. mariannensis. Because breadfruit depends on humans for dispersal, the data were compared to theories on the human colonization of Oceania. The results agree with the well-supported theory that humans settled Polynesia via Melanesia. Additionally, a long-distance migration from eastern Melanesia into Micronesia is supported.  相似文献   

12.
About seven percent of the annual American potato crop, or 25,000,000 bushels, is converted into potato starch by 21 factories in Maine and six in Idaho, with a combined capacity of annually producing about 150,000,000 pounds of starch, used principally in sizing textiles but also in the manufacture of paper, food products and adhesives.  相似文献   

13.
Potato pulp is a high-volume, low-value byproduct stream resulting from the industrial manufacture of potato starch. The pulp is a rich source of biologically functional dietary fibers, but the targeted valorisation of the fibers requires removal of the residual starch from the pulp. The objective of this study was to release the residual starch, making up 21–22% by weight of the dry matter, from the potato pulp in a rational way employing as few steps, as few enzyme activities, as low enzyme dosages, as low energy input (temperature and time), and as high pulp dry matter as possible. Starch removal to obtain dietary fibers is usually accomplished via a three step, sequential enzymatic treatment procedure using a heat stable α-amylase, protease, and amyloglucosidase. Statistically designed experiments were performed to investigate the influence of enzyme dose, amount of dry matter, incubation time and temperature on the amount of starch released from the potato pulp. The data demonstrated that all the starch could be released from potato pulp in one step when 8% (w/w) dry potato pulp was treated with 0.2% (v/w) (enzyme/substrate (E/S)) of a thermostable Bacillus licheniformis α-amylase (Termamyl® SC) at 70 °C for at least 65 min. The study also indicated that the amount of other carbohydrates released from the pulp during the release of starch was less than using the AOAC Official Method 985.29 and another recently published starch release method employed as a pretreatment for enzymatic upgrading of a pectinaceous potato pulp fiber.  相似文献   

14.
Red algae are widely known to produce floridean starch but it remains unclear whether the molecular structure of this algal polyglucan is distinct from that of the starch synthesized by vascular plants and green algae. The present study shows that the unicellular species Porphyridium purpureum R-1 (order Porphyridiales, class Bangiophyceae) produces both amylopectin-type and amylose-type alpha-polyglucans. In contrast, Cyanidium caldarium (order Porphyridiales, class Bangiophyceae) synthesizes glycogen-type polyglucan, but not amylose. Detailed analysis of alpha-1,4-chain length distribution of P. purpureum polyglucan suggests that the branched polyglucan has a less ordered structure, referred to as semi-amylopectin, as compared with amylopectin of rice endosperm having a tandem-cluster structure. The P. purpureum linear amylose-type polyglucan, which has a lambda(max) of 630 nm typical of amylose-iodine complex and is resistant to Pseudomonas isoamylase digestion, accounts for less than 10% of the total polyglucans. We produced and isolated a cDNA encoding a granule-bound starch synthase (GBSS)-type protein of P. purpureum, which is probably the approximately 60-kDa protein bound tightly to the starch granules, resembling the amylose-synthesizing GBSS protein of green plants. The present investigation indicates that the class Bangiophyceae includes species producing both semi-amylopectin and amylose, and species producing glycogen alone.  相似文献   

15.
A population sample from the Milne Bay district of Papua-New Guinea was found to have extremely high pattern intensity indices and total ridge-counts. These fell into the range of certain Australian Aboriginal tribes, and so argue for a possible connection between this region of Melanesia and the Australian Aborigines, although equally strong connections with other regions of Melanesia are known.  相似文献   

16.
Skin and hair pigmentation are two of the most easily visible examples of human phenotypic variation. Selection-based explanations for pigmentation variation in humans have focused on the relationship between melanin and ultraviolet radiation, which is largely dependent on latitude. In this study, skin and hair pigmentation were measured as the melanin (M) index, using narrow-band reflectance spectroscopy for 1,135 individuals from Island Melanesia. Overall, the results show remarkable pigmentation variation, given the small geographic region surveyed. This variation is discussed in terms of differences between males and females, among islands, and among neighborhoods within those islands. The relationship of pigmentation to age, latitude, and longitude is also examined. We found that male skin pigmentation was significantly darker than females in 5 of 6 islands examined. Hair pigmentation showed a negative, but weak, correlation with age, while skin pigmentation showed a positive, but also weak, correlation with age. Skin and hair pigmentation varied significantly between islands as well as between neighborhoods within those islands. Bougainvilleans showed significantly darker skin than individuals from any other island considered, and are darker than a previously described African-American population. These findings are discussed in relation to prevailing hypotheses about the role of natural selection in shaping pigmentation variation in the human species, as well as the role of demographic processes such as admixture and drift in Island Melanesia.  相似文献   

17.
It has been found in this work that the starchiness and starch content in tubers of GM potato and tubers of initial Lugovskoi potato variety are identical. No differences and difficulties were observed upon starch preparation from GM and common potato. Starch samples isolated from GM potato conform to the current standard for potato starch. The starch isolated from GM potato has a higher melting point, i.e., it is more thermally stable as compared with the starch isolated from a control sample. The bulk modulus of gels obtained from starch isolated from GM potato is higher in comparison with that of gels prepared from starch isolated from the control sample. Thermodynamic and rheological properties of starch from GM potato provide a possibility to predict its application in the manufacture of thermostable and strong polymeric materials.  相似文献   

18.
The major isoform of starch synthase from the soluble fraction of developing potato tubers has been purified and used to prepare an antibody and isolate a cDNA. The protein is 140 kD, and it is distinctly different in predicted primary amino acid sequence from other isoforms of the enzyme thus far described. Immunoinhibition and immunoblotting experiments and analysis of tubers in which activity of the isoform was reduced through expression of antisense mRNA revealed that the isoform accounts for approximately 80% of the activity in the soluble fraction of the tuber and that it is also bound to starch granules. Severe reductions in activity had no discernible effect on starch content or amylose-to-amylopectin ratio of starch in tubers. However, they caused a profound change in the morphology of starch granules, indicative of important underlying changes in the structure of starch polymers within the granule.  相似文献   

19.
The human leukocyte antigen (HLA) distributions in 16 Pacific populations have been collated from published and unpublished reports. Gene frequency and linkage disequilibrium relationships among groups show that Australians and Papuans share a common ancestry, that coastal Melanesia has about 16% Austronesian admixture, and that Fiji is truly intermediate between Melanesia and Polynesia. In Polynesia, Cook Islanders show closer affinity with populations of Western Polynesia than with Maoris and Easter Islanders, in contrast to their linguistic affiliations, but otherwise HLA distributions show a clear division between the populations of Eastern and Western Polynesia. This study emphasizes the contribution the HLA system can make to anthropological studies and has provided a version of colonization of the Pacific compatible with theories based on prodigious efforts in many disciplines.  相似文献   

20.
The human settlement of the Pacific Islands represents one of the most recent major migration events of mankind. Polynesians originated in Asia according to linguistic evidence or in Melanesia according to archaeological evidence. To shed light on the genetic origins of Polynesians, we investigated over 400 Polynesians from 8 island groups, in comparison with over 900 individuals from potential parental populations of Melanesia, Southeast and East Asia, and Australia, by means of Y chromosome (NRY) and mitochondrial DNA (mtDNA) markers. Overall, we classified 94.1% of Polynesian Y chromosomes and 99.8% of Polynesian mtDNAs as of either Melanesian (NRY-DNA: 65.8%, mtDNA: 6%) or Asian (NRY-DNA: 28.3%, mtDNA: 93.8%) origin, suggesting a dual genetic origin of Polynesians in agreement with the "Slow Boat" hypothesis. Our data suggest a pronounced admixture bias in Polynesians toward more Melanesian men than women, perhaps as a result of matrilocal residence in the ancestral Polynesian society. Although dating methods are consistent with somewhat similar entries of NRY/mtDNA haplogroups into Polynesia, haplotype sharing suggests an earlier appearance of Melanesian haplogroups than those from Asia. Surprisingly, we identified gradients in the frequency distribution of some NRY/mtDNA haplogroups across Polynesia and a gradual west-to-east decrease of overall NRY/mtDNA diversity, not only providing evidence for a west-to-east direction of Polynesian settlements but also suggesting that Pacific voyaging was regular rather than haphazard. We also demonstrate that Fiji played a pivotal role in the history of Polynesia: humans probably first migrated to Fiji, and subsequent settlement of Polynesia probably came from Fiji.  相似文献   

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