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1.
We surveyed the material collected for fungus culturing by attine ants in the cerrado vegetation of southeast Brazil. Six genera of the so-called lower attines (Cyphomyrmex, Mycetarotes, Mycocepurus, Myrmicocrypta, Sericomyrmex and Trachymyrmex) collect a wide variety of plant material as fungal substrate. Plant diaspores of nonmyrmecochorous species comprise a large portion of the items brought to the nest, especially in the rainy season. Removal experiments using fruits of selected plant species revealed that attine ants (including the leaf-cutters Atta and Acromyrmex) not only actively clean the seeds (remove fruit pulp), but also carry them up to 12 m in the cerrado. Germination tests showed that removal of fruit pulp by attine ants increases germination rate in Ocotea pulchella (Lauraceae), Prunus sellowii (Rosaceae), Ouratea spectabilis (Ochnaceae), Rapanea umbellata (Myrsinaceae) and Psychotria stachyoides (Rubiaceae). For P. stachyoides, however, ants had no effect on germination if seeds had already passed the digestive tract of birds. Aril removal by attines also increases germination success of Copaifera langsdorffii (Leguminosae) and Virola sebifera (Myristicaceae) seeds. The results indicate that attine-fruit/seed interactions are particularly conspicuous in the cerrado, suggesting that fungus-growing ants may play a relevant role in fruit/seed biology in this vegetation type. Potential ant-derived benefits to diaspores of nonmyrmecochorous plants in the cerrado would include secondary seed dispersion and/or increased germination success by ant-handled seeds.  相似文献   

2.
We examined the interspecific variations in intensity of total abiotic (chemical and physical) defenses in five sympatric Macaranga (Euphorbiaceae) species, including three myrmecophytic species. The intensity of the total abiotic defense for each Macaranga species was estimated by measuring inhibiting effects on the growth performance of the common cutworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) when the cutworm larvae were fed fresh leaves of each Macaranga species. Indices of the growth performance, number of dead larvae, pupal weight and length of larval period were obtained. We found that the intensities of total abiotic defense of the two non-myrmecophytic species were significantly stronger than those of the three myrmecophytic species, and that there was a significant difference in intensity even within the three myrmecophytic species. The former result supports the hypothesis that, unlike non-myrmecophytic species, myrmecophytic species cannot invest so many metabolic resources in abiotic defense, because they have to allocate nutrients to biotic defense (toward biotic defense agents). Moreover, the latter result suggests the possibility that the three sympatric myrmecophytes have different defense strategies, with a trade-off between abiotic and biotic defense, and/or with a trade-off between defense and other life-history traits such as growth and reproduction. Abiotic defense can be roughly separated into physical and chemical mechanisms. To assess the intensity of the physical defense of Macaranga leaves, we measured the leaf toughness of each species. In addition, to assess the intensity of the plants general chemical defense, cutworm larvae were reared on an artificial diet containing dry leaf powder of each Macaranga species, and their growth performances were compared. The estimated orders of intensity of both leaf toughness and general chemical defense coincided with that of the total abiotic factors measured by the growth performance of cutworm on fresh leaves. This suggests the presence of both physical defenses, represented by leaf toughness, and a general chemical defense affecting the intensity of the total abiotic defense in similar ways.  相似文献   

3.
Summary Random genomic probes were used to detect restriction fragment length polymorphisms (RFLPs) in 26 accessions of Musa representing eight species from Papua New Guinea (PNG), M. textilis, M. jackeyi and one accession of Ensete. Ninety-eight phylogenetically informative characters were scored and analyzed cladistically and phenetically. Results generally agreed with previous morphology-based phylogenetic analyses. However, the closest wild relative of the edible M. fehi (fe'i banana) appears to be M. lolodensis. Musa angustigemma is sister species with M. boman and M. jackeyi and is distinct from M. peekelii, with which it is often united. Musa boman is unambiguously placed in section Australimusa. The diploid parthenocarpic landraces of section Musa unique to PNG are closely related to, but apparently distinct from, M. acuminata ssp. banksii. The evolution of the fe'i bananas and the M. acuminata-derived diploid landraces of PNG are discussed.  相似文献   

4.
Growth patterns of populations in Papua New Guinea (PNG) have traditionally shown considerable variation, with the greatest difference lying between coastal and highland populations. While genetic differences in explaining these patterns cannot be excluded, the generally poor growth relative to western growth references is largely due to the complex interactive effects of undernutrition and infection. The effects of diet, nutrition and infection on the nutritional status of a child vary with age, the general disease ecology and the type and extent of exposure to it, patterns of infant and young child feeding, and types of food consumed. There are two possible ways in which the relationship between undernutrition and infection can begin; one in which poor nutritional status leads to impaired immunocompetence and reduced resistance to infection, and the other in which exposure to infectious disease can lead to a range of factors that reduce food intake, absorption of nutrients, or increase nutrient requirements. In PNG prior to, and at early stages of modernisation, primary malnutrition is likely to have been the usual initiating factor in the onset of growth faltering due to undernutrition-infection interactions. However, the possibility that infection may have been the initiating event in some societies cannot be excluded. This would have happened by way of early dietary supplementation of infants with foods of minor nutritional significance, which could have acted as a vehicle for the introduction of infectious disease to the child. With modernisation and adoption of primary health care principles, earlier supplementation of infant diet than was previously the case became common in PNG. This has lead to general improvements in growth and nutritional status. However, in populations where undernutrition is still common, infection has become more important than primary malnutrition as the initiator of growth faltering due to undernutrition-infection interactions.  相似文献   

5.
6.
This paper examines the relationship between ‘subsistence’ production, simple commodity production and wage labour and the different effects this relationship has on males and females. The peri-urban village of Siar, located a few kilometres north of Madang town in Papua New Guinea, is used as a case study. It is argued that the village as a social group is dependent on wage labour for its reproduction and hence is proletarianized. As part of the proletarianization process, married women in the village have become doubly subordinated: to capital and to men.  相似文献   

7.
This paper explores the nature of grief in Lihir, Papua New Guinea, in light of psychological theories of bereavement and grief. Anthropologists have demonstrated that culture has an impact on both the expression and experience of grief and can offer both a challenge to established theories and new perspectives on the conceptualisations and experiences of the bereaved. Until recently, ‘grief work’ was the foremost model for understanding bereavement as a psychological process and was also used by anthropologists in cross‐cultural work. However, since the 1990s, a number of alternative models of normal grief have emerged, including the dual process coping model and the model that proposes resilience as a central concept. These newer models, particularly the one which incorporates resilience, offer more for understanding grief in Lihir. The article argues that grief in Lihir has a phase of sorrow and worry that is dealt with through the sociality and activity of the mourning period, and then a longer phase of active remembering and forgetting of the deceased. The social and cultural context of bereavement is not adequately captured in current psychological conceptualisations of social support, which need to be broadened to encompass cross‐cultural material.  相似文献   

8.
9.
Ant–plant relationships, with variability in both intimacy and the trophic structure of associations, are described for the Austro-Malesian rainforest tree genus Ryparosa (Achariaceae). The range of associations involves opportunistic interactions between plants and foraging ants, mediated by food bodies, and tighter associations in which ant colonies, tending hemipteran trophobionts, reside permanently in plant structures with different degrees of adaptation to house ants. Our study provides strong baseline data to suggest that Ryparosa could become a new model system for examining the evolutionary radiation of ant-related traits. To define the diversity of ant–plant associations in Ryparosa , we first present a review of ant-plant terminology and an outline of its use in this study. Field studies of ant interactions with food bodies in myrmecotrophic R. kurrangii from Australia and the association between myrmecoxenic R. fasciculata and two Cladomyrma plant-ant species on the Malay Peninsula provide detailed examples of ant–plant interactions. An examination of herbarium material revealed a diverse range of ant–plant associations in other Ryparosa taxa. All 27 species had evidence of food body production, seven species had evidence of stem inhabitation by ants, five species had specialized stem domatia, and the domatia of R. amplifolia featured prostomata. Variation in the specificity of Ryparosa ant–plant interactions is discussed in relation to known ant partners and other ant–plant associations.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 353–371.  相似文献   

10.
Ryan Schram 《Ethnos》2013,78(4):447-470
There is a growing consensus that money and the market principle have not led to a great transformation into modernity. Rather, market exchange is everywhere socially embedded. But what does this embedding consist of, structural limits, tactics of resistance, or moral boundaries? Auhelawa (Normanby Island, Papua New Guinea) have incorporated money into their local economy in a variety of ways which keep the logic of the market in check. The comparison between two modes of accumulation – business and charity – sheds light on the precise nature of embeddedness. Local entrepreneurs describe themselves as navigating dilemmas which arise from contradictions between accumulation and reciprocity. Church congregations, however, appear to have transcended this conflict by representing their charitable contributions of money as love-gifts which are not subject to reciprocity. While charity, like business, is an embedded form of accumulation, I argue that it creates links to an alternative hierarchy of values, and thus contains the potential to create a great transformation of its own.  相似文献   

11.
The links between gender, sexuality and violence hold serious implications for HIV transmission and its social and economic effects. In Papua New Guinea, enduring and pervasive patterns of male sexual behaviour involving coercion, violence and gang rape are highly conducive to the transmission of HIV and other sexually transmitted infections and have a critical bearing on women's sexual autonomy and health. The realities of violence are intensified by the widespread view that women are responsible for the spread of the virus. This paper engages the theme of mobility to consider the fluid and dynamic character of gender relations and sexuality in contemporary Papua New Guinea, and to gain perspective on constructions of modern masculinity and the discursive representations of gender violence in the context of the escalating HIV epidemic.  相似文献   

12.
Class I HLA gene frequencies show considerable variation over short geographical distances in Papua New Guinea. Hypotheses to account for this invoke natural selection, population structure, the pattern of population movement, or past demographic changes. To determine the role of the various factors in shaping this distribution, we have studied correlations between HLA-based genetic distances, geographical distances, altitude, and linguistic differences in Papua New Guinea. Linguistic differences at the family or stock level within the Trans-New Guinea Phylum generally correspond to genetic differences. However, on the basis of their HLA gene frequencies, speakers of Austronesian (AN) languages do not form a distinct group of populations. Linguistic variation and spatial autocorrelation do not fully account for the altitudinal cline differences noted in gene frequencies, particularly at the HLA-A locus. We propose that the distribution of HLA gene frequencies in Papua New Guinea is partially under the control of selection operating differentially along the altitude gradient. © 1994 Wiley-Liss, Inc.  相似文献   

13.
Taking the example of the tubuan masked figure, an art form of New Ireland, I explore recent theoretical debates on the question of meaning in art. Challenging approaches that privilege the semiotic, I argue that this form of art is more appropriately seen as a revelation of power. The tubuan brings forth the concealed efficacy, capacities and intentionality of the producer, which elicit responses from, or act upon, the audience in various negative or positive ways. This art object is a form of disclosure in itself, and thus speaks for itself. The appreciation of this art is not a matter of cerebral contemplation, the unearthing of ideas and the translation of images into verbal form, but in an embodied form that is experienced directly as affect. I take seriously the embodied nature of social action, of which the production of art is one form.  相似文献   

14.
Food Rules: Hunting, Sharing, and Tabooing Game in Papua New Guinea. Harriet Whitehead. Ann Arbor: University of Michigan Press, 2000. 330 pp.  相似文献   

15.
16.
The role of introduced epidemic disease in highland New Guinea is considered in light of recent debate concerning pre-contact adaptations. Seroepidemiological studies of the Hagahai, a small isolated group of hunterhorticulturalists in the fringe highlands of Papua New Guinea, document the recent introduction of mumps, hepatitis B, specific types of influenza, and rotavirus. Results are related to ethnographic findings, detailing past levels of intergroup contact and recent changes in settlement patterns, travel, feasting, health care, and other cultural factors. Data suggest that intergroup disease transmission is greatly increased decades before officially recorded time of contact and that mortality levels documented soon thereafter are not indicative of the pre-contact adaptation.  相似文献   

17.
Enumeration of a one hectare plot at 900 m a.s.l in Papua New Guinea revealed 693 individuals of 228 tree and liana species ≥ 10 cm DBH. A 0.1 hectare subplot contained 302 individuals of 106 species 2.5 ≥ DBH < 10 cm. Lauraceae, Moraceae, and Myristicaceae were the most important families in both size classes. This site is very diverse compared with other tropical forests, and like other species-rich sites worldwide, it has high aseasonal rainfall and high rates of natural disturbance.  相似文献   

18.
Evidence is presented that female Anopheles farauti Laveran released in an alien village dispersed more, in their first oviposition cycle after release, than females released in their village of capture. In a subsidiary experiment transporting the mosquitoes did not affect dispersal; wind speed or direction was not sufficient to account for the phenomenon. It is hypothesized that these permanent-pool breeding mosquitoes make appetitive long-range flights to oviposition sites. Mosquitoes blood-fed before midnight had a shorter oviposition cycle than those fed just before dawn. Nulliparous females, and those with well-defined ovariolar dilatations, predominated in the early evening whereas females that had oviposited recently were largely collected in the middle and later parts of the night.  相似文献   

19.
This study focused on the suitability of four species of cereal stem borers for the development of five geographic populations of Cotesia sesamiae (Cameron). C. sesamiae, an indigenous larval parasitoid of gramineous stem borers, is widespread in Africa. Four stem borers, Chilo partellus (Swinhoe), Chilo orichalcociliellus Strand (Lepidoptera: Crambidae), Busseola fusca Fuller, and Sesamia calamistis Hampson (Lepidoptera: Noctuidae), were offered to C. sesamiae for oviposition. Parasitoid individuals originated from five locations in Kenya. Biological parameters such as developmental time, percentage parasitism, progeny production, mortality of immature parasitoids, and proportion of female progeny were compared across host species. The two populations from western Kenya developed well on B. fusca. However, populations from the coast and the Eastern Province could not successfully parasitize B. fusca. With the exception of B. fusca, the percentage of hosts successfully parasitized by the different C. sesamiae populations was not different. The size of the host appeared to be an important factor influencing the development and reproductive potential of the parasitoid. We conclude that the different parasitoid populations were adapted to location-specific characteristics. Parasitoid–host compatibility must be evaluated before release for better establishment and colonization.  相似文献   

20.
This paper discusses large‐scale genealogical work at three projects in Papua New Guinea, West Papua and Australia and considers three questions: in what respects is genealogy intellectual property (IP) and, if so, who owns it; what were the regimes of permissions that permitted the collection of genealogical knowledge in each of the three cases; and what duty of care do collectors/curators of genealogical knowledge have in respect of preservation and safeguarding against improper use? It is argued that a new form of ‘emergent’ knowledge arises in which intellectual property rights (IPR) are unclear. What is more certain is that anthropologists owe a ‘cultural heritage duty of care’ towards genealogical information. The key criterion is that anthropologists must be in a position, and allowed by those who employ them, to guarantee ‘unbroken oversight’ of genealogical materials regardless of what media they are on or how they are stored.  相似文献   

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