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1.
The evolution of human phenotypic plasticity: age and nutritional status at maturity 总被引:1,自引:0,他引:1
Gage TB 《Human biology; an international record of research》2003,75(4):521-537
Several evolutionary optimal models of human plasticity in age and nutritional status at reproductive maturation are proposed and their dynamics examined. These models differ from previously published models because fertility is not assumed to be a function of body size or nutritional status. Further, the models are based on explicitly human demographic patterns, that is, model human life-tables, model human fertility tables, and, a nutrient flow-based model of maternal nutritional status. Infant survival (instead of fertility as in previous models) is assumed to be a function of maternal nutritional status. Two basic models are examined. In the first the cost of reproduction is assumed to be a constant proportion of total nutrient flow. In the second the cost of reproduction is constant for each birth. The constant proportion model predicts a negative slope of age and nutritional status at maturation. The constant cost per birth model predicts a positive slope of age and nutritional status at maturation. Either model can account for the secular decline in menarche observed over the last several centuries in Europe. A search of the growth literature failed to find definitive empirical documentation of human phenotypic plasticity in age and nutritional status at maturation. Most research strategies confound genetics with phenotypic plasticity. The one study that reports secular trends suggests a marginally insignificant, but positive slope. This view tends to support the constant cost per birth model. 相似文献
2.
Esther J. Lee George Koki D. Andrew Merriwether 《American journal of physical anthropology》2010,142(4):613-624
Situated along a corridor linking the Asian continent with the outer islands of the Pacific, Papua New Guinea has long played a key role in understanding the initial peopling of Oceania. The vast diversity in languages and unique geographical environments in the region have been central to the debates on human migration and the degree of interaction between the Pleistocene settlers and newer migrants. To better understand the role of Papua New Guinea in shaping the region's prehistory, we sequenced the mitochondrial DNA (mtDNA) control region of three populations, a total of 94 individuals, located in the East Sepik Province of Papua New Guinea. We analyzed these samples with a large data set of Oceania populations to examine the role of geography and language in shaping population structure within New Guinea and between the region and Island Melanesia. Our results from median‐joining networks, star‐cluster age estimates, and population genetic analyses show that while highland New Guinea populations seem to be the oldest settlers, there has been significant gene flow within New Guinea with little influence from geography or language. The highest genetic division is between Papuan speakers of New Guinea versus East Papuan speakers located outside of mainland New Guinea. Our study supports the weak language barriers to genetic structuring among populations in close contact and highlights the complexity of understanding the genetic histories of Papua New Guinea in association with language and geography. Am J Phys Anthropol 142:613–624, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
3.
Summary Four new G6PD variants have been characterized in individuals from Papua New Guinea. This study demonstrates that the previously reported Markham variant and the newly characterized Salata variant may be widely distributed in Papua New Guinea. The data presented here together with those of previously published studies demonstrate a degree of heterogeneity of G6PD deficiency that is much higher than that in other regions of the world where G6PD deficiency is common. 相似文献
4.
Contributions to the Cladocera fauna from Papua New Guinea 总被引:1,自引:1,他引:0
Twenty-eight taxa of the Cladocera are identified in collections from Papua New Guinea, 17 being new records for New Guinea,
bringing the total number of Cladocera taxa reported for this region to 39. Most of the taxa are circumtropical. One species
(Sarsilatona papuana) is endemic to Papua New Guinea and northern Australia. The species list includes two species that are normally listed as
Holarctic:Alonella nana andAlona rustica. Widespread genera such asDaphnia, Pleuroxus, Disparalona, Acroperus were strikingly absent from the Papua New Guinean material. 相似文献
5.
The Industrial Revolution ushered in a rapid transition from agriculture to industrialization. Some biological effects of this transition included increasing life expectancy, reduced infant mortality, and some decline in fertility. Reduced infant mortality first brought about an increase in life expectancy, but as humans were able to control infectious diseases, child and adult mortality also decreased. Now, accidents and chronic diseases are responsible for most mortality in many age groups. This shift from infectious diseases to accidents and chronic diseases is called the health transition. Japan and US are Pacific Basin countries which have relatively high life expectancy and low infant mortality (1988, 75.54 years vs. 71.38 years, and 4.4 vs. 9.9, respectively). These figures suggest that these countries rather advanced in the health transition. Japan may have better life expectancy than the US because of the effect of environmental factors, ethnic diversity, and health care differentials by social class on cardiovascular disease and cancer mortality. China and Thailand hold intermediate positions (67.98 years (1985-1990) vs. 63.82 years (1985-1986), and 32.4 vs. 39, respectively). Some research indicates that urban conditions and factory work increase the cardiovascular disease risk among the Chinese. Recent research suggests that access to immunization and modern medical care for acute disease are the only critical variables of the health transition rather than other variables. Papua New Guinea is not progressing very well (53.18 years and 58). Papua New Guinea has not yet been able to control infectious diseases, especially malaria. This comparison illustrates that populations progress through the health transition at different rates. 相似文献
6.
Mating tests among strains of Lentinula edodes distributed in Asia-Australasia were conducted. As a result, 26 strains were classified into three groups: 2 strains from
Mt. Wilhelm in Papua New Guinea (PN1 group) showed intersterility with 7 strains from Mt. Albert Edward and Mt. Kaisenik in
Papua New Guinea (PN2 group) and semicompatibility (clamp formation restricted to contact zone between paired monokaryons)
with 17 strains from Asia-Australasia (AA group), whereas the strains of the PN2 group showed compatibility with the AA group.
These results suggest that the shiitake populations distributed in Asia-Australasia including Papua New Guinea are in the
process of speciation.
Contribution no. 391 from the Tottori Mycological Institute 相似文献
7.
《Lichenologist (London, England)》1993,25(2):121-135
Abstract: The new lichen genus Musaespora is described from Java and Papua New Guinea. It is the first known pyrenocarpous lichen genus with campylidia, and appears to belong to the Aspidotheliaceae. Three species are described, two foliicolous species from Papua New Guinea and one corticolous species from Java. In addition, a list is given of the foliicolous lichen flora of the site in Papua New Guinea, where the foliicolous Musaespora species have been found, two more new foliicolous species are described, Echinoplaca hispida and Sporopodium lucidum, and 19 species are recorded for the first time form Papua New Guinea. 相似文献
8.
Abstract. A study was undertaken to assess the impact of the strepsipteran endoparasite Stichotrema dallatorreanum Hofeneder on the performance of its host Segestidea novaeguineae (Brancsik), a tettigoniid pest of oil palm in Papua New Guinea. This involved analyses of morphology, gut contents, body composition and reproductive variables of field-collected adults of stylopized and unstylopized hosts. The morphological consequences of stylopization by S. dallatorreanum included reduced wing, ovipositor and digestive tract lengths, whereas antennal length was largely unaffected. Feeding activity by the host, as estimated indirectly through weighing gut contents, was significantly reduced in parasitised female hosts, whereas smaller males showed no effect. Parasitized hosts had a reduced carcass dry weight associated with reduced nitrogen content and a substantial decline in carcass lipid content. Host reproductive variables were profoundly affected by stylopization. In females this included impaired ovarian development, reduced egg number and gonadal weight, the last of which was also reduced in males. There was an association between the number of S. dallatorreanum present (maximally six in males and nine in females) within a host and the extent of the impact of stylopization on most of the host characters investigated. The ability of S. dallatorreanum to reduce feeding and reproduction in the host suggests it may have potential use as a bio-control agent in the management of tettigoniid pests in Papua New Guinea. 相似文献
9.
Describing the drivers of species loss and of community change are important goals in both conservation and ecology. However, it is difficult to determine whether exploited species decline due to direct effects of harvesting or due to other environmental perturbations brought about by proximity to human populations. Here we quantify differences in species richness of coral reef fish communities along a human population gradient in Papua New Guinea to understand the relative impacts of fishing and environmental perturbation. Using data from published species lists we categorize the reef fishes as either fished or non-fished based on their body size and reports from the published literature. Species diversity for both fished and non-fished groups decreases as the size of the local human population increases, and this relationship is stronger in species that are fished. Additionally, comparison of modern and museum collections show that modern reef communities have proportionally fewer fished species relative to 19th century ones. Together these findings show that the reef fish communities of Papua New Guinea experience multiple anthropogenic stressors and that even at low human population levels targeted species experience population declines across both time and space. 相似文献
10.
Eight species of the Strongylophthalmyiidae are reported from Papua New Guinea. Of these, five species (Strongylophthalmyia gigantica sp. nov., S. papuana sp. nov., S. rubella sp. nov., S. sedlaceki sp. nov. and S. shatalkini sp. nov.) are described as new to science. Strongylophthalmyia puncticollis Frey is recorded for the first time from Papua New Guinea. Faunistic remarks, a key to the species of the Strongylophthalmyia in Papua New Guinea and a world checklist are provided. 相似文献
11.
We have tested the hypothesis that the abnormal development of the central nervous system seen in endemic cretinism might be accompanied by concurrent abnormal dermatoglyphic patterns. We compared digital and palmar dermatoglyphics of normal individuals and endemic cretins inhabiting the Huon Peninsula of Papua New Guinea. The population sampled from the Irumu River Valley included 118 males and 114 females with 22 male cretins and 23 female cretins. The population sampled from the Wantoat River Valley included 72 males and 38 females with 12 male cretins. No pathognomonic patterns were found that could identify the endemic cretin subpopulation. However, the occurrence of a number of differences between controls and cretins suggests that subtle changes in dermatoglyphic patterns accompany the anomalous development of the CNS secondary to maternal iodine deficiency. We discuss the significance of these findings and compare the dermatoglyphic patterns of normal Irumu and Wantoat natives and 21 other populations of Papua New Guinea. 相似文献
12.
Peter D. Dwyer 《Human ecology: an interdisciplinary journal》1983,11(2):145-174
Analyses of nearly 3000 hr of hunting for mammals by Etolo people of Papua New Guinea reveal that older hunters were more successful than younger hunters, that increased success was due, in large part, to higher rates of capture for only two of 24 prey species, and that access to a good hunting dog accounted for the increase in rate of capture for one of these two species. A comparison of Gadio Enga and Rofaifo mammal hunting with that of Etolo reveals a marked decline in energy and protein yields with increase of altitude. This is attributed to altitudinal changes in the composition of the available fauna within Papua New Guinea and to reinforcing effects from increased human population density. 相似文献
13.
The metabolism of New Guinean pteropodid bats 总被引:1,自引:1,他引:0
McNab BK Bonaccorso FJ 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2001,171(3):201-214
Rate of metabolism and body temperature were measured in eight species of pteropodid bats that live in Papua New Guinea. These data and those from 13 other species available in the literature are examined to determine the factors with which the energetics of pteropodids are correlated. Lowland populations of species that weigh < 35 g generally have low basal rates and often become torpid, whereas their highland populations had standard or high basal rates and were precise thermoregulators, as were all adult pteropodids that weighed more than 60 g. In large pteropodids belonging to the genera Dobsonia and Pteropus, females are smaller and consequently have lower total basal rates than males. Compared to species found on continents and large islands, species limited in distribution to small islands have lower basal rates, both because of a smaller mass and a reduction of metabolism independent of body mass. These trends are most marked in females that belong to small-island species, adjustments that may facilitate reproduction and survival on small oceanic islands with a limited resource base. Minimal thermal conductances are usually low in species that roost exposed in trees, whereas large species that roost in caves have either standard or high conductances. 相似文献
14.
Patricia Lyons Johnson 《Human ecology: an interdisciplinary journal》1990,18(4):403-416
The European demographic transition of the nineteenth century is often proposed as a model for demographic change in twentieth century developing nations, and economic development is seen as leading to an inevitable reduction in total fertility in these nations. This paper examines data from the Gainj of Papua New Guinea, a natural fertility population with very low reproductive output, and suggests that the effects of development on fertility change are much more complex than a simple demographic transition model would suggest. Looking at two variables known to contribute significantly to low total fertility among the Gainj, late age at first birth for women and long interbirth intervals, the paper suggests that households, in their recruitment and allocation of labor, may exert a mediating influence in the relationship between economic development and fertility. 相似文献
15.
Fred Kraus 《ZooKeys》2013,(333):93-121
I describe three new species of the diverse microhylid frog genus Oreophryne from Papua New Guinea. Two of these occur in two isolated mountain ranges along the northern coast of Papua New Guinea; the third is from Rossel Island in the very southeasternmost part of the country. All three are the first Oreophryne known from these areas to have a cartilaginous connection between the procoracoid and scapula, a feature usually seen in species far to the west or from the central cordillera of New Guinea. Each of the new species also differs from the many other Papuan Oreophryne in a variety of other morphological, color-pattern, and call features. Advertisement-call data for Oreophryne species from the north-coast region suggest that they represent only two of the several call types seen in regions further south, consistent with the relatively recent derivation of these northern regions as accreted island-arc systems. The distinctively different, whinnying, call type of the new species from Rossel Island occurs among other Oreophryne from southeastern Papua New Guinea but has been unreported elsewhere, raising the possibility that it may characterize a clade endemic to that region. 相似文献
16.
From 1960 to 1979 total annual consumption of tobacco in Papua New Guinea increased from 573 to 1800 metric tonnes. The annual consumption of tobacco per head increased from 2.78 to 6.14 kg, and the proportion of commercial cigarettes smoked is estimated to have increased from 20% to 71% of the total tobacco consumption. Between 1965 and 1979 the average annual age standardised incidence of reported cases of carcinoma of the oral cavity increased significantly in women (p less than 0.01) but not in men (p greater than 0.05). This rise might have been related to increasing consumption of tobacco or alcohol, or both, in individuals who habitually chewed betel nut. There was no significant change in the reported incidences of carcinoma of the larynx, lung, oesophagus, pancreas, kidney, or bladder. At present there are no constraints on the marketing of tobacco in Papua New Guinea. 相似文献
17.
Summary A total of 362 males from various regions of Papua New Guinea were screened for red cell glucose-6-phosphate dehydrogenase (G6PD) activity. Twenty-six G6PD deficient individuals were identified. Biochemical characterization of G6PD purified from these subjects has revealed 13 new variants and several copies of previously described forms of G6PD. This study illustrates the extreme heterogeneity of G6PD deficiency among the people of Papua New Guinea. 相似文献
18.
Phil L. Shearman Julian Ash Brendan Mackey Jane E. Bryan Barbara Lokes 《Biotropica》2009,41(3):379-390
Quantifying forest change in the tropics is important because of the role these forests play in the conservation of biodiversity and the global carbon cycle. One of the world's largest remaining areas of tropical forest is located in Papua New Guinea. Here we show that change in its extent and condition has occurred to a greater extent than previously recorded. We assessed deforestation and forest degradation in Papua New Guinea by comparing a land-cover map from 1972 with a land-cover map created from nationwide high-resolution satellite imagery recorded since 2002. In 2002 there were 28,251,967 ha of tropical rain forest. Between 1972 and 2002, a net 15 percent of Papua New Guinea's tropical forests were cleared and 8.8 percent were degraded through logging. The drivers of forest change have been concentrated within the accessible forest estate where a net 36 percent were degraded or deforested through both forestry and nonforestry processes. Since 1972, 13 percent of upper montane forests have also been lost. We estimate that over the period 1990–2002, overall rates of change generally increased and varied between 0.8 and 1.8 percent/yr, while rates in commercially accessible forest have been far higher—having varied between 1.1 and 3.4 percent/yr. These rates are far higher than those reported by the FAO over the same period. We conclude that rapid and substantial forest change has occurred in Papua New Guinea, with the major drivers being logging in the lowland forests and subsistence agriculture throughout the country with comparatively minor contributions from forest fires, plantation establishment, and mining. 相似文献
19.
Stephen Frankel 《Culture, medicine and psychiatry》1980,4(2):95-117
This paper is concerned with illnesses in men that the Huli people of Papua New Guinea ascribe to sexual intercourse at a time deemed dangerous. Against the background of the complex of beliefs surrounding sexuality and reproduction, cases of such illnesses are analysed to determine the critical variables in the selection of this diagnosis and in the choice of strategies of management. 相似文献
20.
Blood group, red cell enzyme and serum protein types in the Buka Islanders, Papua New Guinea 总被引:1,自引:0,他引:1
Genetic marker studies on a sample of 80 speakers of the Petats and Tinputs families of languages, all pupils at a single high school, indicate a homogeneity among them which can be extrapolated to their areas of origin. Buka and its offshore islands and the northern part of Bougainville Island in the North Solomons Province of Papua New Guinea. Several markers systems, most notably first-locus phosphoglucomutase and liver acetyltransferase, reinforce the morphological evidence that these peoples are quite distinct from most other Papua New Guinea populations, with whom, however, there has been some gene exchange, probably through East New Britain. Their principal affinities are with the peoples of the Solomon Islands to the south. 相似文献