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1.
Excavated and museum skeletons of the postcontact period revealed cribra orbitalia in four native ethnolinguistic divisions of the British Columbia coast, Haida, Kwakiutl, Nootka, and Coast Salish. Affected skulls were distributed among 25 of 35 localities, indicating widespread occurrence in a mainly heterogeneous population. Manifestations were similar to porotic hyperostosis, and additional lesions in the sample tend to support the concept that cribra orbitalia is related to anemia. Both inherited and acquired disorders may have been involved in the etiology. A uniquely high incidence of 52.9% occurred in immature of the Haida, a relatively homogeneous population. However, marked variability in expression by age group and by sex in the total sample is suggestive of iron-deficiency anemia. The data and historical information parallel modern expectations of susceptibility. Among 454 skulls, cribra orbitalia occurred in 32.7% of growing children and adolescents, 19% of infants and toddlers, 13.3% of adult females, and 4.8% of adult males. Postcontact disruptions and disease may have figured in promoting iron-deficiency anemia, but noted precontact occurrences may also have been due to the disorder.  相似文献   

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To gain a better understanding of North American population history, complete mitochondrial genomes (mitogenomes) were generated from four ancient and three living individuals of the northern Northwest Coast of North America, specifically the north coast of British Columbia, Canada, current home to the indigenous Tsimshian, Haida, and Nisga’a. The mitogenomes of all individuals were previously unknown and assigned to new sub-haplogroup designations D4h3a7, A2ag and A2ah. The analysis of mitogenomes allows for more detailed analyses of presumed ancestor–descendant relationships than sequencing only the HVSI region of the mitochondrial genome, a more traditional approach in local population studies. The results of this study provide contrasting examples of the evolution of Native American mitogenomes. Those belonging to sub-haplogroups A2ag and A2ah exhibit temporal continuity in this region for 5000 years up until the present day. Of possible associative significance is that archaeologically identified house structures in this region maintain similar characteristics for this same period of time, demonstrating cultural continuity in residence patterns. The individual dated to 6000 years before present (BP) exhibited a mitogenome belonging to sub-haplogroup D4h3a. This sub-haplogroup was earlier identified in the same general area at 10300 years BP on Prince of Wales Island, Alaska, and may have gone extinct, as it has not been observed in any living individuals of the Northwest Coast. The presented case studies demonstrate the different evolutionary paths of mitogenomes over time on the Northwest Coast.  相似文献   

5.
A total of 105 plants used for food and medicine and 11 animals hunted and gathered for meat by the Khasis and Garos of Meghalaya were identified. Of the total plants recorded, 85 were used by the Garos alone, only three by the Khasis whereas the other 17 were used by both tribes. In addition to fresh use in-season many plant products were processed for storage and use off-season. Although all adults were familiar with various uses of plants and animals, the village elders were more knowledgeable. Garos have especially knowledgeable curers. Wild foods are of particular value for tiding over lean periods when resources from agriculture and animal husbandry systems are scarce, especially for the poorer sections of society. The importance of recording the use of plants and animals in this region is especially important because of rapid loss of rain forest habitats.  相似文献   

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Over the past several decades, archeological research on the Northwest Coast of North America has focused on the evolution of the coast's well‐known native societies. This research has two broad goals: building local and regional culture histories spanning the Holocene and answering processual questions about the evolution and persistence of cultural complexity among hunter‐gatherers. Cultural complexity includes relatively dense populations, partial to full sedentism, corporate groups, some degree of occupational specialization, permanent social inequality, and control of property. 1 - 3 Recently archeologists have begun to investigate whether the coast was a possible route for the peopling of North America. Presently, the earliest known sites on the coast date to about 9,000 BC, although it is likely that the initial occupation was earlier. Some aspects of cultural complexity had developed on the coast by 2,500 BC, with permanent inequality present by 900 BC, if not earlier. Central to this development were large corporate households, intensive food production and storage, and technological innovations including water‐tight wooden containers and large‐capacity boats. Patterns of complexity on the coast continued to change through the arrival of Europeans in the mid‐1700s.  相似文献   

7.
The aboriginal culture of the Northwest Coast is well known for its elaboration of cultural forms and reliance on the prolific fisheries of the region. Less well understood is the role indigenous plants played in the subsistence of the native peoples. A search of the historical and ethnographic literature indicates that bracken (Pteridium aquilinum Kuhn) was a major item in the dietary of the peoples of western Washington contributing both starch and fiber. This fern was collected and prepared by native women as a form of “flour” and baked or dried into cakes or bread. The record also indicates plant management by burning which has not previously been considered as a systematic method of production for the foraging societies of western Washington.  相似文献   

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Food Preference and Reproductive Plasticity in an Invasive Freshwater Snail   总被引:10,自引:1,他引:9  
The freshwater apple snail Pomacea canaliculata has become a major crop pest in southeast Asia and Hawai'i and threatens natural wetland habitats in these regions and elsewhere. Deliberately introduced as a potential human food resource, it has also been proposed as a possible biocontrol agent against aquatic weeds. Various factors may facilitate its rapid invasion of new areas; we focus on two: growth rate and food preference. Our field observations and laboratory experiments suggest that in Hawai'i P. canaliculata reaches reproductive maturity in 10 months or more, less time than in its native temperate and seasonal Argentina, where it takes 2 years, but longer than in parts of southeast Asia, where it may take as little as 2 months. This increased growth rate, and thence reproductive rate, probably facilitate rapid population growth. Although P. canaliculata is usually considered an indiscriminate generalist macrophytophagous feeder, laboratory experiments indicated preferences among the dominant plants at our field site and growth rate differences when constrained to feed only on one of these plants. Water hyacinth (Eichhornia crassipes), a major invasive weed, was not preferred in food choice experiments, and snails offered only water hyacinth on which to feed did not differ in growth rate from unfed snails. Another important invasive weed, water lettuce (Pistia stratiotes), was also not preferred, but snails fed on it did grow, though not as quickly as those fed on green-leaf lettuce. Among the food plants offered in the experiments the native Vigna marina was the most preferred. Therefore, although a generalist, P. canaliculata exhibits some discrimination among food plants. We recommend that it not be introduced for use as a biological control agent for aquatic weeds.  相似文献   

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The Amur sleeper diet spectrum was investigated in addition to its spatial, seasonal and size-related changes, in order to predict which groups of native prey would be most affected by this exotic predator that has rapidly invaded many Eastern and Central European inland waters in recent decades. In total, 527 Perccottus glenii individuals were collected in four sites in the Włocławski Reservoir (the Vistula River, Baltic basin, Poland). Altogether 50 food categories were identified, including crustaceans, insects, molluscs, annelids, araneids, fishes and amphibians. Most of them were associated with aquatic vegetation, indicating that the Amur sleeper collects its prey from the submerged plants rather than directly from the bottom sediments. Amphipods and chironomid larvae, supplemented by zygopteran larvae and molluscs, composed the main forage base in all studied sites, although their importance was varied. The diet composition differed among P. glenii size-groups. Significant variation was found in numeric abundance of amphipods, chironomid larvae, fish and zygopteran larvae (Kruskal–Wallis P < 0.01). Seasonal changes in the diet were also observed whereby in spring and summer, dipteran larvae and amphipods were prevalent food items; the importance of molluscs and zygopteran larvae increased considerably in September; and fish showed the highest occurrence in June, July and August. The broad diet spectrum of the Amur sleeper indicates that it is a non-selective, opportunistic predator and that several taxonomic groups of native hydrofauna as well as macroinvetebrates and fish may be affected by its presence. The highly flexible feeding strategy undoubtedly favours Amur sleeper expansion in invaded watersheds.  相似文献   

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Ecological interactions often vary geographically. Work in salt marshes on the Atlantic Coast of the United States has documented community-wide latitudinal gradients in plant palatability and plant traits that may be driven in part by greater herbivore pressure at low latitudes. To determine if similar patterns exist elsewhere, we studied six taxa of saltmarsh plants ( Atriplex , Juncus , Limonium , Salicornia , Spartina and Suaeda ) at European sites at high (Germany and the Netherlands) and low (Portugal and Spain) latitudes. We conducted feeding assays using both native and non-native consumers, and documented patterns of herbivore damage in the field. As in the United States, high-latitude plants tended to be more palatable than low-latitude plants when offered to consumers in paired feeding assays in the laboratory, although assays with grasshopper consumers were less consistent than those with crab consumers, and plants in the field at low-latitude sites tended to experience greater levels of herbivore pressure than plants at high-latitude sites. Similarly, high-latitude leaf litter was more palatable than litter from low-latitude plants when offered to consumers in paired feeding assays in the laboratory. Latitudinal gradients in plant palatability and herbivore pressure may be a general phenomenon, and may contribute to latitudinal gradients in decomposition processes.  相似文献   

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In 1972 Arashiyama West troop of Japanese macaques was transplanted to southcentral United States and kept in semi-free ranging conditions. The new environment provided an opportunity to assess aspects of the species' adaptive potential. About 1,500 feeding observations were made monthly over 6.5 months. Unlimited provisioned food was available, but monkeys utilized native plants immediately and use increased until it included 50+ % of the diet by weight. Shrubs provided 75% of foods in first month and 32% thereafter. Sorghum comprised 25% in May–July. Soil, arthropods, fungi, bulbs, and roots each comprised less 5%. Between 21 and 37 foods were utilized monthly. Monthly food uses corresponded to availability. Many food plants required unique handling by monkeys. Four general adaptive responses to potential foods are described. Evolution has clearly shaped the Japanese macaque into a highly omnivorous and behaviorally flexible animal.  相似文献   

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Biotechnological production and applications of phytases   总被引:2,自引:0,他引:2  
Phytases decompose phytate, which is the primary storage form of phosphate in plants. More than 10 years ago, the first commercial phytase product became available on the market. It offered to help farmers reduce phosphorus excretion of monogastric animals by replacing inorganic phosphates by microbial phytase in the animal diet. Phytase application can reduce phosphorus excretion by up to 50%, a feat that would contribute significantly toward environmental protection. Furthermore, phytase supplementation leads to improved availability of minerals and trace elements. In addition to its major application in animal nutrition, phytase is also used for processing of human food. Research in this field focuses on better mineral absorption and technical improvement of food processing. All commercial phytase preparations contain microbial enzymes produced by fermentation. A wide variety of phytases were discovered and characterized in the last 10 years. Initial steps to produce phytase in transgenic plants were also undertaken. A crucial role for its commercial success relates to the formulation of the enzyme solution delivered from fermentation. For liquid enzyme products, a long shelf life is achieved by the addition of stabilizing agents. More comfortable for many customers is the use of dry enzyme preparations. Different formulation technologies are used to produce enzyme powders that retain enzyme activity, are stable in application, resistant against high temperatures, dust-free, and easy to handle.  相似文献   

14.
Humans are altering the global distributional ranges of plants, while their co‐evolved herbivores are frequently left behind. Native herbivores often colonise non‐native plants, potentially reducing invasion success or causing economic loss to introduced agricultural crops. We developed a predictive model to forecast novel interactions and verified it with a data set containing hundreds of observed novel plant–insect interactions. Using a food network of 900 native European butterfly and moth species and 1944 native plants, we built an herbivore host‐use model. By extrapolating host use from the native herbivore–plant food network, we accurately forecasted the observed novel use of 459 non‐native plant species by native herbivores. Patterns that governed herbivore host breadth on co‐evolved native plants were equally important in determining non‐native hosts. Our results make the forecasting of novel herbivore communities feasible in order to better understand the fate and impact of introduced plants.  相似文献   

15.
周静帆  欧杨  周丽  刘昕岑  包蓉 《广西植物》2019,39(3):346-358
传统村落的植物景观反应了一个民族在长期实践中积累的植物认知和应用经验,该研究对云南省德宏州大盈江、瑞丽江流域的19个傣族传统村落进行了植物景观及应用调查。结果表明:德宏傣族传统村落植物景观水平分布为寨外(山林绿块+农田绿块+护堤绿带)——寨边(防护绿环+高山榕绿块)——寨内(绿点+绿线)的格局;垂直分布有5个景观层次;村寨内常见植物共181种,73科;村寨内植物多为人工栽培,具较强实用性,主要应用功能集中在食用、药用、观赏、防护隔离、香薰调味等方面;傣寨植物人文景观具宗教色彩。建议加强植物水平分布的空间联系,建立稳定的绿地系统格局;保持植物垂直景观层次,推广植物的建造功能应用;充分利用植物资源,形成产业优势;传承优秀的植物文化景观。推广植物在村落建设中的传统应用经验,促进民族村落与植物的可持续保护与发展,为德宏傣族人居环境建设与民族植物学应用提供科学依据。  相似文献   

16.
The indigenous people of Australia have a long and well documented history of using native plants as an essential component of their customary economy. However, few have engaged successfully in commerce based on native plant use. Recently there has been an increasing interest in exploring options for use of native plants for food, food additives, botanical medicines, and related purposes. In this paper, we determine the issues important to Aboriginal people in enterprise development utilizing plant products, and we define some of the factors affecting progress in realizing opportunities. The Aboriginal people with whom we have worked appear to prefer small-scale enterprises where they have community ownership of ideas and control of the rate and direction of development. Government could play a larger and more active role through supporting additional research and marketing information, providing training, and better matching policy and legislation to support indigenous development and reduce dependence of welfare.  相似文献   

17.
We examined the raccoon dog’s Nyctereutes procyonoides (Gray, 1834) diet in two agricultural landscapes of Germany and compared these results with other diet studies from its native and introduced ranges. The diet composition was influenced as well by the landscape structures as by the seasons: in the waterrich study area 2 amphibians (54.1%) and fish (10.8%) occurred more frequently in the samples. In study area 1 amphibians (19.0%) and invertebrates (69.4%) gained more significance in the diet in summer, whereas in winter samples maize (32.8%) was an important food item. The diet composition shifted according to the availability of different food items. Raccoon dogs, ability to feed temporarily on one food source may possibly cause a serious problem to endangered small populations of birds and amphibians. The review of 81 data sets from nine countries showed that seasons and locality affected the occurrence of most food items. However, comparable to the present study, small mammals, insects and plants were identified as important food items both in native and introduced ranges of the raccoon dog. In regard to its diet composition, gathering foraging strategy and inactivity during winter, the raccoon dog probably preys less often on game animals and birds than the native red fox Vulpes vulpes.  相似文献   

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We studied the feeding ecology of the critically endangered Red‐headed Wood Pigeon Columba janthina nitens, a subspecies endemic to a very remote and highly disturbed oceanic island chain, the Ogasawara Islands. An analysis based on high‐throughput sequencing (HTS) was undertaken on 627 faecal samples collected over 2 years from two island habitats, and food availability and the nutrient composition of the major fruits were also estimated. The HTS diet analysis detected 122 food plant taxa and showed clear seasonal and inter‐island variation in the diet of the Pigeons. The results indicated a preference for lipid‐rich fruits, but the diet changed according to the availability of food resources, perhaps reflecting the foraging strategy of the Pigeons in isolated island habitats with poor food resources. Pigeons also frequently consumed introduced plants at certain times of year, perhaps compensating for the lack of preferred native food resources. However, the degree of dependence on introduced plants appeared to differ between the two island habitats, so the different impacts of introduced plant eradication on the foraging conditions for the Pigeons on each island should be considered. HTS diet analysis combined with field data may be useful for monitoring the foraging conditions of endangered species and may also inform an appropriate conservation strategy in oceanic island ecosystems with complicated food webs that include both native and introduced species.  相似文献   

19.
The potential feeding advantages that are offered to the barred mudskipper Periophthalmus argentilineatus by its amphibious life-style were investigated. To this end the feeding ecology of these fish, the position they occupy in the mangrove food web and the importance of different morphological factors for their diet were studied. Analysis of gut contents showed that the major component of the barred mudskipper diet changes during growth from small crustaceans ( e.g. copepods and amphipods) to polychaetes to mangrove crabs. This dietary shift was found to be facilitated through enlargement of the mouth, as well as elongation of the gut. The use of stable isotope analysis revealed that barred mudskippers had a similar trophic position as other zoobenthivore fish species, but that their diet did not appear to be affected by competition for food with other zoobenthivores. The amphibious habits of the barred mudskipper provide specific advantages to its feeding ecology, such as access to an abundant food source of mangrove crabs, which are mostly inaccessible for other fish species.  相似文献   

20.
Restoration approaches rely on native plants; yet in some situations, natural vegetation may not grow fast enough to prevent the fragmentation of original vegetation and the consequent negative impacts on fauna. In this context, some introduced plants may grow faster and provide more food than native species, and they may also contribute to human livelihood. We investigate to what extent introduced plant species (1) can serve as habitat and food for endemic vertebrates and (2) provide benefits to local people. We address this question in Madagascar, characterized by high degrees of endemism, long histories of coevolution between endemic species, highly fragmented forests, and a high reliance of the rural population on natural resources. A literature search for interactions between endemic fauna and introduced flora revealed that 100 of 1,379 introduced species recorded for Madagascar are used by endemic vertebrates. They provide food mainly for primates, flying foxes, and birds, and habitat for all terrestrial vertebrate groups. One hundred vertebrate species were reported to use introduced plants, many of which are fast growing and are useful for populations. Although these introduced plants should be approached with caution due to their potentially invasive behavior, many introduced plants can provide services for the native fauna and for humans. For example, trees can provide an interim solution to secure the survival of endemic fauna that otherwise would be lost due to fragmentation effects. These plants could bridge the time lag until native forest regeneration or restoration with native trees will have become effective.  相似文献   

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