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1.
Secondary Forests on Anthropogenic Soils of the Middle Madeira River: Valuation, Local Knowledge, and Landscape Domestication in Brazilian Amazonia. Anthropogenic forests and soils are widespread throughout Amazonia and are the product of the landscape domestication process carried out by Amazonian societies since pre-Colombian times. Areas of Terra Preta de índio (TPI, Amazonian Dark Earths) are recognized by local rural residents and associated with specific forms of use and management of these soils and associated secondary forests. We used a quantitative approach to investigate how secondary forests on TPI are recognized and used by local residents along the middle Madeira River, Central Amazonia. Sixty-two residents were interviewed in three riverside communities and listed the ethnospecies and their uses in secondary forests on TPI and on non-anthropogenic soils (NAS). Local residents mentioned more ethnospecies on TPI (mean ± standard deviation: 19.5 ± 8.9) than on NAS (17.4 ± 8.5), and the use value of the environment to the informants (UVia) was higher on TPI (19 ± 5.7) than on NAS (16.2 ± 6.0). Eleven ethnospecies were classified as anthropogenic soil indicators, among which three intensively used palms are widely recognized as indicators of anthropogenic areas and two are domesticated to some degree. The intimate and lasting interactions between humans and TPI have favored the maintenance of secondary forests in these domesticated landscapes with a diverse assemblage of useful and domesticated species. Rural residents in Amazonia recognize these forests as an important source of food and other resources. The use, management, and traditional knowledge related to these domesticated landscapes may provide useful information for the understanding of Amazonian historical ecology and for the design of more efficient biodiversity management and conservation plans.  相似文献   

2.
Morphometric Analysis of Sunflower ( Helianthus annuus L.) Achenes from Mexico and Eastern North America. Sunflower (Helianthus annuus L.) has played a major role in the evolution of agricultural systems in the Americas. The discovery of ancient domesticated remains from archaeological deposits in pre-Columbian Mexico offers new dimensions to widely accepted viewpoints on the domestication pattern of H. annuus. Although American sunflower populations north of Mexico have been examined extensively, Mexican indigenous domesticated landraces have not been studied in any detail. In this study, we morphologically assessed wild and domesticated sunflower achenes from Mexico and compared them to similar datasets from eastern North America. Additionally, we evaluated the utility of four computer-assisted shape measurements in discriminating between wild and domesticated sunflower achenes (fruits) and compared variation in achene size among modern wild and cultivated populations from both Mexico and the U.S. We found that, of the shape parameters tested, none were informative in distinguishing wild achenes from domesticated varieties. Subsequent size analysis, using conventional parameters of length, width, and thickness, showed that modern wild populations from Mexico had smaller achenes compared to modern populations from eastern North America. Domesticated achenes unearthed from Mexican archaeological sites, however, were significantly larger than the early domesticated specimens recovered from eastern North America. Our methodological results indicate that variation in archaeological sunflower achenes is better described by conventional size parameters rather than computerized shape analysis.  相似文献   

3.
BackgroundThe genetic provenance of domesticated plants and the routes along which they were disseminated in prehistory have been a long-standing source of debate. Much of this debate has focused on identifying centers of origins for individual crops. However, many important crops show clear genetic signatures of multiple domestications, inconsistent with geographically circumscribed centers of origin. To better understand the genetic contributions of wild populations to domesticated barley, we compare single nucleotide polymorphism frequencies from 803 barley landraces to 277 accessions from wild populations.ResultsWe find that the genetic contribution of individual wild populations differs across the genome. Despite extensive human movement and admixture of barley landraces since domestication, individual landrace genomes indicate a pattern of shared ancestry with geographically proximate wild barley populations. This results in landraces with a mosaic of ancestry from multiple source populations rather than discrete centers of origin. We rule out recent introgression, suggesting that these contributions are ancient. The over-representation in landraces of genomic segments from local wild populations suggests that wild populations contributed locally adaptive variation to primitive varieties.ConclusionsThis study increases our understanding of the evolutionary process associated with the transition from wild to domesticated barley. Our findings indicate that cultivated barley is comprised of multiple source populations with unequal contributions traceable across the genome. We detect putative adaptive variants and identify the wild progenitor conferring those variants.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-015-0712-3) contains supplementary material, which is available to authorized users.  相似文献   

4.
Documented Utility and Biocultural Value of Aloe L. (Asphodelaceae): A Review. The genus Aloe L. (Asphodelaceae) comprises 548 accepted species, of which at least one-third are documented as having some utilitarian value. The group is of conservation concern due to habitat loss and being extensively collected from the wild for horticulture and natural products. Cultural value is increasingly important in the effective conservation of biodiversity. The present study evaluated the biocultural value of the known uses of Aloe, excluding the domesticated and commercially cultivated A. vera. Over 1,400 use records representing 173 species were collated from the literature and through personal observation; this paper presents a synopsis of uses in each of 11 use categories. Medicinal uses of Aloe were described by 74% of the use records, followed by social and environmental uses (both 5%). Species yielding natural products, notably A. ferox and A. perryi, were most frequently cited in the literature. Consensus ratios indicate that the most valued uses of Aloe are in medicine and pest control against arthropods and other invertebrates.  相似文献   

5.
6.
7.
 This paper deals with the use of cladistic methods and cladograms in phylogeny reconstruction in plant groups containing numerous taxa. How accurate are the cladograms as to details? Accuracy tests at the level of details require an independently known phylogeny, which excludes most plant groups, but such tests can be carried out in domesticated and experimental plant groups which have documented pedigrees. Four such tests are known and are presented here: a new case in Gilia and three previously published cases in Avena, Hordeum, and Helianthus. The four cases include domesticated and experimental plants, use of morphological and molecular evidence, and presence of dichotomous as well as reticulate phylogenies. The cladograms of the four plant groups all differ in significant details from the known pedigrees. These results are discussed in relation to problems of interpretation of cladograms. Received March 21, 2000 Accepted August 16, 2001  相似文献   

8.
《Anthrozo?s》2013,26(2):98-118
Abstract

The most widely accepted hypothesis of the origin of the dog, Canis familiaris, is that the dog is a domesticated gray wolf, Canis lupus. This paper reviews the evidence for this conclusion, finds many unanswered questions and conceptual gaps in the wolf origin hypothesis, and explores the alternative hypothesis that the most likely ancestor of the domestic dog was a medium-size, generalist canid.  相似文献   

9.
《Plains anthropologist》2013,58(63):55-72
Abstract

This report contains an analysis of the carbonized seed remains from the Mitchell Site (39DV2), an Over Focus village near Mitchell, South Dakota. The motive for the study is to explore the amount and kinds of nutritional and material resources which the botanical world (of seeds) provided these villagers. Eight propositions and goals are outlined to be tested by the analysis. The use of flotation and sieving through #40 (.0165 in.) mesh screen of all materials was found to be the most efficient method for recovering seed remains. Forty-five genera and species of prehistorically-deposited (carbonized) seeds are identified. Corn appears in nearly all samples, suggesting that this crop, along with bison meat, provided a major source of food. Quantities of the weed seeds Chenopodium sp. and Amaranthus sp. are clearly associated with corn and seeds of the domesticated sunflower. Tobacco seeds are also identified for the second time on the Plains. A table of associations and specific Chi-square tests are used to interpret the relative significance of the seeds identified here. In addition, ethnographic data on the use of particular seed types is included where no archaeological use can be inferred.  相似文献   

10.
Illegal Palm Heart (Geonoma edulis) Harvest in Costa Rican National Parks: Patterns of Consumption and Extraction. Illegal extraction of non-timber forest products in the tropics is widespread, and many protected areas face the challenge of balancing conservation needs with cultural practices related to the use and extraction of animals and plants. We studied the illegal wild palm heart extraction of Geonoma edulis, locally known as súrtuba, in Volcán Poás and Braulio Carrillo National Parks in Costa Rica. Through 96 questionnaires administered in three communities bordering these national parks, and by semistructured interviews with poachers and park managers, this study examined extraction and consumption motives, patterns, and frequencies. This palm is sought out by the communities for use during Holy Week to satisfy cultural traditions, for its associated nutritive value, and because of its unique bitter flavor, not comparable to domesticated palm heart. Whereas the majority of the respondents consume it during Holy Week (55.2%), a substantial number (27.1%) consume G. edulis palm heart at least once a month. The majority extract once a year (58%); however, a minority (2.1%) rely on G. edulis for economic subsistence. This accounts for 72.6% of the reported extraction (over 4,500 palms per year) and is supplying a year-round market for nontraditional use. Our results show that what most likely began as a cultural tradition has become an uncontrolled, nontraditional source of income. Additional efforts should determine the feasibility of limited extraction outside protected areas to satisfy traditional use. Such an effort entails the decentralization of biodiversity policies and innovative methods to implement protective measures, as well as incentives for community involvement in the management of this palm heart species.  相似文献   

11.
ABSTRACT

Capsule: Non-breeding waterbirds are more likely to respond to drone approach when in larger flocks, and responses are more likely in arable and coastal habitats than at inland lochs.

Aims: To investigate the extent to which drones are a potential source of disturbance to non-breeding waterbirds.

Methods: Using a commercially available quadcopter drone, we approached waterbird flocks of varying sizes in coastal, freshwater, and arable habitats following a standardized protocol.

Results: Waterbirds at coastal sites and in arable fields were more likely to respond to drone approach than those at inland freshwater bodies. Larger flocks were more likely to respond to drone approach and responded at a greater distance than smaller flocks.

Conclusion: Repeated drone use at coastal and arable sites with large aggregations of feeding or roosting waterbirds could cause energetically costly flight responses, increased stress, and effective loss of available habitat. At such sites, it may be beneficial to regulate recreational and commercial drone use to minimize potential disturbance effects.  相似文献   

12.
Idan Breier 《Anthrozo?s》2013,26(6):657-672
ABSTRACT

This paper examines the relations between humans and wild animals in the lands of the Bible and ancient Near East and the way in which these cultures used various creatures and their characteristics as metaphors for dangerous enemies. It focuses on three particular periods in which the sources at our disposal document human–wild animal interactions. The first section discusses the emergence of civilization in Mesopotamia as reflected in various texts, discussing their portrait of the epoch in which human culture took shape and domesticated animals began to be clearly differentiated from wild ones. The second part looks at human–canine relations—wild dogs and their domesticated counterparts—briefly surveying how the former serve as metaphors for enemies beyond inhabited regions as evinced in the Egyptian El-Amarna archive. The third section analyzes the human–animal relations portrayed in the biblical texts, reviewing the theological principles they adopt in relation to the animal kingdom and the way in which wild animals became a metaphor for both wicked adversaries and striking physical attributes.  相似文献   

13.
Taro (Colocasia esculenta [L.] Schott) Cultivation in Vertical Wet-Dry Environments: Farmers’ Techniques and Cultivar Diversity in Southwestern Ethiopia. Taro (Colocasia esculenta [L.] Schott) is a food crop that was domesticated in Asia and the Pacific region and is now grown in the humid tropics. Following its arrival in Africa in ancient times, it may have adapted to the drier environments. In this ethnographic study, I present a particular case of taro cultivation and uses by a group of farmers in the mountains of southwestern Ethiopia. There are 36 named cultivars of taro for which diversity is maintained through different cultivation techniques and culinary practices in wet and dry environments that vary in elevation. Because taro in dry lowland environments has recently been replaced by the introduction of new crops, it is possible that the drought-tolerant eddoe-type cultivars, which are traditionally dominant in Africa, are now in danger of disappearing.  相似文献   

14.
Abstract

This paper considers the surface structural properties and crystal morphology of crystalline s-triazine. A key feature of the computational approach adopted is the consideration of surface structural relaxation of the uppermost section of the crystal and the use of non-rigid molecules. Crystal morphologies calculated on the basis of surface energies and attachment energies are considered.  相似文献   

15.
In recent decades, human–Rangifer (reindeer and caribou) interactions have increasingly been studied from a scientific perspective. Many of the studies have examined Norwegian wild reindeer or caribou in North America. It is often questioned whether results from these studies can be applied to reindeer in managed herds, as these animals have been exposed to domestication and are also more used to humans. In order to examine the domesticated reindeer’s reactions to various disturbance sources, we reviewed 18 studies of the effects of human activity and infrastructure on 12 populations of domesticated reindeer and compared these to studies on wild reindeer and caribou; based on this, we discuss the effects of domestication and tameness on reindeer responses to anthropogenic disturbance. We also consider the relevance of spatial and temporal scales and data collection methods when evaluating the results of these studies. The reviewed studies showed that domesticated reindeer exhibit avoidance behaviours up to 12 km away from infrastructure and sites of human activity and that the area they avoid may shift between seasons and years. Despite a long domestication process, reindeer within Sami reindeer-herding systems exhibit similar patterns of large-scale avoidance of anthropogenic disturbance as wild Rangifer, although the strength of their response may sometimes differ. This is not surprising since current Sami reindeer husbandry represents an extensive form of pastoralism, and the reindeer are not particularly tame. To obtain a true picture of how reindeer use their ranges, it is of fundamental importance to study the response pattern at a spatial and temporal scale that is relevant to the reindeer, whether domesticated or wild.  相似文献   

16.
Background and AimsDomesticated maize (Zea mays ssp. mays) generally forms between two and six seminal roots, while its wild ancestor, Mexican annual teosinte (Zea mays ssp. parviglumis), typically lacks seminal roots. Maize also produces larger seeds than teosinte, and it generally has higher growth rates as a seedling. Maize was originally domesticated in the tropical soils of southern Mexico, but it was later brought to the Mexican highlands before spreading to other parts of the continent, where it experienced different soil resource constraints. The aims of this study were to understand the impacts of increased seminal root number on seedling nitrogen and phosphorus acquisition and to model how differences in maize and teosinte phenotypes might have contributed to increased seminal root number in domesticated maize.MethodsSeedling root system architectural models of a teosinte accession and a maize landrace were constructed by parameterizing the functional–structural plant model OpenSimRoot using plants grown in mesocosms. Seedling growth was simulated in a low-phosphorus environment, multiple low-nitrogen environments, and at variable planting densities. Models were also constructed to combine individual components of the maize and teosinte phenotypes.Key ResultsSeminal roots contributed ~35 % of the nitrogen and phosphorus acquired by maize landrace seedlings in the first 25 d after planting. Increased seminal root number improved plant nitrogen acquisition under low-nitrogen environments with varying precipitation patterns, fertilization rates, soil textures and planting densities. Models suggested that the optimal number of seminal roots for nutrient acquisition in teosinte is constrained by its limited seed carbohydrate reserves.ConclusionsSeminal roots can improve the acquisition of both nitrogen and phosphorus in maize seedlings, and the increase in seed size associated with maize domestication may have facilitated increased seminal root number.  相似文献   

17.
Purpose

Despite the wide use of LCA for environmental profiling, the approach for determining the system boundary within LCA models continues to be subjective and lacking in mathematical rigor. As a result, life cycle models are often developed in an ad hoc manner, and are difficult to compare. Significant environmental impacts may be inadvertently left out. Overcoming this shortcoming can help elicit greater confidence in life cycle models and their use for decision making.

Methods

This paper describes a framework for hybrid life cycle model generation by selecting activities based on their importance, parametric uncertainty, and contribution to network complexity. The importance of activities is determined by structural path analysis—which then guides the construction of life cycle models based on uncertainty and complexity indicators. Information about uncertainty is from the available life cycle inventory; complexity is quantified by cost or granularity. The life cycle model is developed in a hierarchical manner by adding the most important activities until error requirements are satisfied or network complexity exceeds user-specified constraints.

Results and Discussion

The framework is applied to an illustrative example for building a hybrid LCA model. Since this is a constructed example, the results can be compared with the actual impact, to validate the approach. This application demonstrates how the algorithm sequentially develops a life cycle model of acceptable uncertainty and network complexity. Challenges in applying this framework to practical problems are discussed.

Conclusion

The presented algorithm designs system boundaries between scales of hybrid LCA models, includes or omits activities from the system based on path analysis of environmental impact contribution at upstream network nodes, and provides model quality indicators that permit comparison between different LCA models.

  相似文献   

18.
Domesticated Asian rice (Oryza sativa) is one of the oldest domesticated crop species in the world, having fed more people than any other plant in human history. We report the patterns of DNA sequence variation in rice and its wild ancestor, O. rufipogon, across 111 randomly chosen gene fragments, and use these to infer the evolutionary dynamics that led to the origins of rice. There is a genome-wide excess of high-frequency derived single nucleotide polymorphisms (SNPs) in O. sativa varieties, a pattern that has not been reported for other crop species. We developed several alternative models to explain contemporary patterns of polymorphisms in rice, including a (i) selectively neutral population bottleneck model, (ii) bottleneck plus migration model, (iii) multiple selective sweeps model, and (iv) bottleneck plus selective sweeps model. We find that a simple bottleneck model, which has been the dominant demographic model for domesticated species, cannot explain the derived nucleotide polymorphism site frequency spectrum in rice. Instead, a bottleneck model that incorporates selective sweeps, or a more complex demographic model that includes subdivision and gene flow, are more plausible explanations for patterns of variation in domesticated rice varieties. If selective sweeps are indeed the explanation for the observed nucleotide data of domesticated rice, it suggests that strong selection can leave its imprint on genome-wide polymorphism patterns, contrary to expectations that selection results only in a local signature of variation.  相似文献   

19.
Progressive and regressive changes of brain size within Equidae From Hyracotherium to Equus brain size increased eightfold independently from body size. In domestication brain size is reduced; within mammals the amount of reduction depends on cephalization. Species with high cephalization show much more reductions than those with low cephalization. Among the ancestors of domesticated mammals wild horses have the highest cephalization level; reduction of brain size of more than 30% in domesticated horses could be expected. The size of the brain case of domesticated horses is only 14 % smaller than in wild Przewalski horses. We think that populations of the wild Przewalski horses have been crossbreeds between wild and domesticated animals. There is no difference in size of the brain case capacity and the brain weight between the Przewalski horses from zoological gardens and domesticated horses. This may be due to further crossbreeding between Zoo-Przewalski horses and domesticated horses and to artificial selection.  相似文献   

20.
《Plains anthropologist》2013,58(83):35-38
Abstract

The assumption of complexity seems to dominate much of anthropological thinking. This is clearly indicated by the frequency of use of complex multivariate statistics such as factor analysis. It is argued here that human behavior may often be much simpler than assumed and that the optimal approach to data analysis is to assume simplicity until demonstrated otherwise. It is also argued that when multivariate statistics are used, they are most effectively used in a deductive framework.  相似文献   

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