Recent History and Geography of Virtual Water Trade

The global trade of goods is associated with a virtual transfer of the water required for their production. The way changes in trade affect the virtual redistribution of freshwater resources has been recently documented through the analysis of the virtual water network. It is, however, unclear how these changes are contributed by different types of products and regions of the world. Here we show how the global patterns of virtual water transport are contributed by the trade of different commodity types, including plant, animal, luxury (e.g., coffee, tea, and alcohol), and other products. Major contributors to the virtual water network exhibit different trade patterns with regard to these commodity types. The net importers rely on the supply of virtual water from a small percentage of the global population. However, discrepancies exist among the different commodity networks. While the total virtual water flux through the network has increased between 1986 and 2010, the proportions associated with the four commodity groups have remained relatively stable. However, some of the major players have shown significant changes in the virtual water imports and exports associated with those commodity groups. For instance, China has switched from being a net exporter of virtual water associated with other products (non-edible plant and animal products typically used for manufacturing) to being the largest importer, accounting for 31% of the total water virtually transported with these products. Conversely, in the case of The United states of America, the commodity proportions have remained overall unchanged throughout the study period: the virtual water exports from The United States of America are dominated by plant products, whereas the imports are comprised mainly of animal and luxury products.     

Signaling by consumption in a native Amazonian society

People signal status by producing, distributing, or consuming goods. Behavioral ecologists working with foragers stress signaling by production (e.g., supply of wildlife), whereas economists working in industrial economies stress signaling by individual consumption or expenditures. As foraging economies experience economic transformations, one expects greater reliance on individual consumption compared with production to signal status. We test two hypotheses: if people signal by individual consumption, they will allocate a higher share of their monetary expenditures to luxuries or to visible durable goods (Hypothesis 1) and the propensity to signal by individual consumption will be more salient among people closer to market towns (Hypothesis 2). To test the hypotheses, we draw on data from a native Amazonian society of foragers and slash-and-burn farmers in Bolivia (Tsimane') undergoing increasing exposure to the market economy. The sample included 161 women and 257 men 16+ years of age in 13 villages. The dependent variable was the share of total monetary expenditures allocated to different types of durable goods (e.g., clothing, luxuries, highly visible and less visible goods) during the previous year. Separate OLS regressions were used for women and men. We found support for Hypothesis 1. Higher levels of total monetary expenditures bore a positive association with the share of expenditures allocated to luxury goods and a negative association with expenditures allocated to less visible durable goods. Only among women did we find a positive association between total expenditures and the share of expenditures allocated to highly visible goods. We found no support for Hypothesis 2.     

On market forces and human evolution

This paper studies how an institution such as markets affects the evolution of mankind. My key point is that the forces of natural selection are made weaker because trade allows people to specialize in those activities where they are strong, and to offset their weaknesses by purchasing adequate goods on the market. Absent trade, people must allocate their time among all the activities necessary for their fitness. A productivity advantage in any given dimension will increase survival probability, so that in the long run natural selection makes sure that population is entirely made of individuals with the strongest alleles at all loci. Under trade, there exist long-run equilibria where weaker individuals are able to achieve the same survival potential as the fittest, by specializing in activities where they are not at a disadvantage, and purchasing goods that are substitute for activities for which they are weak.     

A BIOLOGICAL MARKET ANALYSIS OF THE PLANT‐MYCORRHIZAL SYMBIOSIS

It has been argued that cooperative behavior in the plant‐mycorrhizal mutualism resembles trade in a market economy and can be understood using economic tools. Here, we assess the validity of this “biological market” analogy by investigating whether a market mechanism—that is, competition between partners over the price at which they provide goods—could be the outcome of natural selection. Then, we consider the conditions under which this market mechanism is sufficient to maintain mutualistic trade. We find that: (i) as in a market, individuals are favored to divide resources among trading partners in direct relation to the relative amount of resources received, termed linear proportional discrimination; (ii) mutualistic trade is more likely to be favored when individuals are able to interact with more partners of both species, and when there is a greater relative difference between the species in their ability to directly acquire different resources; (iii) if trade is favored, then either one or both species is favored to give up acquiring one resource directly, and vice versa. We then formulate testable predictions as to how environmental changes and coevolved responses of plants and mycorrhizal fungi will influence plant fitness (crop yields) in agricultural ecosystems.     

Conservation Implications of Rapid Shifts in the Trade of Wild African and Asian Pythons

Pythons are harvested for the international leather industry and pet trade. We analyzed the CITES export records (1999–2008) of the most intensively commercialized wild pythons (Python regius, Python sebae, Python reticulatus, Python molurus, Python curtus species complex) from African and Asian countries where reliable data on trade rates and ecology are available. Mean declared annual numbers of exported pythons were 30,000 in five African countries and 164,000 in Indonesia. Trade intensity tripled in Indonesia over the last decade, but declined in Africa. African international trade is exclusively associated with the pet market (mainly United States and Europe), whereas Asian pythons are sold mostly for luxury leather, albeit more recently also for the pet trade. A negative correlation between the annual numbers of pythons traded in Africa vs. Asia suggests a rapid and recent shift of the pressure exerted on wild populations in the two main exporting continents. We also found a strong effect of the currency exchange rate (i.e., U.S.$/€, the currencies used by the major importing countries) on African python exports: when the cost per African python increased, importers relied increasingly on Asian providers for pet trade. Overall, our data indicate that Asian pythons (especially P. reticulatus) might be threatened due to the rapidly increasing pressure, whereas the decreasing international trade in African pythons is likely more sustainable.     

Demand and Dematerialization Impacts of Second-Hand Markets

The potential for second-hand markets to reduce demand for new goods is investigated. Using a variant of an economic model originally developed by Anderson and Ginsburgh, the physical implications for material use are explored. The second-hand market grows if transaction costs decrease or if product lifetime increases. In this model, growth of the secondhand market reduces demand for new goods if there are waste used goods that can be brought into the market. But if there is not a ready supply of waste used goods, growth of the second-hand market can increase demand for new goods, thereby increasing material consumption. Moreover, even when second-hand sales reduce demand for new goods, it is typically not on a one-for-one basis. The extent to which the purchase of used goods replaces the purchase of new goods is shown to be an explicit function of the relative value provided by used versus new goods.     

Settlement Hierarchies and Political Complexity in Nonmarket Societies: The Formative Period of the Valley of Mexico

Archaeologists have long recognized that increases in political centralization often coincide with the growth of regional settlement hierarchies. Here I develop a theoretical model which explicitly relates certain aspects of political complexity to variation in settlement size. This model applies specifically to hierarchical societies without well-developed market economies—societies which Service would classify as chiefdoms and (perhaps) simple states. Using settlement data from the Formative Period Valley of Mexico, I show how this model is useful in measuring (1) the number of levels in a regional hierarchy, (2) the degree of political centralization, and (3) the relative amount of surplus food mobilized to support the political establishment.     

Social benefits of luxury brands as costly signals of wealth and status

Drawing from costly signaling theory, we predicted that luxury consumption enhances status and produces benefits in social interactions. Across seven experiments, displays of luxury — manipulated through brand labels on clothes — elicited different kinds of preferential treatment, which even resulted in financial benefits to people who engaged in conspicuous consumption. Furthermore, we tested preconditions in which the beneficial consequences of conspicuous consumption may arise and determined the proximate mechanisms underlying them. The present data suggest that luxury consumption can be a profitable social strategy because conspicuous displays of luxury qualify as a costly signaling trait that elicits status-dependent favorable treatment in human social interactions.     

Impacts of Pathogen Introduction Risk on Importer Behavior and Gains from Trade in the Livestock Industry

Trade eliminates geographic barriers, allowing for novel exchange of goods and services, but also creates pathways for the unintentional spread of infectious pathogens such as foot and mouth disease. In the absence of trade regulation, a producer’s choice of import origin depends on relative prices and costs associated with trading partners. This paper develops a framework for exploring importer behavior in a non-regulated economy, allowing for price and risk heterogeneity among potential import sources. In the model, importers determine the risk of introducing foot and mouth disease to home soil and choose import volumes using risk and market data. When importers consider the possibility of unreported or undetected outbreaks, they choose to import from multiple sources to minimize risk and simultaneously create gains from trade over the regulated outcome. Our results have implications for the development of import and inspection policies that could be specifically designed to target highest risk imports of livestock.     

广州市花地湾市场宠物两栖动物调查

通过对广州市花地湾花鸟鱼虫市场两栖类宠物贸易进行为期3年27次调查,共记录贸易两栖类类44种,隶属2目16科35属。有尾目(Caudata)2科7属8种,钝口螈科(Ambystomatidae)1属2种,蝾螈科(Salamandridae)6属6种;无尾目(Anura)14科28属36种,铃蟾科(Bombinatoridae)1属1种,蟾蜍科(Bufonidae)3属3种,角花蟾科(Ceratophryidae)2属5种,其中1种为杂交种,丛蛙科(Dendrobatidae)2属4种,雨蛙科(Hylidae)3属5种,非洲树蛙科(Hyperoliidae)1属1种,角蟾科(Megophryidae)2属2种,姬蛙科(Microhylidae)5属6种,澳雨蛙科(Pelodryadidae)1属1种,叶泡蛙科(Phyllomedusidae)1属1种,负子蟾科(Pipidae)1属1种,箱头蛙科(Pyxicephalidae)1属1种,蛙科(Ranidae)2属2种,树蛙科(Rhacophoridae)3属3种。分布于国内的两栖类16种,外来物种共28种。受保护种类26种,所占比例达59.09%。讨论了两栖类宠物贸易对国内外珍稀濒危种类保护的压力、对生态系统的压力和对两爬类研究的影响。     

The Human Ecology of World Systems in East Africa: The Impact of the Ivory Trade

The impact on human ecology of the ivory trade entailed direct and indirect effects. First, the reduction or extermination of elephant populations had direct effects on the vegetation patterns over large areas. Second, the economic activities connected with hunting, transport, and trading affected regional systems of exchange and thereby, indirectly through the political economy, settlements, patterns of resource utilization, population parameters, and specialization of production. Ethnohistorical information from the 1800s suggests how coastal goods interacted with regional systems of exchange and environmental exploitation. Although such information cannot be directly projected onto the more distant past, it can be used to establish some possible pathways through which the hunting of elephants and transportation and trade of ivory could have affected the ecology of human resource use.     

Understanding agricultural virtual water flows in the world from an economic perspective: A long term study

The globalization process of the last half century entailed a growing trade in agricultural and food products. As a result, water has been transferred among countries, embodied in these goods. This paper studies the evolution of virtual water flows over the long term, analyzing the main driving factors through Decomposition Analysis. It contributes to the existing literature by offering a dynamic and economic interpretation of the historical changes in virtual water trade flows. In particular, this study points to a gradual increase in virtual water exchange, related to the upsurge of agricultural and food products trade in the world from 1965 to 2010. Although the origins and destinations of virtual water have changed, North America stands out as the primary net exporter of virtual water. Europe and Asia, on the other hand, with a high dependency on foreign water resources, appear as net importers of virtual water. Despite improvements in agricultural yields and the reallocation of production, the virtual water trade continues to increase globally via these significant commercial exchanges.     

A Novel Mini-DNA Barcoding Assay to Identify Processed Fins from Internationally Protected Shark Species

There is a growing need to identify shark products in trade, in part due to the recent listing of five commercially important species on the Appendices of the Convention on International Trade in Endangered Species (CITES; porbeagle, Lamna nasus, oceanic whitetip, Carcharhinus longimanus scalloped hammerhead, Sphyrna lewini, smooth hammerhead, S. zygaena and great hammerhead S. mokarran) in addition to three species listed in the early part of this century (whale, Rhincodon typus, basking, Cetorhinus maximus, and white, Carcharodon carcharias). Shark fins are traded internationally to supply the Asian dried seafood market, in which they are used to make the luxury dish shark fin soup. Shark fins usually enter international trade with their skin still intact and can be identified using morphological characters or standard DNA-barcoding approaches. Once they reach Asia and are traded in this region the skin is removed and they are treated with chemicals that eliminate many key diagnostic characters and degrade their DNA (“processed fins”). Here, we present a validated mini-barcode assay based on partial sequences of the cytochrome oxidase I gene that can reliably identify the processed fins of seven of the eight CITES listed shark species. We also demonstrate that the assay can even frequently identify the species or genus of origin of shark fin soup (31 out of 50 samples).     

The Eureka and Comstock Mounds,Southwestern Missouri

Abstract

Two rock and earth mounds in the Stockton Reservoir area provide data on two separate burial complexes previously unknownin thewestern Ozark Highlands. The Eureka Mound contained primary inhwnations with associations similar to those innearby Woodland and Mississippian mounds, but is unique in yielding a Caddoan water bottle of the Spiro Engraved type, and is dated about A. D. 1000-1450. This trade vessel, and Caddoan sherds from other sites in southwestern Missouri, provides leads to Caddoan contacts with groups in the Ozark Highlands. The Comstock Mound contained a single primary burial in a central pit associated with White trade goods which date around A.D. 1800. The mound may be of Osage Indian origin, but this identification is open to question because of transient Indian groups pas sing through the area about A. D. 1800.     

Shifting Trade Patterns as a Means of Reducing Global Carbon Dioxide Emissions

This article extends and applies the world trade model with bilateral trade (WTMBT), a linear program with any number of goods, factors, and regional trade partners that determines regional production, bilateral trade patterns, and region-specific prices on the basis of comparative advantage by minimizing factor use. The model provides a consistent analysis of the global production system, representing geographical location at a regional level, region-specific technologies at a sector level, emissions from production, and resource constraints and costs. An illustrative analysis investigates how changes in the geographic distribution of production could contribute to reducing global carbon dioxide (CO₂) emissions and at what cost. The model provides a bridge between global objectives and their determinants and consequences in specific sectors in individual regions. Multi-objective analysis is used to construct a trade-off curve between global factor costs and CO₂ emissions. The relevance of both primal and dual solution variables is demonstrated. In particular, changes in goods prices and emissions are investigated. We conclude that the main impact of tightening carbon constraints is a substantial reduction in international trade accompanied by a shift away from regions most reliant on the combustion of coal. In addition to the analysis of the overall global trends, including the impact on prices, the implications of the global carbon constraint for one specific industry are investigated.     

Local,regional and global markets: what drives the tuna fisheries?

Tuna products are amongst the most popular seafoods in the world and widely traded across the globe. Their global trade developed at a very early stage in the growth and development of tuna fisheries. In this article, recent evolutions of tuna markets in terms of products (for both sashimi and cannery-grade tuna products), market structures, and trade are introduced followed by a comprehensive study of global integration through price linkages. Most studies show a high degree of market integration and competition through prices at the world-wide level. Finally, we introduce some original results about the relationship between catches and prices (estimated coefficients of demand elasticity and flexibility), and provide answers to a few key questions for tuna fisheries and markets, including: How do consumers respond to price changes? Are fish price changes fully transmitted to consumers? Is there any economic incentive for fishers to comply with reduced catch quotas? Do fishers target particular tuna species according to the relative price of tuna species?     

Archaeobotanical evidence for trade in hazelnut (Corylus sp.) at Middle Bronze Age Kültepe (c. 1950–1830 b.c.), Kayseri Province,Turkey

Archaeobotanical samples from the Middle Bronze Age (MBA; c. 2000–1700 b.c.) city of Kanesh, excavated at the site of Kültepe in Kayseri Province, Turkey, preserve the charred shells of hazelnut (Corylus sp.). Hazelnut species do not naturally grow in the Kayseri area, being a native element of the broadleaf woodlands of Turkey’s Black Sea region, today home to a multi-million dollar international hazelnut export industry. The finds come from both the upper and lower city, being restricted to the Middle Bronze Age Karum level II, an occupation phase which saw the greatest development of the Assyrian trade network of which Kanesh was the administrative centre. This archaeobotanical discovery at Kültepe provides the earliest direct evidence for trade in hazelnuts in the region, probably imported on a small scale as luxury items facilitated by the Assyrian trade network. It also provides independent support for historical claims that hazelnut was traded at Kanesh based on the analysis of cuneiform tablets.     

广州市花地湾市场龟鳖类调查

通过对广州市花地湾花鸟鱼虫市场贸易龟鳖类进行为期3年27次调查,共记录了9科29属41种或亚种,包括鳖科(Trionychidae)2属2种,两爪鳖科(Carettochelyidae)1属1种,龟科(Emydidae)4属5种,淡水龟科(Geoemydidae)10属18种,侧颈龟科(Chelidae)3属3种,动胸龟科(Kinosternidae)2属3种,鳄龟科(Chelydridae)2属2种,陆龟科(Testudinidae)4属6种,海龟科(Cheloniidae)1属1种。其中,国内龟鳖类共13种,外来物种共28种。受保护种类30种,所占比例达73.17%,部分龟类来源为野外捕捉。大量实体商家转入互联网进行精确营销,尤其是针对高价值的濒危种类,未来将着重对该隐蔽领域进行深入调查。     

生态系统综合评价的内容与方法

生态系统综合评价是系统分析生态系统的生产及服务能力,对生态系统进行健康诊断,做出综合的生态分析和经济分析,评价其当前状态,并预测生态系统今后的发展趋势,为生态系统管理提供科学依据。从总体上讲,综合评价更强调生态系统一系列产品与服务功能之间的权衡,具有很强的实践意义。许多学者对不同的生态系统服务功能进行了经济价值评估,但缺乏对生态系统的产品、服务、健康与管理之间关系的进一步探讨。对生态系统服务功能评价、健康评价的生态管理与预测进行了系统论述,目的是提出生态系统综合评价的框架,指导生态系统评价行动及生态系统管理。     

Skeletal evidence for the emergence of infectious disease in bronze and iron age northern Vietnam

Human skeletal evidence for the emergence of chronic infectious disease in northern Vietnam is examined. The sample includes the remains of 192 individuals representing the Mid-Holocene and Bronze to Iron Ages. The objective is to see if the transition from sedentary, foraging, coastally oriented economies to centralized chiefdoms with attendant development and intensification of agriculture, trade, metal technologies, warfare, and population increase was accompanied by an emergence of and/or increase in infectious disease. It was found that skeletal evidence for infectious disease was absent in the Mid-Holocene, while over 10% of the Metal period sample exhibited lesions consistent with either infectious disease or immune system disorders. Factors potentially contributing to the emergence of infectious disease in northern Vietnam in the Metal period include: increased contact with bacterial or fungal pathogens either directly or by way of vertebrate and/or arthropod vectors; higher levels of debilitation and/or decreased levels of immunocompetence in the Metal period; and evolution of pathogens present in Mid-Holocene human hosts into more virulent forms in the Metal period. The first two factors may be related to historically and archaeologically documented major demographic (Han colonizing efforts) and economic (agricultural intensification) changes in the region during the Metal period.