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Genetic diversity in crop plants is crucial for long-term world food security. This diversity is sustained in the field primarily by poor farmers in developing countries, who receive no compensation for providing this external benefit to humankind. When agricultural imports displace local production in centers of genetic diversity, this threatens both rural livelihoods and the continued provision of this external benefit. The North American Free Trade Agreement's impact on Mexican maize farming illustrates the problem. The prospects for remedial policies are shaped by the distribution of the costs and benefits of action of inaction.

Ashraf and Galor (2012) advanced the bold thesis that genetic diversity within different human populations has been a foundational determinant of long-run economic development. We show that their results are not robust after controlling for a key missing variable - the Eurasia dummy. After controlling for the Eurasia dummy, all indicators of genetic diversity lose statistical significance in regressions with indicators of economic development as dependent variables. Ashraf and Galor's statistical results merely "reflect" - literally - Eurasia's unique advantage in supporting economic development that was mostly based on settled agriculture until about AD1500.

Ashraf and Galor (2012) advanced the bold thesis that genetic diversity within different human populations has been a foundational determinant of long-run economic development. In the HSR article "Eurasia Advantage, not Genetic Diversity: Against Ashraf and Galor's 'Genetic Diversity' Hypothesis," we show that their results are not robust after controlling for a key missing variable - the Eurasia dummy. After controlling for the Eurasia dummy, all indicators of genetic diversity lose statistical significance in regressions with indicators of economic development as dependent variables. Ashraf and Galor's statistical results merely "reflect" - literally - Eurasia's unique advantage in supporting economic development that was mostly based on settled agriculture until about AD1500. The appendices included in this volume of HSR Trans complement the following article: Shiping Tang, 2016, Eurasia Advantage, not Genetic Diversity: Against Ashraf and Galor's "Genetic Diversity" Hypothesis, Historical Social Research 41 (1): 287-327. doi: http://dx.doi.org/10.12759/hsr.41.2016.1.287-327.

Presents the views and work of 3 winners of the Right Livelihood Foundation awards. These are concerned with resistance to abuse with biotechnology, and to the malign effects of monoculture, with respect to developing countries.

This paper presents a model of nation formation in which culturally heterogeneous agents vote on the optimal level of public spending. Larger nations benefit from increasing returns in the provision of public goods, but bear the costs of greater cultural heterogeneity. This tradeoff induces agents' preferences over different geographical configurations, thus determining the likelihood of secession and unification. We provide empirical support for choosing genetic distances as a proxy of cultural heterogeneity. By using data on genetic distances, we examine the stability of the current map of Europe and identify the regions prone to secession and the countries that are more likely to merge. Our framework is further applied to estimate the welfare gains from European Union membership.

This paper presents a model of nation formation in which culturally heteroge- neous agents vote on the optimal level of public spending. Larger nations beneÞt from increasing returns in the provision of public goods, but bear the costs of greater cultural heterogeneity. This tradeoff induces agents preferences over different geo- graphical conÞgurations, thus determining the likelihood of secession and uniÞcation. We provide empirical support for choosing genetic distances as a proxy of cultural heterogeneity. By using data on genetic distances, we examine the stability of the current map of Europe and identify the regions prone to secession and the countries that are more likely to merge. Our framework is further applied to estimate the welfare gains from European Union membership.

This paper presents a model of nation formation in which culturally heterogeneous agents vote on the optimal level of public spending. Larger nations benefit from increasing returns in the provision of public goods, but bear the costs of greater cultural heterogeneity. This tradeoff induces agents? preferences over different geographical configurations, thus determining the likelihood of secession and unification. We provide empirical support for choosing genetic distances as a proxy of cultural heterogeneity. By using data on genetic distances, we examine the stability of the current map of Europe and identify the regions prone to secession and the countries that are more likely to merge. Our framework is further applied to estimate the welfare gains from European Union membership.

This paper presents a model of nation formation in which culturally heterogeneous agents vote on the optimal level of public spending. Larger nations benefit from increasing returns in the provision of public goods, but bear the costs of greater cultural heterogeneity. This tradeoff induces agents? preferences over different geographical configurations, thus determining the likelihood of secession and unification. We provide empirical support for choosing genetic distances as a proxy of cultural heterogeneity. By using data on genetic distances, we examine the stability of the current map of Europe and identify the regions prone to secession and the countries that are more likely to merge. Our framework is further applied to estimate the welfare gains from European Union membership.

The objective of this study is to determine the diversity and genetic structure of cowpea weevil populations in the different agro-ecological zones of Senegal. Thus, to achieve this objective, individuals of Callosobruchus maculatus from localities in each zone were used, after sampling and massive breeding. The sequenced gene is Cyt-B. The results showed high haplotypic diversity (0.901 ±0.00033) and low nucleotide diversity (0.010 ±0.0000003). These diversities studied by agro-ecological zone show that the Casamance zone has the greatest haplotypic diversity (0.901; P>0.05) while the eastern Senegal zone has the lowest value (0.439; P>0.05). The nucleotide diversity is lower in the Sylvo-pastoral zone (0.00112; P<0.05) and higher in the Casamance zone (0.01052; P<0.05). The genetic structuring shows that the Senegal River Valley-eastern Senegal zone couple is more differentiated [FST(Fixation index)]=0.70687; P<0.05) and the Casamance-Groundnut Basin zone couple is less differentiated (FST=0.21248; P<0.05). The greatest genetic distance was found between the Sylvo-pastoral zone and the River Valley and the smallest between the eastern Senegal zone and the River Valley. However, a significant genetic variation within the populations was noted (64.93%). Overall we have a low level of diversity and weakly structured populations except those of Tamba and Fouta. A slight influence of the zones was also noted.

Humans are only one of the species produced by the hominoid evolutionary radiation. Common and pygmy chimpanzees (our closest relatives), gorillas, orangutans, and the lesser apes also belong to this group. In humans, patterns of genetic variation are becoming increasingly better characterized by modern molecular methods. Understanding human variation in an evolutionary context, however, requires comparison of human patterns with those of other hominoids, to reveal features shared among hominoids and those unique to humans. Genetic variation among chimpanzees, gorillas, and orangutans is beginning to be characterized, so that comparisons are now possible. From genetic data, several different kinds of information can be reconstructed, including the evolutionary relatedness of subspecies and populations, time estimates for evolutionary divergences, past population dynamics, extent of gene flow over geographical landscapes, and group social structure. Knowledge of hominoid genetic variation is also relevant to applied fields such as primate conservation and medicine.