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Non-dominated Sorting Genetic Algorithm-II

    This code is implements the nondominated sorting genetic algorithm (NSGA-II) in the R statistical programming language. The function is theoretically applicable to any number of objectives without modification. The function automatically detects the number of objectives from the population matrix used in the function call. NSGA-II has been applied in ARS research for automatic calibration of hydrolgic models (whittaker link) and economic optimization (whittaker link).

    Varroa Pop

      Varroa Pop simulates the growth of Varroa mite population in honey bee colonies. The program demonstratres how Varroa mites influence colony population growth throughout the year. You can change many factors through the menus in the model such as the initial population size, queen egg laying potential, and mite reproduction rates, so you can see how these factors influence both colony and mite population growth. We hope that the model will help you understand the interactions between the honey bee and mite populations and provide insights on how best to control Varroa in colonies.

      Data from: Defensive aphid symbiont Hamiltonella defensa effects on Aphelinus glycinis and Aphelinus atriplicis

        *Aphelinus glycinis* was collected in the Peoples Republic of China under a Memorandum of Understanding between their Ministry of Agriculture and the United States Department of Agriculture (USDA). *Aphelinus atriplicis* was collected by employees of the USDA, Agricultural Research Service (ARS), in the Republic of Georgia with the permission of that government. The parasitoids were imported into the USDA, ARS, Beneficial Insect Introductions Research Unit containment facility in Newark, Delaware, under permits from the USDA, Animal and Plant Health Inspection Service (Permit Numbers P526P-08-02142 and P526P-09-01929). No specific permissions were required to collect *Aphis craccivora* or *Acyrthosiphon pisum* because these are cosmopolitan aphids that occur in the field throughout North America. None of the species collected or studied are endangered or protected.