WINGS Fellow Polly Wiessner was elected to the prestigious National Academy of Sciences for her lifelong work among the Kalahari bushmen of Botswana and Namibia, focusing on how they use large social networks with mutual obligations to survive in the harsh southern African desert landscape. And for 30 years, she has studied the Enga tribes highland horticulturalists in Papua New Guinea, with a focus on  20 years of warfare that began in 1990 when the tribes got shotguns and rifles, and the ultimate restoration of peace by clan and church leaders using outdoor village courts.