Botswana, Africa’s oldest democracy, is Texas-sized but sparsely populated, with most of its territory being Kalahari Desert. Recent genetic sleuthing reveals every human descends from a single female living in Botswana’s geography 200,000 years ago. Though diamond mining drives Botswana’s modern economy, its pastoral culture dates from the time of Christ. “Down on the Farm” host Tom Willey and horticulturists Seoleseng Tshwenyane and Otsoseng Oagile discuss efforts to develop Botswana’s food self-sufficiency.