William Beinart is Emeritus Professor, St Antony's College, University of Oxford and former Director of the African Studies Centre. His publications include The Rise of Conservation in South Africa (2003), Environment and Empire (2007) with Lotte Hughes, Prickly Pear: A Social History of a Plant in the Eastern Cape (2011) with Luvuyo Wotshela, African Local Knowledge & Livestock Health (2013) with Karen Brown and Rights to Land (2017) with Peter Delius and Michelle Hay. Saul Dubow is Smuts Professor of Commonwealth History at the University of Cambridge. He is the author of books, edited collections, and articles about nineteenth and twentieth-century South African history including Scientific Racism in Modern South Africa (1995), A Commonwealth of Knowledge (2006), South Africa's Struggle for Human Rights (2012), and Apartheid 1948–1994 (2014). He is the editor of Science and Society in Southern Africa (2000).