Maria Helena Pereira Toledo Machado is Full Professor of History at the University of São Paulo, Brazil, researcher at the Brazilian National Research Council, and the author of numerous books and articles about slavery, abolition, and race in nineteenth-century Brazil, including Brazil through the Eyes of William James: Letters, Diaries, and drawings, 1865-1866 (2006 and 2010 Portuguese edition) and (T)Races of Louis Agassiz: Photography, Body, and Science, Yesterday and Today (2010 and reissues). She is now collaborating with the Haitian-Swiss artist Sasha Huber on an exposition of the Racial Photographic Collection of Louis Agassiz in Power Plant Contemporary Art Gallery in Toronto. Recently she is working on gender, slavery and post emancipation era. Her recent works focus on the impact of Free Womb Law of 1871 on the lives of slave and freed women, having co-edit the book “Ventres Livres. Gênero, Maternidade e Legislação, published in Sept/2021. She is now writing the book “Geminiana e seus filhos” which revolves around the murderer of two small slave children in Maranhão of 1876.