In the 1870s and 1880s, Francis Balfour and his students had shown that embryology could help to answer questions about the evolution of species. No one had studied the embryology of "Polypterus". Someone who could do this might prove the “missing link” theory and be greatly honoured, but it could be a dangerous quest. The only breeding "Polypterus" specimens were in swampy parts of African rivers. Africa was a turbulent place and swamps were rich breeding grounds for mosquitoes carrying malaria.