Abstract: The eco-evo-devo of social insects addresses long-unanswered questions in Myrmecology, especially how novel castes originate and evolve. While this is an emerging field of broad interest to myrmecologists, German scientists prior to 1960 were quite active in studying such questions, but their attempts have largely been forgotten. The collective amnesia is partly because these papers are written in German and therefore inaccessible to the non-German speaking myrmecologists and partly because individual-level mechanistic approaches to studying social insects were eclipsed by population genetic approaches with the publication of Hamilton’s classic papers in 1964. Here, we present the first of a series of commentaries and translations of insightful papers written by German scientists before 1964 on the development of social insect castes as it related to colony function and social evolution. The goal of these translations and commentaries is to reveal findings and ideas that remain understudied to this day. Our first translation and com mentary is of two papers by Goetsch from 1937 and 1939 on caste determination and evolution in Pheidole ants and Anoplotermes termites.