Since Darwin rode on the backs of the Galápagos giant tortoises, the archipelago and its unusual species have been central in understanding how environmental influences shape evolutionary development. Today, these fabled islands face a crisis that conservationists see as threatening the historic isolation that allowed for the development of endemic species like the giant tortoises. Most analyses situate this crisis in a Malthusian history of increasing developmental pressure over the past 30 years; however, I argue that adequately understanding current problems in the Galápagos requires a return to the annals of evolutionary science to analyze how this history has shaped the islands and their species. Using the giant tortoise as my focal point, I ask the overarching question: How do changing human conceptions of and interactions with nature shape evolutionary processes, and to what effect? Over the past 200 years, giant tortoises have been scientific curiosities, conservation icons, tourism commodities, and lightening rods of political protest. I use their story to situate the current crisis in intertwined histories of science, conservation, and development, which I argue have materially shaped social conflicts as well as the very nature of tortoises. To explore this claim, I look at these three paradigms of human-environment relations across three key historical moments in the Galápagos: Darwin’s visit in 1835, the founding of the Galápagos National Park (GNP) in 1959, and recent crisis declarations. This interdisciplinary project combines archival research at UNESCO and natural history museums with ethnographic research on three tortoise conservation projects in the Galápagos. This work is informed by theories of the social production of nature as well as developmental biology that sees evolution not as strictly biological, but as a process in which by ecological and social influences shape the conditions of possibility for an organism's development.