The history of the science of time often focuses on the techniques and technologies that led to our present practices but neglects other approaches to timekeeping that were discarded, neglected, or peripheral to how we currently reckon time. Yet, there have been contexts in which multiple timescales coexisted, even if such instances of timescale pluralism have now been mostly forgotten. This presentation explores timescale pluralism and timescale uniformity in late medieval York, early modern Nuremberg, mid-twentieth century studies of the biting behavior of mosquitoes in Trinidad, and current primatology. These different cases reveal the benefits and pitfalls of timescale pluralism versus timescale uniformity and suggest a rethinking of the history of the science of time away from narratives that emphasize function and progress to those that explore politics, contested choices, and the conceptual costs of particular decisions.