<p>Knowledge gaps in fundamental aspects of biodiversity are referred to as shortfalls, which have profound implications for scientific research, resource management, species conservation, and zoonotic disease surveillance. Seven main proposed shortfalls pinpoint knowledge gaps for taxonomic diversity, geographic distribution, population dynamics, evolutionary relationships, abiotic tolerances, biotic interactions, and biological traits of species. However, there is a knowledge gap that has not yet been addressed by these shortfalls, representing one of the most important components of biodiversity with implications for human well-being and species conservation: the zoonoses. Here, we introduce the concept of the Chagasian shortfall, which refers to our insufficient knowledge of pathogens, reservoirs and/or hosts, vectors, and, most importantly, epidemiological cycles, making it difficult to understand how zoonotic diseases spread across different dimensions. This shortfall represents a new perspective and the first step toward exploring the limits of biodiversity knowledge directly related to the One Health approach.</p>