This article explores how data-related reasoning naturally emerged during an ecological investigation, the strategies used to support students’ understanding, and how students navigated the challenges of integrating statistical reasoning with their scientific explanations. Students in a ninth-grade biology class explored why the populations of wildebeest and buffalo increased dramatically in the Serengeti between 1960 and 1975. In the process, they worked with three key data-related skills that were necessary for their inquiry: using proxy variables; interpreting scatterplots to determine if a correlation exists; and distinguishing between correlation and causation. Teaching tips for integrating data into science inquiry are included based on this classroom experience.