This research illustrates the efficacy of a new approach for collecting and analyzing family conversational data at museums and other informal settings. This article offers a detailed examination of a small data set (three families) that informs a larger body of work that focuses on conversation as methodology. The dialogic content of this work centers on biological themes, specifically adaptation. The biological principle becomes visible when families talk about survival strategies such as breeding or protection from predators. These themes arise from both the family members and the museum exhibit. This study also analyzes the inquiry skills families use as they make sense of science content. I assume that children and adults offer different interest areas or expertise for dialogic negotiation and that family members use inquiry skills in dialogue to explore matters of importance. This analysis offers educators methodological tools for investigating families' scientific sense-making in informal settings. © 2003 Wiley Periodicals, Inc. J Res Sci Teach 40: 138–162, 2003