With the aim of exploring how science is done in collaborative interactions when children discuss reasons for animal diversity, this paper provides insight into the relationships between acts of doing science and collaborative interactions. Video data from four small-group discussions (N = 14) were analysed using Lemke's (1990) talking science framework and Granott's (1993) collaborative interaction framework. During their interactions, the children make use of their prior experiences and the materials provided as they engage in acts of doing science. The findings reveal that 6-year-old children are able to engage in science dialogue as they use observations and comparisons as data to generate, describe and discuss ideas. Moreover, while engaged in highly collaborative interactions, the children use observations to evaluate, challenge and question each other. Overall, the study sheds light on how acts of doing science can be perceived in young students' discussions about science phenomena. The study indicates that the character of the collaborative interactions is an important factor for how acts of doing science are carried out.