While previous classroom studies of status hierarchies tell us who has low status and how to increase those learners' participation in small group contexts via teacher-led interventions, we know little about how one becomes low status, or the role peers play in legitimating or delegitimating inequitable relations. This study used the sociocultural concept of marginal non-participation to describe interactional moves learners use to navigate status hierarchies in an inquiry science context where student authority may permit learners to obstruct peers' participation. Participants were three collaborative groups of 3-4 learners in 7th grade science classrooms where a series of inquiry curriculum units were being implemented. Interviews were used alongside a microgenetic analysis of video-recorded group work observations to identify interactions that legitimated and delegitimated status hierarchies. Legitimation involved communicating acceptance of differential belonging and competence while delegitimation involved challenging differential reward by fostering widespread participation. Low- and high-status group members were active in both processes. Results suggest that diffuse status characteristics and science capital inform how status hierarchies are negotiated and that learners adapt disciplinary norms for status legitimating and delegitimating ends. Implications for learners' participation in scientific practices and identification with science are discussed.