The aim of this study was to identify the type of conceptual change (assimilation or accommodation) that can be induced by a refutational text. Individual interviews were carried out with a stratified sample of eighty-seven grade 9 students. Forty-four percent of them were found to have a misconception about the concept of ecological role - they believed that some living things do not have a role in nature. These 36 students were asked to read either a text that refuted the misconception, or a control text that consisted of a didactic explanation of ecological role. They then participated in an immediate posttest and a delayed posttest. Surprisingly, both texts were able to induce accommodation in a large proportion of the students. Factors such as the high motivation of the students, encouragement of metacognition, age-readiness of the students, and a relative lack of robustness of the misconception were considered to have greatly facilitated the conceptual change process.