Evolution has been positioned at the centre of conflict between scientific and religious explanations of the workings of the world. However, little research has examined other possible reasons for some people rejecting scientific explanations. The author's research indicates that for some people, irrespective of faith, the ideas associated with evolution can be potentially disturbing: ideas about change, uncertainty, absence of purpose, extinction and struggle, as well as identity. The affective dimension of teaching and learning about evolution needs to be taken into account and our classrooms should provide safe places for our students to discuss the personal implications of science.