To Örebro University

Central to evolution is the concept of a common ancestry from which all life has emerged over immense time scales, but learning and teaching temporal aspects of evolution remain challenging. This study investigated students’ interpretation of evolutionary time when engaging with a multi-touch tabletop application called DeepTree, a dynamic visualization of a phylogenetic tree. Specifically, we explored how interactive finger-based zooming (zooming “in” and “out”) influenced students’ interpretation of evolutionary time, and how temporal information and relationships were conceptualized during interaction. Transcript analysis of videotaped interview data from ten secondary school students while they interacted with DeepTree revealed that zooming was interpreted in two ways: as spatially orientated (movement within the tree itself), or as time-orientated (movement in time). Identified misinterpretations included perceiving an implicit coherent timeline along the y-axis of the tree, that the zooming time duration in the virtual tree was linearly correlated to real time, and that more branch nodes correspond to a longer time. Sources for erroneous interpretations may lie in transferring everyday sensory experiences (e.g., physical movements and observing tree growth) to understanding abstract evolution concepts. Apart from estimating the occurrence of dinosaurs, DeepTree was associated with an improvement in interpretation of relative order of evolutionary events. Although highly promising, zooming interaction in DeepTree does not facilitate an intuitive understanding of evolutionary time. However, the opportunity to combine visual and bodily action in emerging technologies such as Deep Tree suggests a high pedagogical potential of further development of zooming features for optimal scientific understanding.