Figure 6. Tardigrada family tree, showing physical appearance and hierarchical classification. This reminds students that behind
the branch of a phylogenetic tree is an actual living organism. Sometimes the simplicity of diagrams can be too abstract for
students and a more visually based image is needed.
Figure 7. Did tardigrades undergo horizontal gene transfer? A cartoon depicts the conflicting hypotheses. Teachers can use this
drawing by itself to focus on research papers that allude to horizontal gene transfer. Cartoons make for an easy entry point into a
research paper, as suggested in the dialogue between the velvet worm and the water bear.