Evolutionary relationship between the species used in the activity about systematic. (A) Evolutionary tree showing the relationship between the species used in the activity about systematic. Note that the figure only depicts some branches of the tree of life and branch lengths are not proportional to time. Numbers correspond to the following species: fern (1), southern maidenhair fern (2), pine (3), fir (4), tarantula (5), spider (6), butterfly (7), moth (8), codfish (9), pouting (10), cat shark (11), shark (12), salamander (13), newt (14), toad (15), Iberian frog (16), turtle (17), chelidae (18), wall lizard (19), lizard (20), stork (21), heron (22), chicken (23), pheasant (24), orangutan (25), human (26), bat (27), and mouse (28). (B) Representation of hierarchical grouping of a subset of the species allowing exploring the relation between phylogenetic and genealogical trees (left: a photograph taken during a class in an elementary school; right: schematic representation of the photograph).