In this activity, students use linguistic data (word similarities between languages) to reconstruct a phylogenetic tree of related languages using a specific method called “Unweighted pair group method with arithmetic mean” (UPGMA). Students will use the tree to infer the specific relationships between languages, i.e. which ones are more closely related by sharing a more recent common ancestor. Students can then also reflect on the similarities and differences between biological and cultural evolution, or on the relationship between the fields of history and linguistics etc.