what is an evolutionary tree
A phylogenetic tree or evolutionary tree is a branching diagram or  tree  showing the inferred evolutionary relationships among various biological species or other entitiesâtheir phylogeny âbased upon similarities and differences in their physical or genetic characteristics.his is normally done by including an outgroup in the input data so that the root is necessarily between the outgroup and the rest of the taxa in the tree, or by introducing additional assumptions about the relative rates of evolution on each branch, such as an application of the molecular clock hypothesis.