The tree of life on this site
The phylogenetic tree of life available on this site serves to provide the visitor with an easy-to-follow route through the major groups of organisms, and the branching sequences between them. The lowest taxonomic level on this tree, and therefore the root, is Metazoa. The majority of this tree is a basic framework of how groups of organisms are related, but certain branches are extended as an example of how the tree proceeds to higher taxonomic groups. For example, the Insectivora are one of 18 traditional orders of placental mammals, and are used as the primary example of branching at a higher taxonomic level in this tree. Due to the potential size of a complete tree of life including all species past and present, this tree currently comprises only extant taxa, with a few major extinct groups included.
How to navigate through the tree
To navigate through the tree simply click on any highlighted branch leading from a group of organisms (e.g., Arthropoda) to see how that group bifurcates into finer branches. From there, click on another branch or group to follow the proposed evolution further. To return to the previous page of the tree simply click on the 'back' buttton or on the returning highlighted branch. Only the latinised scientific names label the tree's taxa, but the common names of the taxa on that page are listed on the right hand side of the tree.
Most of the branches terminate well before the ordinal level. This is because in its present form the tree is only basic framework, but as future Edinburgh University zoology students complete suitable projects their work will be added and linked to the tree, thus allowing a gradual blossoming of the tree. As an example, currently following the tree through to the mammals and then to the Eulipotyphla (traditionally Insectivora) will illustrate how the tree operates at higher levels.