What does the phylogenetic tree tell you about the evolutionary relationships of animals?
Phylogenetic tree reveals evolutionary relationships between different organisms, their common ancestor, and descendants.
Our knowledge on evolution of biodiversity could be illustrated easily by forming phylogenetic trees. Root of the tree represents ancestral population from which other organisms evolved. Nodes on the tree are branching points. Each branching point represents a time in the past when an ancestral population diverged from the rest, leading to evolution of a new organism. Terminals of the tree, at end of branches, represent different taxa.
By studying the phylogenetic tree we can compare the relative evolutionary closeness between different organisms.