Final answer:
The statement that taxa are shown at the tips and the ancestor is represented by the root of a phylogenetic tree is true. A rooted tree shows relationships back to a single ancestral lineage, and a basal taxon refers to an early, unbranched lineage from the root.
Step-by-step explanation:
In a phylogeny, the statement that the taxa are shown at the tips and the ancestor is represented by the root is true. A phylogenetic tree is a diagram that represents evolutionary relationships among organisms. Branch points on the tree indicate where lineages diverge. If a lineage evolved early and remains unbranched from the root of the tree, this lineage is known as a basal taxon. When two lineages diverge from the same branch point, they are referred to as sister taxa. Phylogenetic trees that show where organisms relate to a single ancestral lineage are called rooted trees, which are contrasted with unrooted trees that do not indicate a common ancestor but still show the relationships between species. Polytony in a tree indicates that the exact evolutionary relationships among more than two lineages at that branch point have not been fully resolved.