Interpreting Phylogenetic Trees

Phylogenetics

The study of evolutionary relationships among groups of organisms

Roots

The term for the origin of a phylogenetic tree - represents the original (hypothesized) ancestor

Tips/Leaves

The term for the ends of the branches on a phylogenetic tree

Nodes

The intersection of two branches

Monophyletic group

All descendants of a common ancestor, including the ancestor

Paraphyletic group

Most, but not all descendants of a common ancestor, including the ancestor

Polyphyletic group

Unrelated organisms, excluding the common ancestor

Synapomorphy

Shared derived trait, defines a monophyletic group

Clade

Another name for a monophyletic group

Sister group

Closest relatives on the tree, share a common ancestor

Outgroup

Close relative, but not a member of the study clade