Phylogeny is the study of relationships between items (organisms, concepts, etc); typically represented by phylogenetic trees. Such trees may simply reflect evolutionary relationships; or their branches may be scaled according to some measure of evolutionary distance, such as accumulated mutations or time.
Phylogeny is the study of relationships between items (organisms, concepts, etc). The primary use of phylogeny is in systematics, the inference of evolutionary history from morphological and/or molecular data; this typically requires computational methods. Relationships are often depicted as trees, whose branches may scale according to an aspect of evolutionary distance, such as number of mutations, or time. When temporal and/or geographic data are available, phylodynamic or phylogeographic analyses can be performed.