Phylogenetic trees

Phylogenetics describes

The history of descent from common ancestry

Phylogenetics is used to

1) Determine which organisms are more closely related

2) Estimate when species formed

Node

Taxonomic unit

Rooted trees

Show common ancestor, direction of each path to each node corresponds to time

Unrooted trees

Only specifies relationship, not evolutionary path between nodes, they do not depict time or a common ancestor

Clades

Parts of the phytogenic tree including an ancestral node and all their descendants

Monophyletic group

A clade that contains a single common ancestor and all of their descendants

Paraphyletic group

A monophyletic group that excludes one or more descendants of the common ancestor

Cladogram

Illustrates evolutionary relationships among different species or groups

Phylogram

Type of phylogenetic tree that represents evolutionary relationships with branch lengths proportional to the amount of evolutionary change

Orthology

The condition where genes in different species are derived from a common ancestral gene through speciation events

Paralogy

The relationship of 2 homologous genes that have arisen from a duplication event

Bootstrap

A statistical method used to estimate the reliability of phylogenetic trees by resampling data and assessing how often specific clades appear