Introduction to Phylogenetics

Flashcards covering key vocabulary and concepts related to phylogenetics, including definitions and explanations of important terms.

Cladogenesis

The branching of lineages in an evolutionary tree.

Anagenesis

The evolutionary change that occurs within a lineage from ancestors to descendants.

Phylogenetic Tree

A diagrammatic representation of the evolutionary relationships between groups of organisms.

Taxon (plural: Taxa)

A group of one or more populations of organisms that form a unit in our classification system.

Node

The point on a phylogenetic tree that represents the most recent common ancestor of the taxa above it.

Bifurcation

A point in a phylogenetic tree where a single lineage splits into two distinct lineages.

Speciation Event

A process through which new species arise.

Clade

A group of organisms that includes a common ancestor and all its descendants.

Monophyletic

A group that contains an ancestor and all its descendants.

Polyphyletic

A taxonomic group that does not share an immediate common ancestor.

Paraphyletic

A taxonomic group that shares a common ancestor but does not include all its descendants.

Homology

Traits in two or more taxa that were inherited from a common ancestor.

Homoplasy

Similarity in characteristics found in different species not due to common ancestry.

Outgroup

A taxon that is related to the group under study but branches off earlier, providing a point of comparison.

Synapomorphy

A derived character state shared by two or more lineages.

Sister Taxa

Two lineages that share a most recent common ancestor.

Character State

Different forms of a trait that can be used to classify organisms.