Taxonomy & Systematics

Flashcards covering Taxonomy, Systematics, Phylogenetic Trees, Cladistics, Molecular Clocks, and Horizontal Gene Transfer.

Taxonomy

Science of describing, naming, and classifying living and extinct organisms and viruses.

Systematics

Study of biological diversity and the evolutionary relationships among organisms, both extinct and modern.

Phylogenetic tree

Diagram that describes phylogeny and represents a hypothesis of evolutionary relationships.

Phylogeny

Evolutionary history of a species or group of species.

Anagenesis

Single species evolves into a different species.

Cladogenesis

A species diverges into two or more species.

Node

The most recent species from which two different species evolved.

Root

Common ancestor for all members of the phylogenetic tree.

Branch

Connections and pathways in a phylogenetic tree.

Leaves

Living taxa at the tips of branches in a phylogenetic tree.

Monophyletic Group/Clade

A group consisting of a common ancestor and all of its descendants.

Paraphyletic Group

Contains a common ancestor and some, but not all, of its descendants

Homology

Similarities among various species that occur because they are derived from a common ancestor.

Convergent evolution

Traits arising independently due to adaptation to similar environments.

Cladistics

Compares homologous traits (characters) that exist in two or more character states.

Symplesio-morphy

Shared ancestral character.

Synapo-morphy

Shared derived character, shared by two or more species or taxa and originated in their most recent common ancestor.

Ingroup

Group we are interested in when using the cladistic approach.

Outgroup

Species or group of species that is assumed to have diverged before the species in the ingroup.

Principle of Parsimony

The simplest explanation or hypothesis is preferred.

Molecular Clocks

If neutral mutations occur at a constant rate they can be used to measure evolutionary time.

Horizontal Gene Transfer

Process in which an organism incorporates genetic material from another organism without being the offspring of that organism.

Taxonomy

Science of describing, naming, and classifying living and extinct organisms and viruses.

Systematics

Study of biological diversity and the evolutionary relationships among organisms, both extinct and modern.

Phylogenetic tree

Diagram that describes phylogeny and represents a hypothesis of evolutionary relationships.

Phylogeny

Evolutionary history of a species or group of species.

Anagenesis

Single species evolves into a different species.