Phylogeny and the Tree of Life

These flashcards cover key concepts related to phylogeny and the tree of life, including definitions of important terms, classification systems, and evolutionary relationships.

Phylogeny

The evolutionary history of a species or group of related species.

Sister taxa

Groups that share a common ancestor that is not shared by any other group.

Basal taxon

A lineage that diverges from all other members of the group.

Binomial nomenclature

A system of taxonomy based on resemblances where the first part of the name is the genus and the second part is unique for each species.

Clade

A group of species that includes an ancestral species and all its descendants.

Homology

Similarity due to shared ancestry.

Analogy

Similarity due to convergent evolution.

Cladistics

A biogeographical classification that groups organisms based on common ancestry.

Molecular clock

An approach used to estimate the absolute time of evolutionary change based on genetic data.

Monophyletic group

A group consisting of an ancestor and all of its descendants.

Paraphyletic group

A group consisting of an ancestor and some, but not all, of its descendants.

Polyphyletic group

A group that includes distantly related species but not their most recent common ancestor.

Outgroup

A species or group of species closely related to, but not part of, the group being studied.

Shared derived character

An evolutionary novelty unique to a particular clade.

Shared ancestral character

A character that originated in an ancestor of the taxon.

Taxon

A group at any level of classification.

Hierarchical classification

A system of organizing biological diversity into a series of ranked levels.

Phenotypic similarity

Similarities in observable characteristics, often influenced by genetic similarities.