General Biology: Phylogenetics Review

Flashcards covering key vocabulary and concepts in phylogenetics and evolutionary relationships.

Phylogenetic Tree

Branching diagram showing patterns of descent from a common ancestor; a hypothesis that may change with more data.

Unrooted Tree

A phylogenetic tree that shows relationships but does not show an ancestral root or starting point.

Rooted Tree

A phylogenetic tree where one branch represents the most recent common ancestor of all taxa on the tree.

Branch Points (Nodes)

Dichotomies or divergences of 2 images from a common ancestor; branches can rotate without changing relationships.

Extant Species

Species that are still alive or currently living, found at the tips of branches.

Basal Taxon

The first lineage to diverge from the common ancestor of a group.

Sister Taxa

Organisms that share an immediate common ancestor and are each other's closest relatives.

Polytomy

A branch point with 3 or more descendant groups, indicating unclear evolutionary relationships.

Analogous Structures

Structures in different species that perform a similar function but do not share a common ancestor (e.g., bird wings and honeybee wings).

Morphological Data

Anatomical features, developmental and life history traits used for choosing characters in phylogenetics.

Molecular Data

DNA sequences compared to determine relationships between organisms; genes are sees of 1005 of nucleotides.

Monophyletic Group (Clade)

A common ancestor and all of its descendants.

Paraphyletic Group

A common ancestor and some, but not all, of its descendants.

Polyphyletic Group

A group of distantly related species that does not include the most recent common ancestor.

Shared Ancestral Character

A character that originated in an ancestor common to all species in a clade.

Shared Derived Character

A character unique to a clade; originated in a ancestor.