13.4 VOCAB (Cladograms/Phylogenetic Trees)

Phylogeny

The evolutionary history of the relationships between common ancestors and organisms

Phylogenetic Tree

A map/diagram that draws out the evolutionary relationships and phylogeny

Lineage

A series that includes an ancestor and all of its offspring populations that is modeled by a line on a phylogenetic tree

Node

An event that splits a lineage on a phylogenetic tree into two.

Root

Location on phylogenetic tree where the common ancestor of all organisms in the tree is located

Most recent common ancestor

Common ancestor that can be used as the root of a phylogenetic tree

Clade

A taxon and ALL of its descendents from a common ancestor.

Systematics

Studying and classifying biodiversity

Tree of Life

A representational diagram that shows all evolutionary relationships between all species

Homologous Character

A feature shared between 2+ species both inherited from the common ancestor

Ancestral Trait

Traits that are shared by the common ancestor and it’s descendents

Derived Trait

New (mutated) traits in the recent ancestor that create a new lineage

Synamorphy

Traits shared through a group of organisms (shared derived trait)

Plesiomorphy

A trait that is shared by all descendents of an ancestor

Analogous Characters

Similar structures that can function but evolved independently of one another from the same ancestor

Evolutionary Reversal

An occurrence where a derived trait reverts to its ancestral state

Homoplasies

Traits that are caused by evolutionary reversal and convergent evolution

Outgroup

A group that is phylogenetically outside the ingroup

Parisomy

A principle that states essentially the simplest answer is the best answer

Molecular Clock

A hypothesis/idea that molecular change could be used to infer evolutionary divergence time

Biological Nomenclature

A naming system that uses the relatively same names to to name organisms.

Monophyletic Group

A group consisting of the ancestor and all of its descendents; not leaving anything out

Paraphyletic Group

A group that doesn’t have the ancestor included in it; leaving it out

Polyphyletic Group

A group that doesn’t include all descendents of an ancestor