Phylogenies Class Lecture Vocabulary

Vocabulary flashcards based on the class lecture covering phylogenies, taxonomic classification, evolutionary history, and phylogenetic tree terminology.

Synapomorphy

A shared evolutionary derived trait.

Heterotroph

A living organism that cannot make its own food and therefore eats others like a freeloader.

Autotroph

An organism that makes its own food using energy from the environment.

Homoplasy

A shared physical or genetic trait that appears in different species but not from a common ancestor.

Homology

A shared physical or genetic trait in different species from a common ancestor.

MRCA

Most recent common ancestor.

Derived state

A novel trait evolved from an ancestral form that appears in a lineage.

Lineage

A continuous sequence of organisms connected by a common ancestor.

Ancestral state

The original trait present in a common ancestor before any evolutionary changes in descendants.

Monophyletic

A group of organisms that contains a single common ancestor and all of its descendants (clade).

Paraphyletic

A group of organisms that contains a single common ancestor but not all of its descendant lineages (grade).

Polyphyletic

A group of organisms that share similar traits but do not share a recent common ancestor in the grouping.

Clade

Also known as a monophyletic group.

Grade

Also known as a paraphyletic group.

Parsimony

The principle that explanations that are simple are often correct (simplest explanation is usually the correct one).

Phylogeny

A hypothesis about how species evolved based on DNA, shared characters, and fossil evidence, describing relationships between species, genera, etc.

LUCA

Last Universal Common Ancestor from which all life descended.

Binomial method

The current means of naming an organism originating with Carolus Linneaus in the early 1700s, composed of three components: Genus, Specific epithet, and Authority.

Node

A point on a phylogenetic tree where branches connect, representing a speciation event.

Branch

A line on a phylogenetic tree connecting nodes or leading to leaves, representing evolutionary lineages over time.

Taxonomy

The field used to describe speciation events and evolutionary relationships through nomenclature.

Phylogenetic Tree Structure

A diagrammatic representation of evolutionary history across evolutionary time, showing a root, nodes, branches, and leaves.