The Tree of Life: Understanding Phylogeny

These flashcards cover key vocabulary and concepts related to phylogenetics, including definitions and explanations of fundamental terms and principles.

Phylogenetic tree

A diagram that depicts the evolutionary relationships among various biological species based on their shared ancestry.

Homoplasy

Character state similarity not due to common descent; includes convergent evolution and evolutionary reversal.

Parsimony

The principle of preferring the phylogenetic tree that requires the fewest evolutionary changes to explain observed data.

Exaptation

The evolutionary process where a trait or feature that initially carries out one function is later co-opted for a new function.

Consensus tree

A single tree that combines both the resolved and unresolved portions of a phylogeny.

Polytomy

An internal node of a phylogeny with more than two branches.

Character

A heritable aspect of organisms that can be compared across taxa.

Convergent evolution

Independent evolution of similar traits in separate lineages.

Evolutionary reversal

Reversion back to an ancestral character state.

Tetrapods

Vertebrates with four limbs, including mammals, birds, reptiles, and amphibians.

Character state matrix

A table used to develop phylogenetic trees that indicates whether a character is ancestral or derived.

Taxonomy

The science of classification of living organisms, including species grouping based on shared characteristics.