Phylogenetics and Tree of Life

A series of flashcards covering key vocabulary and concepts related to phylogenetics and the tree of life.

Phylogenetics

The study of the evolutionary relationships among biological entities, often using phylogenetic trees.

Monophyletic group

A group that includes all the descendants of a common ancestor.

Polyphyletic group

A group that does not include its common ancestor.

Paraphyletic group

A group that does not include all the descendants of a common ancestor.

Synapomorphies

Shared, derived characters used to build phylogenetic trees.

Homoplasies

Similar traits that arise through convergent evolution or evolutionary reversals, not useful for constructing phylogenies.

Convergent evolution

When superficially similar traits evolve independently in different lineages.

Evolutionary reversal

When a derived character reverts back to an ancestral state.

Molecular clock

A method that uses the average rate of nucleotide substitution to estimate the time of divergence between species.

Parsimony in phylogenetics

The principle stating that the simplest explanation, with the fewest character changes, is preferred when constructing phylogenies.

Ancestral characters

Traits that were present in a common ancestor.

Derived characters

Traits that have evolved from an ancestral character.

Homologous traits

Traits shared among species that were inherited from a common ancestor.

Molecular characters

Characters derived from molecular sequences (e.g., DNA) used in phylogenetic analysis.

Morphological characters

Physical characteristics used to build phylogenies, including structure and shape.

Behavioral characters

Behavioral traits that are heritable and can be used as valuable characters for phylogenetic studies.

Developmental characters

Traits related to the development of an organism that can help clarify evolutionary relationships.