Taxonomy and Systematics BIOL Lab Exercise 2

Taxonomy

The science of classifying and naming organisms.

Species

Any group of closely-related organisms that can interbreed and reproduce fertile offspring.

Population

Members of the same species isolated geographically into smaller groups.

Phylogeny

An illustration depicting a hypothesis of the evolutionary history of a group of organisms.

Taxon (Taxa)

A named classification unit to which individuals or sets of species are assigned (organisms at tips of branches).

Node

The speciation event that caused a divide into species (also shows recent common ancestor)

Monophyletic Groups (Clades)

A group that consists of a common ancestor and all of its descendants.

Why are Clades Meaningful?

Clades give us information about relationships based on descent from a common ancestor.

Shared Derived Character

A trait that two or more groups share because they inherited it from a common ancestor.

Topology

The branching pattern of a phylogenetic tree.

Homology

The study of likeness (from a common ancestor).

Homologous Structures

Structures of different species that have similar anatomical design due to a common ancestor (even if they serve different functions).

Analogous Structures

Structures of different species that serve similar functions but have different anatomical design due to different ancestors.

Convergent Evolution

Occurs when unrelated species develop similar traits due to similar environmental pressures.

Divergent Evolution

Occurs when related species develop different traits as they adapt to different environments.

Outgroup

Most distantly related organism that is used as a comparison to other organisms.

Hierarchical Classification

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Acronym For Hierarchical Classification

Dear King Philip Comes Over For Good Soup/Spaghetti

Serotype

a subgroup of microorganisms (bacteria or virus) within a species that share identical surface structures (called antigens)

Variant

genetic sequence differences in organisms that may have functional consequences

Domains of Life

Bacteria, Archaea, Eukarya

Binomial

a two-part name consisting of “genus” and “species” used to classify organisms.