Chapter 26 Taxonomy and Systematics Flashcards
The science of describing, naming, and classifying species
Taxonomy
Species that still exist today are classified as…
extant
Species hat have died out are known as…
Extinct
All species are placed into progressively smaller hierarchical groups. A group at any level is called
Taxon
Today, all forms of life are groups into one of 3
Domains
The three domains
Archaea, Bacteria, and Eukarya.
After domains, there are seven groups that contain various types of protists.
Supergroups
within domain eukarya, there are three
Kingdoms
The remaining taxa (after kingdom) are (in order from most inclusive to least inclusive):
Phylum Class Order Family Genus Species
The standard method for naming species
Binomial nomenclature
The evolutionary history of a species or a group of species
Phylogeny
A phylogeny can be represented by a diagram called a…
phylogenetic tree.
The branch points in a phylogenetic tree are called
Nodes
a common ancestral species and all of its descendents.
A clade
A type of phylogenetic tree built on similarities and differences between organisms
Cladogram
A character that is shared by two or more different taxa and is present in the most primitive ancestor
Symplesiomorphy
A character that is shared by two ore more different taxa and is NOT present the most primitive ancestor (but is present in the most recent ancestor)
Synapomorphy
A group whose evolutionary relationships we wish to understand
Ingroup
The ingroup is compared to organisms who lack one or more shared derived characters found in the ingroup.
Outgroup
When one or more possible cladograms can be constructed, the hypothesis that should be used is the one that is simplest for all characters.
Principle of Parsimony
Phylogeny
Hypothesis of evolutionary history of organism, including which species are closely related and in what order species evolved.
Darwin’s idea of “descent with modification”
All organisms have an evolutionary history, and that shared traits among organisms.
Principle of Parsimony
Hypothesis that simplest explanation of history of evolution…organisms share ancestors of commonality.
Cladogram
A graphic representation of a proposed phylogeny.