Classifying Things Flashcards
What is systematics?
Systematics is the study of evolutionary realtionships.
What is phylogeny?
A diagram representing hypotheses about relationships among species or groups of organisms
What 5 things make up the tree structure?
- Taxa
- Branches
- Nodes
- Outgroup
- Root Node
What is taxa?
individuals, species, or groups
What are branches?
They connect taxa and represent evolution over time
What are nodes?
Nodes intersect two or more branches. They represent the most common ancestor and speciation events.
What is the outgroup?
A taxon group related to but not included in any of the taxa/groups represented in the tree.
What is the root node?
Node connecting taxa of interest to outgroup, MRCA of all taxa on the phylogeny
What is monophyly?
Group includes most recent common ancestor and all descendants.
What is paraphyly?
Group includes most recent common ancestor but not all of its descendants
What is polyphyly?
Group does not include most recent common ancestor of all members of the group.
What is cladistics?
A system of classifying organisms into groups based on shared derived characteristics.
What is a shared derived character?
A similarity that is inherited from a common ancestor of an entire group.
What are ancestral traits?
They are similarities that are inherited from a common ancestor, can be used as SDC’s in cladistics.
What are derived traits?
They are traits that arose more recently and are shared only by a subset of species.
