1: Phylogeny & Cladistics Flashcards
Define taxonomy
The discipline of naming and categorizing organisms, based on shared traits
Who created/standardized the Binomial Naming System?
Carolus Linnaeus
Define phylogeny
The evolutional history of a species or group of related species
What is the function of phylogenetic trees?
Diagrams the evolutionary relationships between organisms
Define systematics
A discipline that classifies organisms and determines their evolutionary relationships
What are some ways that systematists use to infer evolutionary relationships?
- Fossils
- morphological data
- biochemical data (proteins)
- genetic data
In a phylogenetic tree, what is the function of a branch point?
Represents the divergence of two species from a common ancestor
Define taxon
A type of group - like a species, family, or class
Define sister taxa
Groups that share an immediate common ancestor
What is a rooted tree?
A phylogenetic tree that includes a branch that represents the last common ancestor of everyone on the tree
Define outgroups
A group that is more distantly related to the other groups serving as reference
Define a polytomy
A branch where more than two groups diverge, creates an unknown level of closeness
Define homologies
Phenotypic and genetic similarities due to shared ancestry
A phylogeny must show similarities due to _______
Homology
What is the difference between homology and analogy?
Homology: Common ancestor, in structures they are similar but different function
Analogy: No common ancestor (convergent evolution), in structures they are different but similar function
Define clades/a clade
Clades are groups of related species, while a clade is a group of species that includes an ancestor and all its descendants
Define cladistics
Classifies organisms into groups by common descent
Define monophyletic groups
Consists of an ancestral species and all of its descendants
Define paraphyletic groups
Consists of an ancestral species and some of its descendants
Define polyphyletic groups
Consists of an ancestral species and its descendants plus members not apart of the group
What is a shared ancestral character?
A trait that originated from an ancestor
What is a shared derived character?
A trait in a clade that is not found in the ancestor
