Lec 2/3 Flashcards
Taxonomy
Discipline of naming organisms and placing them into a classification
Cladistic phylogenetic systematics
Discipline of discovering relationships among organisms and organizing them based on those relationships
(creating bins based off relationships)
Folk taxonomy
All languages simply had a name for an organism
These names can differ across cultures
Does not correspond to formal scientific classification
The Linnaean System
Hierarchical system where organisms were grouped together on the basis of similarity
Was refined over time
Taxons of the Linnaean system
Kingdom
Phylum
Class
Order
Family
Genus
Species
Linnaean Binomial
Genus (starting with a capital) followed by species (all lowercase) followed by brackets that contain the person who named the species and the year the species was named
Evolutionary taxonomy
Developed by several generations following Charles Darwin’s “Origin of Species”
Used Linnaean ranks, but introduced the idea that supraspecific taxa were groups of similar and related species
Supraspecific taxa
Taxa above the species level
Evolution taxonomy led to
The creation of the first traditional evolutionary tree
Traditional evolutionary tree
Taxa can be defined in terms of which parts of the tree they encompass
Cladistic (Phylogenetic) systematics four key principles in finding relationships
Evolutionary relationships are represented by a tree of diverging branches, with species at the tips
Supraspecific taxa are groups of closely related species, corresponding to major branches
To build a tree, species are grouped together based on shared derived features
Ancestors are never specified, but always treated as hypothetical entities corresponding to nodes
Group
Members of a clade
Clade
Branch on a cladogram
Phylogenetic Tree Vs Cladograms
Phylogenetic trees include time and depict hypotheses of evolutionary history while cladograms only concern about the relationship among taxa
Problems with Linnaean Ranks
Non-equivalence of ranked across taxonomic groups
Not enough ranks to accommodate every taxon biologists might want to discuss