TAXONOMY

Terminology

Taxonomy: science of describing, naming, and classifying organisms

Taxon: particular group within a taxonomic system

Aristotle Classified organisms into

2 taxa (plants and animals)

Animals classified by living on land, sea, or in the air

Plants classified by stems

Organisms were discovered that did not fit into the groups, became recognized as an inadequate system

LINNAEAN SYSTEM Carolus Linnaeus

Devised system of classification according to form and structure of organisms (2 kingdoms- plants and animals)

Traits are heavily influenced by genes, providing clues to common ancestry

Each category represented a level moving from larger general to smaller more specific classification

LEVELS OF CLASSIFICATION

HIERARCHICAL CLASSIFICATION

Domain Kingdom Phylum Class Order Family Genus Species

Duuuuude King Philip Came Over For Green Soup

An example… General to specific

classification categories

Domain- Eukarya

SPECIESMembers of same species are:

morphologically similar able to produce fertile offspring

Binomial Nomenclature Genus name followed

by the species identifier Written in italics with

genus name capitalized Subspecies: variations

of a species living in different geographic areas Name follows the

species identifiers Ex. Orcinus orca

latirostris

SUBSPECIES

MEMBERS OF DIFFERENT SPECIES CAN INTERBREED, BUT . . .

THEY PRODUCE STERILE OFFSPRING!

Duh – it’s only, like, my favorite animal.

Phylogenetics: analysis of evolutionary or ancestral relationships among taxa

Phylogenetic TreesShow how closely

related taxa are to one another

Systematics

MODERN CLASSIFICATION

Similarities in…MorphologyFossilsEmbryosChromosomesMacromolecules

CLADISTICS

Clade: group of organisms that includes an ancestor plus all of it’s descendants

CLADOGRAM

Shared Character: Feature that all members of a group have in commonExamples: mammals=hair, birds=feathers

Derived Character: feature that evolved only within the group under consideration

http://www.youtube.com/watch?v=46L_2RI1k3k

Prokaryotes and Eukaryotes All organisms in each group not equally alike

Carl Woese Revised classification of Earth’s diversity from 6 kingdoms Grouped organisms based on rRNA sequences into domains

All living organisms (even prokaryotes) have ribosomes

Modern Classification

3 DOMAINS Bacteria

Small single celled organisms (prokaryotes) Archaea

Prokaryotes with unique biochemical and genetic properties Often inhabit harsh environments

Hot springs, thermal vents, salty lakes, etc. Believed to be among earliest organisms on Earth

Eukarya Eukaryotes

Plants, animals, fungi, single-celled organisms

Domain Bacteria: Kingdom Eubacteria“true bacteria”

Domain Archaea: Kingdom Archaebacteria“ancient bacteria”

DOMAIN EUKARYA Kingdom Protista

Classified by what they aren’t (fungi, animals, plants) Not very useful, several new taxa being considered Amoebas, paramecia, seaweeds, molds

Kingdom Fungi Absorb nutrients, not ingest (heterotrophic) Mushrooms, puffballs, rusts, mildews, molds]

DOMAIN EUKARYA Kingdom Plantae

Multicellular plants Most autotrophic, some parasitic Mosses, ferns, conifers, flowering plants

Kingdom Animalia Heterotrophic, multicellular, develop from embryos Symmetrical body organization

MISS FINN

Is awesome

don’t leave