BIOLOGY Introduction to Taxonomy The affinities of all the beings of the same class have sometimes been represented by a great tree... As buds give rise by growth to fresh buds, and these if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications. Charles Darwin, 1859
Transcript
BIOLOGY
Introduction to Taxonomy
The affinities of all the beings of the same class have sometimes been represented by a great tree... As buds give rise by growth to fresh buds, and these if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications.Charles Darwin, 1859
Taxonomy
Imagine two scientists . . .
One is from the United States and the other is from Germany
Both studying this organism
English: Hippopotamus German: Nilpferd
(translation, Horse of the Nile)
Taxonomy
The creation of a universal language for scientists so that (regardless of language or dialect) precise naming for organisms will occur
Latin was the selected universal language
Hippopotamus amphibus
Notice how this is written.
Genus capitalized,
species lowercase, in
italics
Taxonomy
Taxonomy is the science of grouping organisms based on their evolutionary similarities. Taxonomists analyze shared characteristics to determine evolutionary relationships between species.
Aristotle
Aristotle was the first person to attempt to classify things. He grouped everything into two groups; plants and animals. This system survived for nearly 2,000 years despite many mistakes. There was not an understanding of the microscopic world.
Carolus Linnaeus
In the 1700’s, a Swedish naturalist named Carolus Linnaeus designed a new system of classification in which every organism had a unique name.
He grouped organisms with similar structures together as a species. He also classified similar species into a group called genus. Every organism had a scientific name.
Linnaeus is known as the Father of Taxonomy
Categories of Classification
The organization for the taxonomy of organisms falls into eight levels.
Domain Does Kingdom King Phylum Phillip Class Chews Order On Family Fat Genus Green Species Stems
The closer the evolutionary link between two organisms, the closer they will be placed taxonomically. Only members of the same species can interbreed and produce fertile offspring.
Categories of Classification
Humans are classified in the following way:
Domain – Eukarya Kingdom – Animalia Phylum – Chordata Class – Mammalia Order – Primate Family – Homonidae Genus – Homo Species – Sapien
Binomial Nomenclature
Classifying organisms is important because it:
1) Eliminates confusion caused by name differences in various regions
ex) The cougar, puma, panther, and mountain lion are all the same organism
2) All scientists will use the same language (Latin).
3) Organizes vast amounts of information.
4) Reveals evolutionary relationships.
Rules for Writing a Scientific Name
The scientific name of an organism is comprised of two words;the genus and the species name.
1) Genus name always comes first and is capitalized (Homo)
1) Species name comes second and is NOT capitalized (sapien)
Both names are either underlined or italicized (Homo sapien)
Common NameCommon Name Scientific NameScientific Name
• Unicellular• Prokaryotic (no nucleus)• Some photosynthesize/others don’t• Ecologically diverse
Domain Archaea
Unicellular Prokaryotic Live in extreme environments (volcanic hot
springs) Many can survive only in the absence of
oxygen Cell membranes contain unusual lipid not
found in any other organisms
Domain Eukarya
All organisms that have a nucleus Corresponding to kingdoms:
Fungi Plantae Animalia “Protista”
Kingdom Protista
EukaryoticMostly unicellular, some colonial (live in a group)All eukaryotes that don’t fit in the other kingdomsExample organisms: ameoba, and paramecium
Kingdom Fungi
EukaryoticMostly multicellularCell wallHeterotrophs (other–feeder)Secrete digestive enzymes into their food source,
and then absorb the small molecules into their bodies!
Example organisms: molds, mushrooms, and yeasts
Kingdom Plantae
EukaryoticMulticellularCell wallNonmotile (can’t move)Autotrophs (self–feeder)Photosynthetic – use energy from sunlight to
make their own foodExample organisms: green algae, mosses, ferns,
