chapter 18: taxonomy taxonomy: the discipline where scientists classify organisms and assign...
TRANSCRIPT
Chapter 18: TaxonomyChapter 18: Taxonomy
Taxonomy: the discipline where scientists classify organisms and assign universally accepted names to each organism.
I. Aristotle- 384-322 B.C.A. Devised “classical” system that lasted 2,000 years. “Scala naturae”= “great chain of being” plants man
A. Aristotle’s system had 2 Kingdoms.
1. Plant Kingdom
(trees, shrubs, herbs)
2. Animal Kingdom
(land, sea, air)
II. Carolus Linnaeus- botanist who lived in 18th Century. Developed binomial nomenclature system of naming; 7 category system of classification.
A. Problems with common names1. Misnomers
Ex. Jellyfish, silverfish, starfish, goldfish, crayfish
2. Variation in names among languages and regions (localities)
Ex. Cougar, puma, mountain lion
Jellyfish
Starfish
Silverfish
Crayfish
Only true fish…
Goldfish!
B. Developed scientific names1. Chose Latin: 18th Century scientists understood Latin.
2. Binomial nomenclature: Two-word naming system. 1st part: genus, 2nd part: species
A. Names based on1. Physical characteristics
Ex. Melanoleuca
2. BehaviorEx. Noctivagens
3. Honorary (for people- discoverer, someone of past significance )
4. Location and HabitatEx. Californica
C. Categories of classification1. Kingdom
Phylum (Division)
Class
Order
Family
Genus
Species
AnimalChordate
MammalPrimate
HominidHomo
sapiensYou must know the full classification for a human!
Animal-Chordate-Mammal-Primate-Hominid-Homo-sapiens
2. Genus species name is written in italics or underlined. Genus is capitalized, species is not.
Ex: Homo sapiens or Trifolium agarium
III.Modern TaxonomyA. Classification is based on similarities
1. Structures (morphology)
2. Biochemical and genetics
3. Evolutionary relationships (phylogeny)
4. Embryology
5. Reproductive potential
a. species= organisms that are “reproductively isolated and produce fertile offspring.”
*not man-made
IV.Six Kingdom SystemA. Plants: multicellular, eukaryotic (true nucleus), stationary autotrophsB. Animals: multicellular, mobile, eukaryotic heterotrophsC. Fungi: stationary heterotrophs, eukaryotesD. Protists: unicellular eukaryotes Monera: unicellular prokaryotesE. Archaebacteria– used to be called MoneraF. Eubacteria– used to be called Monera