why classify? what’s in a name? in order to name and group organisms in a logical manner we must...
TRANSCRIPT
CHAPTER 18
Classification
Why Classify? What’s in a name?
In order to name and group organisms in a logical manner we must arrange them according to similarities and differences. Usually from physical characteristics or DNA/Protein sequencing.
Taxonomy- classifying organisms and assigning each a name – according to their characteristics, physical traits.Scientists that classify living organisms are called
Taxonomists.
Do you organize?
Think of your house:Is there a logical set up? Is it organized?Your clothes? Do you have them arranged
by season? By color? By style? School work, do you organize it by subject?
A day or B day? All of us organize in some way.
Choosing the arrangement by our personal needs and aesthetics.
Assigning Scientific Names Early Efforts- described physical characteristics
Carolus Linnaeus – Botanist and Naturalist Developed the current 7 category naming system we use today. Did not agree with Darwin’s Theory of Evolution through natural
Descent, but understood that similar organisms shared similar traits. Binomial Nomenclature:
two word naming system, the Genus and species○ Genus – capitalized, ○ species – never capitalized
Abbreviated to – G. spp. Always typed in italics Underlined when written
Genus species
○ Homo sapien – modern humans H. sapien
Linnaeus’s System (7 categories) Kingdom Phylum Class Order Family Genus Species
Broad characteristics (unique & grouped)
to
Narrow characteristics (Specific & individual)
Kingdom
Phylum
class
order FFamily G
Genus Sspecies
KPh
CO
Grizzly bear Black bear Giant panda Red fox Abert squirrel
Coral snake Sea star
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos
Ursus arctos
Ursus maritimus
When written or typed the genus is always capitalized and the species is not
Evolutionary Classification Phylogeny- study of evolutionary
relationships among organisms
Biologists classify organisms by
grouping them according to evolutionary descent, not physical characteristics.
Cladograms Uses derived characteristics to show
evolutionary relationships among a group of organisms
Molecular Clock
CLASSIFICATION BASED ON VISIBLE SIMILARITIES
CLADOGRAM
AppendagesConical Shells
Crab Barnacle Limpet Crab Barnacle Limpet
Crustaceans Gastropod
Molted exoskeleton
Segmentation
Tiny free-swimming larva
Kingdoms and Domains
All Living Organisms
Eukaryotes
Eukarya
Protista Fungi Plantae Animalia
Prokaryotes
Bacteria
Eubacteria
Archaea
Archaebacteria
Kingdoms and Domains pg 459
DOMAIN
KINGDOM
CELL TYPE
CELL STRUCTURES
NUMBER OF CELLS
MODE OF NUTRITION
EXAMPLES
Bacteria
Eubacteria
Prokaryote
Cell walls with peptidoglycan
Unicellular
Autotroph or heterotroph
Streptococcus, Escherichia coli
Archaea
Archaebacteria
Prokaryote
Cell walls without peptidoglycan
Unicellular
Autotroph or heterotroph
Methanogens, halophiles
Protista
Eukaryote
Cell walls of cellulose in some; some have chloroplasts
Most unicellular; some colonial; some multicellular
Autotroph or heterotroph
Amoeba, Paramecium, slime molds, giant kelp
Fungi
Eukaryote
Cell walls of chitin
Most multicellular; some unicellular
Heterotroph
Mushrooms, yeasts
Plantae
Eukaryote
Cell walls of cellulose; chloroplasts
Multicellular
Autotroph
Mosses, ferns, flowering plants
Animalia
Eukaryote
No cell walls or chloroplasts
Multicellular
Heterotroph
Sponges, worms, insects, fishes, mammals
Eukarya
Classification of Living Things
DOMAIN BACTERIA
DOMAIN ARCHAEA
DOMAIN EUKARYA
Eubacteria
Archaebacteria
Protista
Plantae
Fungi
Animalia
Kingdoms
Identify through Dichotomous Key Used to identify organisms based on
physical characteristics. A series of paired statements are used
to separate characteristics of different organisms.
From the simple: To the complex:
Texas Wildlife – Turtles
Texas Plants – NRCS
Interactive
Identify through images:
Endosymbiotic Theory