the tree of life: what is the point? big question why do we classify organisms?
TRANSCRIPT
The Tree of Life:What is the Point?
Big Question
Why Do We Classify Organisms?
ClassificationA process of grouping
by similarities
Every Day Classification
Organization at
your desk.
The Science of Classification
Scientist who classify ororganize organisms (animals and plants)
are called taxonomists. Taxonomists study
taxonomy.
Taxonomy
• Branch of biology that groups and names organisms
New Discoveries
Questions
How can you answer these questions?
Why is Taxonomy Important?
Unknown species discovered.
New fossil Uncovered.
What is Classification?
Classification arranges objects, ideas, or information
into groups by finding common
traits or characters.
The History of Organization
Aristotle 384-322 BCInterested in biological classification.
Patterns in nature.
Carl Linnaeus1707-1778 ACE
Father ofBiological
Classification!
• 2 Categories –Plants and Animals
• Animals – classified on where they lived– Land, water or air
• Plants – classified on the basis of structure and size – Tree, shrub, herb
• Grouped organisms by similar structure
• Created two-part naming system
• Grouped similar species into same genus
Why Scientists Name Animals
Varecia variegata
• 2 word latin name (by Linneus)
• Uses genus and species name (or descriptive name)
• Italics is used and Genus is capitalized–Quercus alba = white oak
Genus Species Common Name
_______________________________________Canis familaralisCanis lupus
Felis domesticus Felis concolor
Dog Wolf
House Cat
Mountain lion
How Classification Works
Groups are arranged in hierarchical order.
Classification Puzzle
• Brings order to the great diversity of life forms
• Serves as a basis for identifying unfamiliar organisms
• Provides a logical means of naming organisms
• A series of paired statements used to identify organisms
1a. Has fur, go to…………………………2 b. Does not have fur……………………3 2a. Has straight fur………………………4 b. Has curly fur………………………….5 3a. Rough skin……………………………6 b. Smooth skin…………………………..7
Classification of life forms
3 Domains of Life
Bacteria Archaea Eukarya
Includes variousKingdoms:AnimaliaPlantaeFungiProtista
Consist of PROKARYOTES
Domains of Life
7 Classification Groups:
• Kingdom (most inclusive)
• Phylum
• Class
• Order
• Family
• Genus• Species (most specific)
• King
• Phillip
• Came
• Over
• For
• Good
• Spaghetti
ORGANIZATION• KINGDOM Largest• PHYLUM• CLASS• ORDER• FAMILY• GENUS• SPECIES Smallest
Which is the most difficult to assign?
Species:• Most specific• Successful
interbreeding• Fertile
offspring
Donkey + Horse=Mule (infertile)
Cladogram• A diagram showing branching
from a common ancestor• Traits separate each
organisms – derived traits• Assumption – groups of
organisms that diverge from common ancestor retain unique inherited characteristics
Organisms Classified Today Using:
• Structure
• Biochemistry
• Embryology
• Breeding Behavior
• Geographic Distribution
• Homologous parts
• DNA and proteins
• Embryos
• Courtship patterns
• Location (with reference to barriers)
5 Major Kingdoms:
1.Monera
2.Protista
3.Fungi
4.Plantae
5.Animalia
• 1 cell, prokaryotes
• 1/multicell, eukaryotes & algae • Multicelled, decomposers
• Muticelled, autotrophs
• Muticelled heterotrophs
KINGDOM MONERA
• SEPARATED INTO TWO GROUPS– ARCHAEBACTERIA– EUBACTERIA
TRUE BACTERIA ANCIENT BACTERIA
ARCHAEBACTERIA• PROKARYOTIC• UNICELLULAR• HETEROTROPH / AUTOTROPHS
– CHEMOSYNTHETIC – CHEMICALS TO MAKE NRG
• LIVES IN EXTREME ENVIRONMENTS– SWAMPS, HYDROTHERMAL VENTS
• MORE COMPLEX THAN EUBACTERIA• CELL WALL• SEVERAL HUNDRED SPECIES
ARCHAEBACTERIA
VENT BACTERIA SALT-LOVING BACTERIA
EUBACTERIA• “TRUE BACTERIA”
• PROKARYOTIC
• UNICELLULAR
• HETEROTROPH
• STRONG CELL WALLS
• SOME CAUSE DISEASE, BUT MOST HARMLESS
EUBACTERIA
PROTISTA• EUKARYOTES
– NUCLEUS, MEMBRANE BOUND ORGANELLES
• UNICELLULAR, SOME MULTICELLULAR
• HETEROTROPHS & AUTOTROPHS
• MOST VARIED GROUP
• LACK ORGAN SYSTEMS
• MOIST ENVIRONMENTS
PROTISTA
• EUKARYOTIC
• SOME UNICELLULAR, MOST MULTICELLULAR
• HETEROTROPHS– DECOMPOSERS (SAPROPHYTES)
• ABSORB FOOD THROGH CELL WALLS
• 100,000 DIFFERENT SPECIES
• EUKARYOTIC• MULTICELLULAR• AUTOTROPHS • DO NOT MOVE• CELLS ORGANIZED INTO TISSUES,
ORGANS AND SYSTEMS• CELL WALLS – CELLULOSE• 500,000+ SPECIES
• EUKARYOTES
• MULTICELLULAR
• HETEROTROPHS
• NEARLY ALL MOVE
• NO CELL WALLS (MEMBRANE ONLY)
• CELLS ORGANIZED INTO TISSUES, ORGANS, SYSTEMS
Feline Family Members:
Genus: Panthera (Lions &Tigers)
Classification by characteristics:
• Fossil Skulls• DNA
Sequences• Hair Samples • Pictures
Most Useful
Least