chapter 18 classification organization and naming systems based on morphology and genetics humans...
TRANSCRIPT
Chapter 18
Classification
Organization and naming systems based on morphology and genetics
Humans have a tendency to see commonalities and differences,
clustering images by appearance.
Aristotelian classification
Life
Plant Animal
Herb Shrub Tree Aristotle grouped organisms based on appearance and abilities.
Why Classify?
• To study the diversity of life, biologists use a classification system to name organisms and group them in a logical manner.
• To avoid the confusion caused by regional common names.
Texas bluebonnet (Lupinus texensis )
Taxonomy
– the science of classification– Uses Latin…descriptive, universal,
“dead” language that never changes– Uses binomial nomenclature
• Two word naming system of Genus & species = scientific name
– Uses hierarchy of categories from general to specific
Common names
• Many people refer to organisms by common names rather than scientific names.
• Be careful that common names do not always reflect the biology of the organism.
• Example: starfish are not “fish”
Comparing related animals
• Lynx rufus, lynx
• Panthera concolor, mountain lion
• Lynx canadensis, bobcat• Which two are more related?
How do you know?
Mountain lion
BobcatLynx
Dichotomous key: system to identify organisms and their
scientific names
• A key is made up of sets of numbered statements.
• Each set deals with a single characteristic of an organism, such as leaf shape or arrangement.
Carolus Linnaeus (1707-1778)
• Created a classification system with seven hierarchical levels
• Kingdom• Phylum• Class• Order • Family• Genus• species
Human classification:Kingdom Animalia
PhylumChordata
ClassMammalia
OrderPrimates
FamilyHominidae
GenusHomo
speciessapiens
Grizzly bear Black bearGiant panda Red fox Abert
squirrelCoral snake Sea starKINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos
Classification of Human and Chimp
Level Human Chimp
Kingdom Animalia Animalia
Phylum Chordata Chordata
Class Mamalia Mamalia
Order Primate Primate
Family Hominidae Pongidae
Genus Homo Pan
species sapien troglodytes
Kingdom…Phylum…Class…Order…Family…Genus species…(variety) or (breed)
Phylogeny
• Studying the evolutionary history and relationships of organisms
Cladograms• Making a Family Tree
• Represent evolutionary relationships, phylogeny, and not just physical appearances
Cladograms• Cladistics: a phylogenic study that
assumes how groups of organisms diverged and evolved
Theropods
Allosaurus
Sinornis
Velociraptor
Archaeopteryx
Light bones3-toed foot;
wishboneDown
feathersFeathers withshaft, veins,and barbs
Flight feathers;arms as long
as legs
Traditional classification vs. Cladograms
CLASSIFICATION BASED ON VISIBLE
SIMILARITIES
CLADOGRAM BASED ON DERIVED
CHARACTERS
Appendages Conical Shells
Crab Barnacle Limpet Crab Barnacle Limpet
Crustaceans Gastropod
Molted exoskeleton
Segmentation
Tiny free-swimming larva
Current six-kingdom classification
• Archaebacteria: prokaryotic
• Eubacteria: prokaryotic
• Protists: eukaryotic
• Fungi: eukaryotic
• Plants: eukaryotic
• Animals: eukaryotic
Modern classification systems include the three-domain system which includes the 6 kingdom system.
• Just a few years ago, all bacteria and some protists were labeled Monera.
Kingdoms
Eubacteria
Archaebacteria
Protista
Plantae
Fungi
Animalia
DOMAIN EUKARYA
DOMAIN ARCHAEA
DOMAIN BACTERIA
Three Domain System
Key Characteristics of Domains and Kingdoms
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
Six Kingdom
classification
Prokaryotic or
eukaryotic
Unicellular or
multicellular
Autotroph or
heterotroph
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Pro Uni both
Pro Uni both
Eu most uni both
Eu most multi hetero
Eu multi auto
Eu multi hetero
Archaebacteria overview• prokaryotic• Most live in extreme
environments such as swamps, deep-ocean hydrothermal vents, and seawater evaporating ponds.
• Most do not use oxygen to respire.
• Examples: Thermophiles, Halophiles, Methanogens
Eubacteria overview• prokaryotic• very strong cell walls• a less complex
genetic makeup than found in archaebacteria or eukaryotes
• diverse habitat• Examples: Strep,
Lacto-bacillus, E. coli
Protist overview• diverse species that share
some characteristics.
• eukaryote
• lacks complex organ systems
• lives in moist environments• diverse metabolism
Protozoans: animal-like protists• Heterotroph: consume organic matter
• Unicellular
• Examples: Amoeba, paramecia
Algae: plant-like protists• Autotroph: uses light to make sugars
through photosynthesis
• Lack roots, stems, and leaves
• Examples: algae, kelp, sea-weed
Fungus-like protists• Decompose dead matter• Motility during some stage of life cycle• No chitin in cell walls
• Examples: Slime-mold, powdery mildew
Fungi overview
• Eukaryotic• Decomposes matter by
absorbing materials• Multicellular or unicellular• Examples: bread mold,
mushrooms, athletes foot, ring worm
Plant overview• Eukaryotic• Multicellular• Photosynthetic:
produce oxygen • Immobile, sessile• Cell walls• Examples: fruit, ferns,
mosses, trees, grasses
Animal overview• Eukaryotic• Multicellular• Mostly mobile• Lack cell walls• Diverse habitats• Examples: lions, tigers & bears,
oh my!
Bacteria
Protista
AnimaliaPlantae Fungi
EuPro
MultiUni
(Seaweeds)
Nutritional types
Auto(photo) Hetero(absorb) Hetero(ingest)
Evolution and the 6 Kingdoms
Six Kingdom
classification
Prokaryotic or
eukaryotic
Unicellular or
multicellular
Autotroph or
heterotroph
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Pro Uni both
Pro Uni both
Eu most uni both
Eu most multi hetero
Eu multi auto
Eu multi hetero
Classification systems video
Click on image to play video.
Panthera leo? (1)
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Panthera leo? (2)
Click on image to play video.