42 Classification Today

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4-2 Classification Today
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4-2 Classification Today

• The Linnaeus classification system (not his
  naming system) has been tweaked for two reasons
• Charles Darwins Theory of Evolution
• and
• Advances in technology

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Evolution and Classification

• During the long history of life on Earth,
  organisms have changed, evolved
• Evolution New kinds of organisms develop from
  previous existing kinds of organisms.
• Taxonomists job is try to classify living things
  so that their groups contain organisms that have
  evolved from the same ancestors.

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FOSSIL RECORD
We can trace some changes over time through the
fossil record.

• Evolutionary history _____________

PHYLOGENY
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Technology and Classification

• Scientists look at
• Large internal and external structures
• Structures with in the cell by using compound
  and electronic microscopes
• Early stages of life development by using cat
  scans and MRIs
• Chemical building blocks using flame and
  spectrophotometers

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2. MORPHOLOGY
Shape and Function
  Image from http//www.angelfire.com/ab7/evo
lution12/evolutionclues.html
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4. CHROMOSOMES
Similar karyotypes suggest closer relationships.
Human http//www.nationmaster.com/wikimir/images/
upload.wikimedia.org/wikipedia/en/thumb/1/18/300px
-Human_karyogram.png Chimpanzee Middle School
Life Science , published by Kendall/Hunt.
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3. EMBRYOLOGY
Animals whose embryos develop in a similar
pattern may be related
Image from http//calspace.ucsd.edu/virtualmuseu
m/litu/03_3.shtml
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Classification groups

• Does two jobs
• 1. Gives every organism a specific scientific
  name
• 2. Groups organisms based on evolutionary
  relationships

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All living things are classified into 7 levels of
organization

• within
  the grouping Similarity of organisms
• Kingdom - largest number not very similar
• Phylum
• Class
• Order
• Family
• Genus
• Species- smallest number very
  similar
  
  Most specific share many characteristics
• Similar in appearance and behavior
  Interbreed to produce offspring

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How to Remember

• In the kingdom we will file the class in order of
  their family genus name and species.
• or
• Kids
• Prefer
• Cheese
• Over
• Fried
• Green
• Spinach

Kingdom Phylum Class Order
Family Genus
Species
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Kingdom Phylum Class Order Family
Genus Species
Animalia
Chordata
Mammalia
Carnivora
Felidae
Panthera
leo
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Based on evolution

• Largest groups represent the earliest ancestors.
  Smallest of the groups contain organisms that
  evolved from shared ancestors that lived in the
  relatively recent past.
• Placements and groupings can change
• Thought of as forming a tree in which the trunk
  is the Kingdom, the main branches are the phyla,
  and the tiny tips of the twigs are the species

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6 KINGDOM SYSTEM

• These relationships can be shown in a diagram
  called a
• _______________________

PHYLOGENETIC TREE
Image from http//sps.k12.ar.us/massengale/im
ages/clip0075.jpg
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Organization