CH 18.1 Finding Order in Diversity
SC.912.L.15.4: Describe how and why organisms are hierarchically classified and based on
evolutionary relationships.
Binomial nomenclature –each species is assigned a two-part scientific name.
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sUse Latin/Greek names to each species.
Ex. Genus species = Homo sapien or Felis
concolor.
Genus-large group of similar species &
species is unique to each species.
Systemics is the naming & grouping of
organism.
Linnaean Classification System
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100 years before Darwin.
7 hierarchical taxa: Kingdom, Phylum, Class,
Order, Family, Genus, species.
How to remember? King Phillip Came Over
For Grape Soda
Closely related divisions are grouped into the next rank (p.514).
CH 18.2 Modern Evolutionary Classifications
SC.912.L.15.5: Explain the reasons for changes in how organisms are classified.
Phylogeny-goal is to group species into
larger categories that reflect lines of
evolutionary descent, rather than overall
similarities & differences.
Clade-group of species that includes a
common ancestor & all descendents of
that ancestor.
Cladogram-diagram to link clades(p.519).
Each node represents the last point at
which a species in lineages above the
node shared a common ancestor.
Bottom of cladogram represents the common ancestor shared by all organisms in the diagram.
Organisms are assigned to clades based on derived characteristics (traits that arose in the most
common ancestor & passed to its descendents). See p.519
CH 18.3 Building the Tree of Life
SC.912.L.15.6: Discuss distinguishing characteristics of the domains and kingdoms of living
organisms. AA/MC
Six Kingdoms: Plants, Animals, Protists, Fungi, Archaeabacteria, Eubacteria
3 Domains: Bacteria, Archaea, Eukarya
Tree of Life- current hypotheses regarding evolutionary relationships among the taxa within the 3
domains of life.