Classification systems help organize living things into logical groups based on shared characteristics. There are 8 main levels of classification - domain, kingdom, phylum, class, order, family, genus, and species. The modern system developed from early classifiers like Aristotle who grouped animals based on traits like blood and reproduction. Carolus Linnaeus established binomial nomenclature using Latin names, with the genus first followed by the specific epithet, to avoid confusion from varying common names between regions. This scientific naming system along with classification helps study relationships between organisms and understand evolution.

1. Classification of Living Things

2. Why do we classify things?
– Supermarket aisles
– Libraries
– Classes
– Teams/sports
– Members of a family
– Roads
– Cities
– Money

3. Why Classify Organisms?
• To represent relationships among
• organisms
• To makes things easier to find, identify,
• and study
• nTo understand our own evolution!

4. What is classification?
• Classification: putting things into orderly groups
based on similar characteristics
• Taxonomy: the science of describing, naming, and
classifying organisms

5. Early classification
• Aristotle grouped everything into
simple groups such as animals or plants
• He then grouped animals according to if they had
blood or didn’t have blood, and if they had live young
or laid eggs, and so on…

6. Binomial Nomenclature/ Scientific name
• Developed by Carolus Linnaeus
• Swedish Biologist 1700’s
• Two-name system
• Genus and species named using
Latin or Greek words
• Father of Taxonomy

7. Why Use a Scientific Name?
• We use scientific names to avoid confusion
• Many common names vary from region to
region and country to country
• Using a single standard Latin name for each
species avoids any chance of confusion

8. Rules used to write scientific names
• An organism’s genus is always written first; the
organism’s species is always written second
• The genus is Capitalized; the species is written in
lower case
• Scientific names of organisms are always italicized
or underlined
• Ex.: Homo sapiens ( Human –common name)
*Homo - genus name ( first name)
* sapiens – species name ( second name )

10. The modern system of classification has 8
levels:
• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

11. Helpful way to remember the 8 levels
• Dumb kids playing catch on freeways get
squashed
• Or…make up your own…
– D K P C O F G S