Download 1. Classification Notes

I.
Classifying Organisms
A. Why do Scientists Classify?
1. Biologists use classification to organize living things
into groups so that organisms are easier to study.
2. Classification is the process of grouping things
based on their similarities.
a. The scientific study of how living things are
classified is called taxonomy.
B. Early Classification System
1. Aristotle’s System- he classified organism
by the way they moved.
C. The Classification System of Linnaeus
1. He placed organisms in groups based on their
observable features.
2. Linnaeus also used his observations to devise a
naming system for organisms.
3. In Linnaeus’s naming system, called binomial
nomenclature.
a. Two part name
i. Genus ii. Species 4. Why two part name?
D. Classification Today
1. Species with similar evolutionary histories are
classified more closely together.
E. Levels of Classification
1. Seven Levels or Taxons.
2. Kingdom, Phylum, Class, Order, Family, Genus
and Species.
F. Using Classification System
1. A taxonomic key is a series of paired statements
that describe the physical characteristics of
different organisms.