1. Classification of Living Things
UNIT 16
Articles from digital text:

2. Learning Objectives Living things can be classified based on
structural evidence
embryological evidence
evolutionary evidence
molecular (relatedness of DNA sequence) evidence
Carolus Linnaeus developed the system of taxonomy and binomial nomenclature that is still in use today.

3. Classification
Method of organizing plants and animals into categories based on their appearance and the natural relationships between them
DNA composition is most reliable method for identifying the relationships among organisms
Taxonomy
science of classifying organisms
makes sense of the diversity of life in order to study it better

4. Aristotle
Began arranging organisms according to their physical similarities (previously – useful vs. harmful)
animals: red blood (vertebrates) vs. no red blood
plants: size; herbs, shrubs, trees

5. Benefits of Classification
Helps biologists
keep track of living things
study their differences and similarities
learn how living things are related to one another through evolution (the process by which living things change over generations)
save time and effort

6. Benefits of Classification
Today’s system:
natural system since it represents genuine relationships between organisms
the more closely organisms are related to each other, the more features they have in common
hierarchical – categories are grouped according to size in a series of successively larger ranks

7. Carolus Linnaeus Swedish physician and naturalist (1707-1778)
“Father of taxonomy”
Established 1st orderly system of classifying living things
Introduced binomial nomenclature
His system was able to impose a much-needed order on the study of life 

8. Classification Groups
Taxons (groups) range in order of specificity
General to specific
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species  

9. Classification Examples
Animal Diversity Web