BIODIVERSITY
By: Regina Hernandez
Early System of Classification
 Taxonomy is the branch of
biology that names and groups
organisms according to their
characteristics and evolutionary
history.
 Organisms were first classified
more than 2,000 years ago by
the Greek philosopher Aristotle.
Taxonomy
• Science of biological classification.
• It is concerned with identification,
classification and nomenclature of organisms.
Modern System:Hierarchy
Seven Levels of Organization
 Carolus Linnaeus (mid-1700’)s
was a Swedish biologist who
established a simple system for
classifying and naming
organisms.
 He developed a Hierarchy (a
ranking system) for classifying
organisms that is the Basis for
Modern Taxonomy.
 For this reason, he is considered
to be “father” of modern
taxonomy.
Why Classify?
 Set up an organized
system so scientists can
communicate
 Study similarities and
propose relationships
between organisms
 Show evolutionary
linkages between
organisms
Common Names
 One species can have many different names
• Example:
Mountain lion, puma, cougar, or panther?
•Vary among languages and regions
Keys to Binomial Nomenclature
Felis domesticus
 Must be in Latin
 Must be in italics or underlined
 Genus (1st word) must be capitalized
 Species (2nd word) must be lowercase
Correct or Incorrect?
 Triticum Aestivum - wheat
 Felis domesticus - cat
 canis lupus - wolf
 Canis familiaris - dog
 Populus deltoides - cottonwood
How do scientists classify new
organisms?
 They study their
characteristics.
 They try to see if they are
similar to other already
known organisms.
 They group a new
organism with others that
have similar
characteristics.
What characteristics are important?
 Similarities in DNA and RNA
• Genes show similarities at the
molecular level
• More similar the DNA, the more
recently they shared a common
ancestor
What is the concept of species?
 Do animals with totally different ancestors can
reproduce?
Hierarchy of Classification
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Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
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Dear
King
Philip
Came
Over
For
Good
Soup
DOMAINS
 Eukarya
 Plants, Animals, fungi
or protists
 Archaea
 Organisms in extreme
environments
 Bacteria
 Much more common
than archaea
Inclusive: broad or
general in scope
Inclusive: broad or
general in scope
Exclusive: limited and
restricted; specific
 Let’s play a game!
 PINOY henyo
 Summary
 Why do we need to classify?
 What is the concept of species?
 Mnemonics for hierarchical order.
 Do you think God created us perfectly? Why?
 Assignment
 Read on protection and conservation of species.