1. CLASSIFICATION
“Grouping together items into categories based on a set criteria”

2. Group Activity get yourselves into groups of 4
Brainstorm and list 20 domesticated animals
-your job is to group your list of animals into different categories
-you MUST:
-use more than three categories
-be prepared to describe the criteria you used for your groupings

3. Biological Classifcation
“Systematic grouping of organisms into categories on the basis of defined criteria”
Taxonomy
“the science of classifying ALL organisms”

4. Taxonomy Very general millions of species? - how to start classifying?
behaviour
where they live/habitat
appearance and characteristics
(MORPHOLOGY)
Mosquitoes –50 species
Seed plants – species

5. Challenges to Classification?
- Yesterday?
Variation:
over space and time
among individuals
Evolution
DNA

6. History of Classification
The biggest classification problem has always been consistency
History of Classification
(Coles notes)
Ancient Greece
First to introduce classification and binomial definition
classify ALL LIVING things (Historia Animalium)
blood/no blood, water/land
-Hierarchical; each organism fixed position
Humans
Animals
Plants
Great Chain of Being
Issues?
complex plants below simple animals
little genetic relationship
Evolution?
Aristotle
(384 – 322 BC)

7. Carl Linnaeus (1707 - 1778) Irregularity amongst names
Virtually no innovation to Aristotle’s work till the 16th century
virtually 2000 years!!!
-shamans/Aboriginal healers/Andrea Cesalpino
Irregularity amongst names
needed agreed upon set of naming guidelines
Scientific naming
Carl Linnaeus ( )
Cesalpino went against Aristotle’s ideas.
Linnaeus was Swedish naturalist
- the father of taxonomy
- 2 key contributions to classification:
Consistent way of grouping species according to morphological similarities

8. Binomial Nomenclature
Naming system
- 2 parts
1. Genus  species; capitalized, italicized
2. species  specific species; italicized
Gerbera hybrida
Binomial Nomenclature
Flawed –bc of classifications he chose
standard naming system for all organisms
simple
convenient
flawed
Systema Nature (1735)

9. Ursus americanus
Share many characteristics
Ursus maritimus
Share few characteristics
Phascolarctus cinereus

10. Ranks based on shared characteristics
Taxonomic Levels
General/fewer similarities
kingdom
phylum
class
order
family
genus
species
Animalia
Chordata
Mammalia
Primates
Hominidae
Homo
sapiens
Ranks based on shared characteristics
-each level = taxon
Specific/more
- refined into subcategories

11. Dichotomous Keys
“structure in which a large set of items is broken down into smaller subset, ultimately leading to the smallest available classification unit.”
- series of branching two-part statements used to identify organisms
- large set broken down to smallest classification unit
- larger number of species, the more specific questions become
Difficulties?
number of species
distinguishing characteristics are internal
agreeing on criteria
Page 18
Textbook
Dichotomous Key practice

12. Activity Get into groups of 4-6
Within your group you will be creating your own dichotomous key
The subject of your key will be classifying each member of your group
Remember dichotomous keys “are a series of branching two-part statements used to identify organisms.”
Therefore your keys need to contain multiple steps and be specific
When, finished, you must demonstrate the viability of your key to Mr. Faulhafer for assessment
Complete questions 5 and 8 on page 20 of textbook