Taxonomy (Classification) and Phylogeny (Cladistics) · Domain Kingdom Phylum Class Order Family...

Taxonomy (Classification) and Phylogeny (Cladistics)

• Classification is the grouping of objects based on physical similarities. In biology when doing this with organisms, it is called taxonomy.

• It is predominately based on morphology.• Linnaeus and Whittaker gave us this

system• Classifies diverse organisms into “like

groups” based on traits. As the traits become more specific, fewer and fewer organisms are together.

8 Levels of taxonomy….self check!

DomainKingdomPhylumClassOrderFamilyGenusSpecies

Let’s look at the 8 Levels of taxonomy one more time!

DomainKingdomPhylumClassOrderFamilyGenusSpecies

The Three Domains

• Domain Archaea– Ancient prokaryotes

• Domain Bacteria– Modern prokaryotes

• Domain Eukarya- all eukaryotic cells– plantae, animalia, fungi, protista

Before we move on…protista???

The domain eukarya is very diverse …WHY???

• Taxonomists give a unique scientific name to each species they know about whether it’s alive today or extinct. (not to be confused with taxidermist)

• The scientific name comes from one of two “dead” languages – Latin or ancient Greek.

• Why use a dead language?

Devil Cat

Ghost Cat

Mountain Lion

Screaming Cat

Puma

Florida Panther

Cougar

• There are at least 50 common names for the animal shown on the previous 7 slides.

• Common names vary according to region.

• Soooo……that’s why we use a scientific name, based on Latin!

Binomial Nomenclature• a two part naming system for writing scientific

names.• The genus name is written first (always Capitalized)• The species name is written second (never

capitalized).• Both words are

– italicized if typed or underlined if hand written.FELIS CONCOLOR

– Felis concolor or F. concolor– Apply: Which is the genus? The species?

• Cladistics /Phylogeny- is a relatively new system of classification that uses shared derived traits to establish evolutionary relationships.

• A derived trait is a feature that evolved only within the group under consideration.

• A phylogenetic tree based on a cladisticanalysis is called a cladogram.

• Out-group is the least related group, will be found on the far left of our diagrams!

• Synapomorphies = derived characteristics• Clade = A group of organisms and their

common ancestor.

Think – Pair - Share

• What is a shared derived trait that humans have?

• Talk with the person next to you, come up with a couple of ideas.

• Be ready to share!

Who is the most derived? Who is the out-group? What is a shared derived trait for pigeons?What is a shared derived trait for mammals?Where would you put monkeys?