QUIZ 1. What is the science that describes, names

and classifies organisms?

2. Linnaeus classified organisms according to their ______ & ______.

3. (True or False) Binomial nomenclature gives the phylum and genus names.

4. What is the species name for humans?

TaxonomyThe science of organizing life

• Taxon (taxa plural) - groups within a taxonomic system

Linnaean System

Group organisms into levels according to their visible form & structure

ACTIVITY 1 Classify Objects by Characteristics

Spider Key

KingdomPhylum

ClassOrderFamilyGenusspecies

King Phillip

Came Over For

Ginger Snaps

Linnaean System

Developed a 2 - part naming system called

Binomial Nomenclature

Genus name followed by species identifier

• Written in italics Genus name capitalized

• Latin roots & descriptive name

example: Homo sapiens

•Subspecies (variations of a species living in different areas) name follows species identifier

SystematicsDescribing, classifying and naming organisms in

terms of their natural relationships

Natural relationships = physical features, embryos, genes in the nucleus, DNA & RNA

Biologist can choose & combine systems of classification but the classification should reflect Phylogeny

What is Phylogeny?

Hypothesis of the evolutionary history of species or taxonomic group

Phylogenetics – the evolutionary relationships among organisms;

• Compare visible similarities among current living or fossils or compare chromosomes and macromolecules

• Represent hypotheses in the form of phylogenetic diagram also called phylogenetic tree

Activity 2

• Create a Phylogenetic tree

• Family tree

you – parents- grand parents- great grandparent & so on.

What natural relationships does your tree represent?

Systematics• Compares homologous features items that

share a common ancestry • Important to separate from analogous

features similar because they have similar function

The greater the number of homologous features shared by two organisms the

closer they are related

Homologous vs. Analogous

CLADISTICS A phylogenetic classification system that uses

shared derived characters & ancestry as the only criteria for grouping taxa

• Shared character – feature that all members of a group have in common

• Derived character – feature that evolved only within the group under consideration

CLADISTICS• Clad – group of organisms that include an

ancestor plus all of its descendants

• Cladograms – phylogenetic diagrams

CLADOGRAMS

Cladogram Group

ANY QUESTIONS?

HOMEWORK• READ p 341 – 345

• Answers Question 1- 6 on Page 345