a. Classification of organisms into groups based on characteristics & evolutionary history
Modern classification system – Linnaean system
Kingdom – physical characteristics
Phylum (& sub-phylums): Chordate – basic body design
Class: Mammal – general traits (number of limbs)
Order: Primates – specific information
Family: Hominids
Genus: Homo
species: sapien
b. Why classify
- infer evolutionary relationships
- predict characteristics of newly discovered species
- useful to look at families species when assessing extinction in ecosystem
Tentative nature: not fixed – can change as new information available
c. 3 Domains – each with distinctive ribosomalRNA pattern (prokaryote kingdom can be divided into 2)
Archaea: extremophile prokaryotes
(Eu)Bacteria: true bacteria
Eukary(ot)a: eukaryotes
d. Kingdoms
Prokaryotae Fungi
unicellular heterotrophs – saprotrophs
peptidoglycan cell wall chitin cell wall
no true nucleus & membrane-bound organelles reproduce via spores
most have hyphae – network of filaments
Protoctista Plantae Animalia
mostly unicellular multicellular multicellular
no tissue differentiation autotrophs – photosynthetic heterotrophs
reproduce via spores/seeds nervous coordination
cellulose cell wall
e. Assessing relatedness
physical features
Homologous features: evolved from same structure (common ancestor) for different functions
pentadactyl limb divergent evolution
Analogous features: structures evolved independently for same function
insect/bird wing convergent evolution
biochemical methods – reduce problem of morphological convergence
percentage of DNA or proteins shared between organisms / less differences = estimates relatedness
genetic fingerprinting – compare banding patterns
enzyme studies = protein amino acid sequence
Phylogenetic Tree: shows relatedness – shows when most recent common ancestor was
f. Species: group of similar organisms – can interbreed = fertile offspring
g. binomial naming system – universal
Genus name + species name
Starts with CAPITAL lower case
Modern classification system – Linnaean system
Kingdom – physical characteristics
Phylum (& sub-phylums): Chordate – basic body design
Class: Mammal – general traits (number of limbs)
Order: Primates – specific information
Family: Hominids
Genus: Homo
species: sapien
b. Why classify
- infer evolutionary relationships
- predict characteristics of newly discovered species
- useful to look at families species when assessing extinction in ecosystem
Tentative nature: not fixed – can change as new information available
c. 3 Domains – each with distinctive ribosomalRNA pattern (prokaryote kingdom can be divided into 2)
Archaea: extremophile prokaryotes
(Eu)Bacteria: true bacteria
Eukary(ot)a: eukaryotes
d. Kingdoms
Prokaryotae Fungi
unicellular heterotrophs – saprotrophs
peptidoglycan cell wall chitin cell wall
no true nucleus & membrane-bound organelles reproduce via spores
most have hyphae – network of filaments
Protoctista Plantae Animalia
mostly unicellular multicellular multicellular
no tissue differentiation autotrophs – photosynthetic heterotrophs
reproduce via spores/seeds nervous coordination
cellulose cell wall
e. Assessing relatedness
physical features
Homologous features: evolved from same structure (common ancestor) for different functions
pentadactyl limb divergent evolution
Analogous features: structures evolved independently for same function
insect/bird wing convergent evolution
biochemical methods – reduce problem of morphological convergence
percentage of DNA or proteins shared between organisms / less differences = estimates relatedness
genetic fingerprinting – compare banding patterns
enzyme studies = protein amino acid sequence
Phylogenetic Tree: shows relatedness – shows when most recent common ancestor was
f. Species: group of similar organisms – can interbreed = fertile offspring
g. binomial naming system – universal
Genus name + species name
Starts with CAPITAL lower case
