Diversity in BiologyOrganising Diversity

Two Main Classification SystemsSix Kingdom System

More traditional, widely usedClassifies organisms into taxa (groups)Classification based on

Morphological and physiological similarities Does not consider evolutionary relationships

Six Kingdom SystemGroups all living

organisms into six groups:ArchaebacteriaEubacteria

All bacteria used to be in one kingdom called Monera

ProtistaFungiPlantaeAnimalia

Two Main Classification SystemsThree Domain System

More recent, not as widely usedClassification based on

Phylogeny evolutionary history of groups of organisms differences in the sequences in the cell's ribosomal

RNAs (rRNA) cell's membrane lipid structure sensitivity to antibiotics.

3 Domain System

Three-domain SystemBetter reflects evolutionary history of life

3 Domains of LifeArchaebacteria

are prokaryotes lack peptidoglycan in cell walls

Eubacteria (true bacteria) are prokaryotes (no nuclei)

Eukaryotes Protists, fungi, plants, animals

A hybrid systemBlend of both

Systems3 domains, with 4

kingdoms within Eukarya

Used in both systematics and Taxonomy.

The Six Kingdoms and Domains number of Cells energy cell type examples

archaebacteria unicellular

some autotrophic, most chemotrophic

prokaryote "extremophiles"

eubacteria unicellular autotrophic and heterotrophic prokaryote bacteria, E. coli

fungae most multicellular heterotrophic eukaryote mushrooms,

yeast

plantae multicellular autotrophic eukaryote trees, grass

animalia multicellular heterotrophic eukaryote humans, insects, worms

protista most unicellular heterotrophic or autotrophic eukaryote

ameba, paramecium, algae

What kind of organism is it…Sea MonkeyFireflyRingwormJellyfishSpider monkeyCrayfishSea Horse

Photo Credit: Audringje; flickr

Panthera pardus

Binomial NomenclatureScientific names must either be underlined or

italicizedThe genus is always capitalized, the species

is lowercaseCan be abbreviated. Ex. P. leo and P. tigris

What are the scientific names of each of these organisms?

Kingdom Animalia Animalia AnimaliaPhylum Chordata Chordata ChordataClass Mammalia Mammalia AvesOrder Carnivora Carnivora AnseriformesFamily Felidae Felidae AnatidaeGenus Panthera Panthera Anas

Species Leo Tigris acouta

What is a species?

Defined as organisms that can interbreed with one another, and produce fertile offspring

When two organisms of different species interbreed, the offspring is called a HYBRIDThese offspring are usually infertile, therefore do not form a new species.

Example:  ligers and mules

SystematicsDichotomous Keys

Used to identify organismsAt each stage, there are only 2 choices!

1. Has green coloured body ......go to 2

Has purple coloured body ..... go to 4

2. Has 4 legs .....go to 3

Has 8 legs .......... Deerus octagis3. Has a tail ........ Deerus pestis

Does not have a tail ..... Deerus magnus4. Has a pointy hump ...... Deerus humpis

Does not have a pointy hump.....go to 5

5. Has ears .........Deerus purplinis  Does not have ears ......Deerus deafus

Deerus magnus

Deerus pestis Deerus octagis

Deerus puplinis

Deerus deafus Deerus humpus

Body Colour

GREEN

4 Legs

TailDeerus pestis

No TailDeerus magnus

8 LegsDeerus octagus

PURPLE

Pointy HumpDeerus humpis

No Pointy Hump

Has earsDeerus purplinis

No EarsDeerus deafus

Dichotomous Key