Taxonomy and phylogeny• Taxonomy the study of classification - how organisms are

placed in groups or taxa (singular = taxon)

• Phylogeny the study of the evolutionary history of living

organisms

• Classification now uses phylogeny when arranging organisms into groups so classification reflects evolutionary relationships

• It shows that closely related species share a common ancestor (which may now be extinct)

• A range of characteristics are used e.g. anatomy, behaviour, embryological development, molecular structure (proteins and DNA)

The evolutionary relationships of the wolf, dog and fox

Classification of the plant kingdom based on phylogeny

Anatomy and embryology This is evidence for a common ancestor for these

mammals

Classification of reptiles and birds based on phylogeny

Classification of leopard, skunk, otter, dog and wolf based on phylogeny

Are chimps in the same genus as humans?

See page 212 – 213 textbook

Using DNA bases as evidence which 2 animals are most closely related?

And which are most distantly related?

Animals % difference in bases C, G, A and T in coding DNA

human / chimpanzee 0.87

human / gorilla 1.04

human / orang-utan 2.18

chimpanzee / gorilla 0.99

chimpanzee / orang-utan

2.14

gorilla / orang-utan 2.25

Classification of humans and apes based on phylogeny

Classification – the binomial system – Carolus Linnaeus,

18C

What does Binomial mean?

• Each name has 2 parts.• The first is a group of similar species,

the genus.• The second is the single species.• The genus always has a capital

letter and the species never has.• The name is typed in italics, or

underlined when hand written.

Some examples – common names?

• Homo sapiens• Vibrio cholerae• Canis lupus• Mycobacterium tuberculosis

So what is a species?

• Members of the same species show similar morphological, biochemical (e.g. DNA) and physiological characteristics and……

can breed together, producing fertile offspring.

List the 7 levels of the hierarchy of taxa (classification

groups)• There are 5 kingdoms, the largest

groups.

• Kingdom, Phylum, Class, Order, Family, Genus, Species.

• King Philip could only find gruesome socks!

The subdivisions of a kingdom http://advancedsciences.cambridge.org/ocr/biology_1/animation/3392

how can you learn the names?

Here are 2 examples each from a different kingdom.

• Animalia Plantae• Chordata Angiospermophyta• Mammalia Dicotyledonae• Primata Rosales• Hominidae Papilionaceae• Homo Lathyrus• sapiens ordoratus (human) (sweet pea)

Classifying the grizzly bear

Each organism is given 2 names – a binomial = genus + species e.g. Ursus horribilis

Checking your understanding

1) Complete the questions in your Classification workbooklet.

2) answer SAQ 1 page 209

3) what is the binomial system of naming organisms? and why is important in Biology?

http://advancedsciences.cambridge.org/ocr/biology_1/animation/3392

5 kingdoms (1988)http://advancedsciences.cambridge.org/ocr/biology_1/animation/5278

Prokaryote(Monera), Protoctista, Fungi, Plantae, Animalia

Kingdom ?

• Hyphae have _________ cell walls.• Hyphae secrete ________ and absorb

small _______ molecules.• Hetero__________.

Kingdom ?

• Multicellular, Pho_____________, auto__________.

• _____________ cell walls.• Non - ___________.

Kingdom ?

• Multi__________, Non – ph________, hetero___________ with _________ coordination.

Kingdom Pro______?

• Eu___________.• Uni - __________ or assemblages of

similar _____.• Some _________ and some

_____________.

Kingdom Pro_______?

• No membrane - _________ ________.• N________ (no histone protein) ,

c_________ DNA.• Peptidoglycan _____ ______.