1. Classification and Taxonomy

2. Why Classify???
Scientists classify organisms in order to organise the great diversity of organisms into manageable groups to aid study
Classification systems have two features:
A universally accepted name for each organism (so all scientists all over the world know they are talking about the same thing)
A placement of organisms into groups that have a real biological meaning
Organisms in the same group share important traits or characteristics.

3. The System of Carolus Linnaeus
Developed by Carolus Linnaeus, a Swedish botanist
It is called: binomial nomenclature
Details:
Gives each organism a two part name
The first part tells the genus of the organism
The second part tells the species – often a Latin description of some important characteristic

4. Example of Binomial nomenclature
Acer palmatum
Acer rubrum
Acer- maple
Palmatum – latin for hand
Acer – the genus name for all maples
Rubrum : latin word for red

5. Notation: Capitalize the genus name, but not the species
The name must be written in italics
Orcinus orca
Haliaeetus leucocephalus

6. The Classification System of Linnaeus
After naming organisms he grouped them according to shared body features.
Organisms that shared important characteristics were classified as the same group.
Taxa = groups
Taxonomy = the science of naming organisms and assigning them into species

7. Details:
The smallest taxon is species: a group of organisms that share similar characteristics and that can breed with one another
If two species share many features, but are clearly separate biological units, they classified as different species within the same genus
eg. Felis domesticus
Eg. Felis concolor

8. Family A family is a larger taxon than a genus
For example the genera Felis and Panthera belong to Felidae (cats)
Felidae Panthera tigris Felidae Felis lynx

9. Order The next larger taxon is called Order
For example cats (felidae) and dogs (Canidae) belong to Carnivora (meat eater)

10. Class, Phyla, Kingdom Orders are grouped into Classes (Mammalia)
Classes are grouped into Phyla (Chordata)
Phyla are grouped into Kingdom (Animalia)
Kingdom
Phylla (Phylum)
Class
Order
Family
Genus
Species
(King Phillip Cuts Open Five Green Snakes)

11. Create a dichotomous key based on the following emojis
Split into 2 categories…

12. Use the dichotomous key to identify the following birds
Bird W – Geospiza
Bird X – Platyspiza
Bird Y – Certhidea
Bird Z – Camarhynchus

13. Dichotomous key can also be made like this…

14. Dichotomous Key – Shoe Activity
In groups of 5-6 use the whiteboards to create a dichotomous key on the different shoes each group member is wearing. Making sure to have questions listed and ensure each shoe is classified as it’s own “species”

15. Five Kingdom System
Monera
Protista
Fungi
Plantae
Animalia

16. Five Kingdoms

17. Monera All monerans are prokaryotes Characteristics: Escherichia coli
Lack nuclei
Lack mitochondria
Lack chloroplasts
Reproduce by binary fission
Escherichia coli

18. Protista All protists are single celled eukaryotic organisms
Characteristics:
Has nucleus
Have organelles – which can include chloroplasts
Kingdom Protista is divided into three groups
Animal-like
Plant-like
Fungi-like

19. Giardia Diatoms Slime mold Animal – like
(unicellullar, find food from the environment, move to find food source)
Plant – like
(unicellular, make their own food (photosynthetic)
Fungi – like
(find food from the environment, reproduce my producing spores, have cell walls)

20. Fungi Have cell walls but don’t contain cellulose
Fungi are heterotrophs who do not carry out photosynthesis.
Do not carry out photosynthesis
Have many nuclei but not in separate cells

21. Plantae All plants: Are Multicellular
Have cell walls containing cellulose
Autotrophic: Able to carry out photosynthesis using chlorophyll

22. Animalia All animals are: Multicellular
Heterotrophic (can not make its own food and obtains energy from food it eats)
Lack cell walls

23. Taxonomy Today Why things have changed?
Only the taxon species has a clear biological identity
Members share a common gene pool because they interbreed
The organisms themselves decide who belongs and who doesn’t to their species
All other taxa are “constructed” by biologists
They try to use biologically important characteristics, but… different biologists have different opinions
Some species have been moved into different taxa (and others will be in the future)

24. Taxonomy and Evolutionary Relationships
Evolutionary theory states: that living species have evolved from earlier species.
Thus, taxonomists group organisms in ways that show evolutionary relationships.
By identifying and studying homologous structures in:
Adult organisms
Developing embryos and in
Well preserved fossils.

25. Species with homologous structures are classified together.
Species with analogous structures are put in different groups.

26. Biochemical Taxonomy
Taxonomists use molecular similarities to classify organisms
Biochemical similarities
All organisms (except some viruses) use DNA to carry genetic information
Organisms may be different but their genes and the proteins that they make are very similar
The sequence of the cytochrome c protein (used in the electron transport chain) is carried by all organisms, but differs slightly between species
These differences have been caused by mutations that occur after the ancestors of the living species diverged
To help us classify organisms into groups, taxonomists can compare:
Nucleotide sequences in DNA and RNA
Amino acid sequences of proteins