Classification of Organisms Students should be able to: * Understand why a classification system is important * Understand that there are a variety of ways to classify organisms organisms * Understand the origins of our modern classification system Developed by: Andrew Leech

What is an Organism? Organism: any living thing. This includes everything from single celled This includes everything from single celled bacteria, all the way to the redwood tree or Blue Whale.

You will see 14 different organisms, each of them labeled with a letter. In your groups, write down two main classification groups (color, body plan, behavior, habitat). Then place the corresponding letters under the correct classification. The Classification Game!! Get into Pairs

For Example These organisms have been classified by their color. Red Green

ARE YOU READY!

One Possible Solution Plants Animals ????

Did You Have Problems?? There are several different ways to classify these Organisms (color, shape, size, number of legs). How many groups had one or two that did not fit into either of your two classifications? What should you do when this happens?

Development of Classification? Aristotle (350 B.C.) grouped organisms: 1.body parts 2.life histories 3.Activities 4.character.

10 groups of animals: 6 - “blooded”, 4 “bloodless”. Blooded: Humans, birds and fish Bloodless: insects and mollusks Development of Classification?

As organisms were discovered, scientists had As organisms were discovered, scientists had to add to Aristotle’s original groupings. Increasingly confusing and difficult to use Increasingly confusing and difficult to use Lack of universal system Lack of universal system

Modern Classification Plants and Animals. Plants and Animals. Discovered organisms that did not fit (Fungi) Discovered organisms that did not fit (Fungi) Origins of Classification

Modern Classification Invention of the microscope – discovered Invention of the microscope – discovered organisms showing characteristics of both plants and animals (Protists) Improvements of the microscope led to 2 Improvements of the microscope led to 2 bacterial kingdoms (eubacteria & archaebacteria) Origins of Classification

n TAXONOMY (Systematics) –organisms grouped by shared characteristics DERIVED CHARACTERISTICS. –Scientists were then able to find the common ancestry of the organisms.

Different ways of grouping n PHENETIC SYSTEM –PHENOTYPIC similarities (physical) n (Dolphins have body plan similar to sharks) n BEHAVIORAL – Dolphins share habitat, feeding patterns, movement with sharks

Different ways of grouping n GENOTYPIC SYSTEM –Grouped according to similarities in DNA

Cladistics n CLADISTIC SYSTEM. –Phylogeny – evolutionary history –Ex. So birds might be related to reptiles, because scientists think that birds evolved from early dinosaurs.

Scientific Names n BINOMIAL NOMENCLATURE –GENUS and SPECIES of the organism. –1 st word - Genus, 2 nd word - Species. –A binomial - two words

Who do I have to thank for this? n Swedish botanist Carolus Linnaeus (1753) n Hierarchical system –species was the smallest unit, and that each species (or taxon) belonged to a higher category.

Carlous Linneus

KingdomPhylumClassOrderFamilyGenusSpecies What Kingdom are you in? What phylum are you in? Why?

The Human Species Kingdom:Phylum:Class:Order:Family:Genus:Species: Animalia (Animal in Latin) Chordata (Spinal Cord) Mammalia (have mammary glands) Primates (two mammary glands) Hominoidea (bipedalism) Homo Sapien

When you refer to an organism scientifically, you always use the genus and the specie names. Therefore, the human species would be referred to as: Homo sapien

Conclusion The classification system for organisms have been around for a long time. It has endured several changes and is quite complex. Without it modern biology could not exist, much in the same way that a grocery store would go out of business if it did not have a classification system.