Organization rules…

Question: What class is this?

How do you know when to come here?Why do you come to this school?Which block is this?

The answers to these questions are all based on a system of organization that the school follows. Who made these rules? (my personal favorite question!!)

In Biology……..• The activity that involves grouping and naming is called

classification. • The branch of Biology that involves classification of

organisms is called taxonomy!!

Not to be confused with taxidermy!

Classification systems have 2 main purposes:

1. To identify organisms

2. To provide basis for recognizing groupings/ relationships between organisms

Keep in mind:

• Classification systems are artificial. They are developed by scientists to deal with the great diversity of life (currently we’ve named 1.5 million organisms…estimates are that there may be as many as 10 million !!!)

What are some practical uses for a biological classification system?

• Good bug, bad bug?

• Berries at the bog…

History of classification (1):

• 4th century BCE: Aristotle observed and grouped over 500 different animals.

• At the same time, Theophrastus grouped plants as

herbsshrubstrees

But, with the increase in travel and the invention of the microscope…

we needed a more efficient, effective system to deal with the increase in information.

History of classification (2):

• Introducing…. Carl Linnaeus• Founder of modern Taxonomy

Born in SwedenStudied at many universitiesMade 4600km expedition to Lapland, where he identified100 botanical species1735, he published Systema Naturae, his

classification of plants based on their sexual parts

1707-1778

1707-1778

History of classification (3):

Linneaus:• Used structural features of organisms• Recognized that the more features have in

common, the closer their relationship• Created rules for assigning names to

organisms• Used a two word system for identifying each

kind of organisms: known as binomial nomenclature

Binomial nomenclature

• It is a two word Latin namefirst name is the genussecond name is the species

name

• Both together we call the species name

Examples: Genus: Canis, meaning dogSpecies: familiaris, meaning

domesticatedSpecies name: Canis familiaris

Genus: Felis, meaning catSpecies: catus, domestic Species name: Felis catus

The Advantages of Binomial Nomenclature

• Advantage 1: Uses one language because descriptions and different names in different languages = confusion!!!

What is it?

an animal with prickly spikeslives in the watercalled an Itik in Inutitutcalled an ourson in French

It’s a sea urchin!!

Paracentrotus lividus

Advantage 2: Binomial Nomenclature indicates similarities between organisms.

Example:Genus: Ursus, meaning bear

U. maritimus

U. americanusU. horribilis

Ailuropoda melanoleuca Phascolarctus

cinereus

Fooled you…

not bears at all…

Advantage 3: Common names can be confusing and misleading.

Examples: A starfish is not a fishEchinodermata (Spiny-skinned Tide Pool Creatures)

Pisaster brevenspinus

Ringworm is not a wormIt’s a skin infection caused by fungus

Advantage 4: People use many words to name the same organism depending on where they live (same language).

Example: puma = cougar = mountain lion = panther

Felis concolor

Current classification

• Today, we use seven categories by which to classify each type of organism:

• Each category is called a taxon (7 taxa in all)

Kingdom ( most general)Phylum

Class Order

FamilyGenus

(most specific) Species

KPCOFGSCan you find a mnemonic for this?

King Phillip Came Over For Good Spaghetti

Kevin’s Poor Cow Only Feels Good Sometimes

Keep Pond Clean Or Froggy Gets Sick

Examples:

Kingdom Animalia Animalia Animalia

Phylum Chordata Chordata Arthropoda

Class Mammalia Mammalia Insecta

Order Primates Primates Diptera

Family Hominidae Pongidae Muscidae

Genus Homo Pan Musca

species sapiens troglodyte domestica

Kingdom Animalia Phylum Chordata Subphylum Vertebrata Class Mammalia

Order Sirenia

Order Cetacea Order Tubulidentata

Figure 1.14 Classifiying life from Biology, Campbell Reese page 13