classification. why do we classify? early classification 2000 years ago, greek and chinese...

CLASSIFICATION

Why do we classify?

Early Classification

• 2000 years ago, Greek and Chinese Scientists classified animals based on _______________

• 350BC, Aristotle came up with a more complicated system based on many things including _____________________________.

Taxonomy

• ____________________________________________________________________________

John RayBiologist in the 1600sPlaced organisms in a hierarchy based on categories and subcategories.

Father of _____________________

Carolus Linnaeus• In the late 1700s

catalogued plants and insects.

• Developed basis for modern taxonomy using Latin words to describe organisms.

• Why Latin?

Classification Keys

• Used to help identify organisms based on _____________________________________.

• To identify something, you decide which of the two descriptions fit.

• One description will lead to an ____________ ______________ and the other will lead to more ________________________________.

• You will continue doing that until you find the organism’s name.

Example: Dichotomous Key

Binomial System of Nomenclature• Also known as the ______________________.• Specific name of an organism using two Latin

words.• The first word is the ______________. It is

capitalized and italicized/underlined.• The second word is the ________________. It is

lower case and italicized/underlined.Example:Humans = Homo sapiens*the genus and specific epithet make up the

species name.

Larger Divisions of Classifications

Each division is referred to as a “taxon”.

Most General

Most Specific

Specific names are important because…

Changes since Linnaeus’ time...

• Over 2.5 million organisms have been discovered.

• Better tools and methods.• Based on evolution

FRIENDS Dichotomous Key

1 (a) This person is a female.(b) This person is a male.

Go to 2Go to 3

2 (a) They have blonde hair.(b) They don’t have blond hair.

Go to 4Monica

3 (a) This person got married.(b) This person never got married.

Go to 5Joey

4 (a) This person slept with Brad Pitt.(b) This person never slept with Brad Pitt.

RachelPhoebe

5 (a) This person studied dinosaur bones.(b) This person never studied dinosaur bones.

RossChandler