Chapter 7 Classification – putting things into orderly groups based on similar characteristics.

Chapter 7

Classification – putting things into orderly groups based on

similar characteristics

Why Classify ?????

• Makes it easier for biologists to answer

» How many species are there?

» What are the defining characteristics of each species?

» What are the relationships between these species?

Before 1600’s…..

• Scientists divided organisms into 2 groups:

• Plants

• Animals

1700’s….

• Carolus Linnaeus – founded modern TAXONOMY

• Taxonomy – the science of describing, classifying, and naming living things

Classification Today…..

• 8 level system based on shared characteristics

• D,K,P,C,O,F,G,S

Branching Diagrams…..

Levels of Classification…..

• Kingdom (s)

• Phylum – Phyla

• Class(es)

• Order (s)

• Family – Families

• Genus – Genera

• Species

Two-Part Names…..

• Linnaeus gave each species a 2 part name

• Part One – Genus Name

• Part Two – Species Name

• Both are Italicized (or underlined)

• Part One is Capitalized

• Part Two is NOT capitalized

Binomial Nomenclature…..

• Human – Homo sapiens

• Asian Elephant – Elephas maximus

• Skunk - Mephitis mephitis

• Gray Wolf - Canis lupus

• Dog - Canis familiaris

• Cat – Felis catus

Dichotomous Keys…..

• Special identification aid that uses sequential pairs of descriptive statements