Taxonomy

Taxonomy

Chapter 16

Classifying

Taxonomy: The science of classifying

Classify: to group ideas, information, or objects based on similarities.

Name places you been to that have classified things

Early History of Classification

Aristotle developed a system to classify living things. Thought all living things could be either Plant or

Animal kingdom

Kingdom: The first and largest category

His problem though…

Grouped them according to physical traits

Then used things like: lived, blood, reproduced, wing types

But there were too many exceptions Ex: Frogs

Another problem develops

Sometimes, an organism has a different name in each country it lived in

Or even in the same country

Examples:

A new system emerges… Scientific Naming

To counter that problem scientists gave organisms names that described them in great detail

Example: Spearmint plant Scientific name: Mentha floribus spicatis, foliis

ablongis serratis

Good thing the next guy came along…

Carl Linnaeus and Binomial Nomenclature

Carl Linnaeus: Swedish scientist who created a simpler, unique way to name organisms

Binomial nomenclature: gives a two-word name to every organism Binomial means “two names” Much like a first and last name

What’s in a name?

The first word of an organism’s name is the genus Genus: a group of different organisms that have

similar characteristics.

The second word is the species group Species: the smallest, most precise classification

category Organisms in the same species can mate an produce

fertile offspring

Soy

Carp

Example of how it works

Canis familaris: The domesticated dog

The first word(the genus) is always capitalized while the second word(the species) is always lowercased.

Both names are written in either italics or underlined

It uses Latin because when he developed it, Latin was used by educated people

Today, Latin is used internationally because a lot of languages are based on Latin roots

In this system no two organisms have the same name.

This way everyone can know the difference between a dog Canis familaris and a gray wolf, Canis lupus

Modern Classification

Linnaeus and Aristotle both developed their systems based on physical characteristics

Today, we can classify beyond that using DNA and cell structure.

They also study fossils, they examine and compare ancestors to existing organisms.

Phylogeny

From this new information, we create their phylogeny

Phylogeny: its evolutionary history or how it changed over time.

Phylogeny tells scientists who the ancestors of an organism were

Classification system used today separates organisms into six kingdoms

Animal Plant Fungi Protists Eubacteria Archaebacteria

Six Kingdoms

Groups within a Kingdom

Every organism is placed into a kingdomAfter that into a PhylumEach phylum is separated into ClassesClasses are separated into OrdersOrders are separated into FamiliesFamilies separated into GenusA genus separated into a Species

Kingdom

Phylum

Class

Order

Family

Genus

Species

Assignment: Design an Mnemonic Acronym

King KingdomPaul PhylumCried ClassOut OrderFor FamilyGood GenusSoup Species

Common Names and Scientific Names

Functions of Scientific Names

They help scientists avoid errors in communication

Organisms with similar evolutionary histories are classified together

Scientific names give descriptive information about the species

Scientific names allow information about organisms to be organized and found easily and efficiently

Dichotomous Keys Dichotomous Key: a detailed list of characteristics

used to identify organisms and included scientific names

Keys are arranged in steps with two descriptive statements at each step

You keep answering questions until you get to the scientific name of your organism

You must always start at the beginning of the key