Taxonomy

Natures filing system?

Learning Outcomes

• Define the term “taxonomy”

• List the different levels of taxonomy in order

• Name 4 different species using their full taxonomic name

• Relate species differences to selective processes (previous session!)

Why classify?

• Helps humans to make sense of the abundant biological diversity that exists in nature.

• Enables us to categorise what is out there!

What is Taxonomy?

• Science of naming organisms and assigning them to groups

• Looks at different and common species

• Looks at relationships of

species at different levels

- general

- specialised

Why is Taxonomy Useful?

• Allows us to identify new species!

• Taxonomists spend their time searching for previously unknown organisms, determining their relationships to known organisms, and giving them names.

• Without classification, this would not be possible.

So Who is Involved?

Aristotle

• Realised that you had to observe various characteristics, not just one

• Considered to be 1st person to group organisms in ways that made sense!

• Involved in the terms “substance”, “species” and “genus”

Ernst Haeckle

• Discovered, described and named thousands of new species

• Mapped a genealogical tree relating all life forms

• Coined many terms including phylum, phylogeny, ecology and the kingdom Protista

Carolus Linnaeus

• Divised system for clear and easy descriptions of plants, animals and minerals

• Classified organisms using

a two part latin name –

binomial classification

• System still used by scientists today!

The Seven Levels

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

• Kings

• Play

• Chess

• Only

• For

• Good

• Sports!

Example: Grizzly Bear!

Kingdom

• The starting point of species classification

• Divided into 5 kingdoms

The 5 kingdoms are :

• Monera (Bacteria)

• Protocista (Protozoa)

• Fungi (Mushrooms, Mould)

• Plantae (Ferns, Herbs, Tres)

• Animalia (Fish, Birds, Insects)

Phylum

• Each kingdom is subdivided into smaller, more specific groups called phyla.

• Groups with general common features (shells, legs, spine)

e.g. birds, mammals, fish (spine)

snails, limpets, lobsters (shells)

Class

• Each phylum is subdivided into smaller groups called classes.

• Divides groups into general common features

e.g. Mammals – bears, mice, elephants, dolphins

• Base of most fossil studies!

Order

• Each class is subdivided into smaller groups called orders.

• Groups of individuals with a major similar quality

e.g. Carnivora = cats, dogs, weasels

= meat eaters!!!

Family

• Each order is subdivided into smaller groups called families.

• Major groups of similar organisms

E.g. Felidae = cats

Genus

• Each family is subdivided into smaller groups called genera.

• Group of species very closely related

E.g. Sciurus = Squirrels

Species

• Each genus is subdivided into smaller groups called species.

• Group of similar individuals which can breed freely, but not successfully with other species (hence sub-species).

• The species is the most specific level of classification.

In General

The way the kingdom is broken down is as follows:

• A number of species make up a genus.

• A number of genera make up a family.

• A number of families make up an order.

• A number of orders make up a class.

• A number of classes make up a phylum.

• A number of phyla make up a kingdom.

Scientific Names

• The scientific name of an organism contains two parts

- the name of the genus and

- the name of the species.

• Binomial naming – Linnaeus!

Writing Scientific Names

The rules for writing scientific names:

• CAPITALIZE the first letter of the genus name.

• Do not capitalize the species name.

• Both names must be underlined or italicized.

• Example: human = Homo sapiens

Recognising the groups

• Kingdom: Always starts with a capital letter (e.g. Animalia)

• Phylum: Always starts with a capital letter (e.g. Chordata)

• Class: Always starts with a capital letter (e.g. Mammalia)

• Order: Always starts with a capital letter (e.g. Rodentia)

Recognising the groups

• Family: Always end in “ae”

(e.g. Sciurinae)

• Genus: Always starts with a capital letter and in italics (e.g. Sciurus)

• Species: ALWAYS lower case and italics!!! (e.g. vulgaris)

Recognising the Groups!

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

• Animalia

• Chordata

• Mammalia

• Rodentia

• Sciurinae

• Sciurus

• vulgaris

Example 1: A Dog

• Kingdom: Animalia

• Phylum: Chordata

• Class: Mammalia

• Order: Carnivora

• Family: Canidae

• Genus: Canis

• Species: familiaris

Example 2: A Lion

• Kingdom: Animalia

• Phylum: Chordata

• Class: Mammalia

• Order: Carnivora

• Family: Felidae

• Genus: Panthera

• Species: leo

Example 3: A Dandelion

• Kingdom: Plantae

• Phylum: Tracheophyta

• Class: Anthophyta

• Order: Asterales

• Family: Compositae

• Genus: Taraxacum

• Species: officinale

Over to You!

Using the information you have just gained…

• Organize your sets of cards into order of the seven taxonomic levels

• As a minimum you should get Kingdom, Family, Genus and Species

• Once you have done this, try and work out what your organism is!

Recap!

• Taxonomy is the classification of all organisms

• It allows us to identify new species using common features

• Carolus Linnaeus is the founder of the binomial system, which we use today

• There are seven taxonomic levels

• Each level becomes more specialised as you move down