CLASSIFYING ORGANISMS
1.Classification is the process of grouping
things based on their similarities.
2. Classification systems are always based
on observable characteristics
(characteristics you can observe through
your senses).
• Biologists use classification to organize living things
into groups so that the organisms are easier to study.
3.Taxonomy is the scientific study of how living things
are classified.
4.A taxonomist is a scientist who classifies living
things.
Why do scientists classify?
Classification systems organize living things in a logical,
and meaningful way. This makes the study of living things
easier.
• Biologists have identified more than 2.5 million different
types of living things to date.
•Some estimate that there may be at least another 7
million different kinds of organisms living in tropical rain
forests and deep in the oceans that have not yet been
discovered.
5.To bring order to this great diversity of living things, we
call BIODIVERSITY, biologists have developed systems of
classification.
Early Classification Systems
1. Grouped organisms as to whether they were beneficial or harmful
2. Recognized 5 animal groups:
a. domestic
b. wild
c. creeping
d. flying
e. sea animals
6. First scientist to use a classification system was the Greek
scholar, Aristotle.
Aristotle:
•
4 th century
•
Greek philosopher
•
Divided organisms into 2 groups –plants and animals
•
Divided animals into how they moved (behavior)
a. walk, crawl, or run
b. fly
c. swim
7. Carolus Linnaeus- 1750s
• Classified organisms based on similarities
in form and structure.
• Examined the organism’s internal anatomy
as well as its outward structure.
Puma, Cougar, or Mountain Lion?
8.Carolus Linnaeus developed a system for
naming organisms called binomial
nomenclature. In this system, each organism
is given a two part name, called the scientific
name.
Ex. Felis concolor
Genus
species
(general)
(specific)
Binomial nomenclature
Name consisting of two terms
A system of terms
“ a system of names consisting of two terms”
A two-name naming system
Genus-species
9.The scientific name of an organism includes the genus and species.
10.The scientific name is written in Latin, because it was the language
used by scientists when the naming system was invented. The language
is also no longer used so it will not change and the names will also never
change.
• Genus is the first part of the scientific name. It is a classification
grouping that contains similar and closely related organisms.
• Example: Felis (genus) includes pumas, ocelots, and housecats.
They all share the following characteristics: sharp, retractable
claws and hunting behaviors
Genus Felis
• sharp, retractable claws
• behaviors such as hunting other
animals
• Species is the second part of the scientific name.
• A species is a group of similar organisms that can mate and produce fertile
offspring.
• A species name often describes a distinctive feature of an organism, like its
color or where it lives.
• Example: Felis concolor
concolor means “the same color” in Latin; like a puma which is
all one color;
Example: Felis pardalis
paradalis means “spotted like a panther” in Latin; like an ocelot
which has a spotted coat;
concolor =
same color coat
Felis concolor
Species - ?
paradalis =
spotted coat
Felis paradalis
domesticus =
house cat
Felis domesticus
• Scientific name is written in italics or each part must be underlined.
Example: Felis concolor OR Felis concolor
• Genus is written with a capital letter
• Species is written with a lowercase letter.
• The genus is written first and the species is written after it;
• Examples
Felis domesticus = house cat
Pinus taeda = loblolly pine
Musca domestica = housefly
Ursus horribilis = grizzly bear
LEVELS OF CLASSIFICATION
• Linnaeus’ classification system uses a series of seven levels to
classify organisms.
• The more classification levels that two organisms share, the more
characteristics they have in common.
• The kingdom is the broadest classification level; species is the most
specific.
The Seven Levels of Classification
according to Linnaeus
1. Kingdom
Kings
2. Phylum
Play
3. Class
Cards
4. Order
On
5. Family
Fat
6. Genus
Green
7. Species
Stools
broadest
most specific
Domains:
1. Archaea
2. Eubacteria (Bacteria)
3. Eukaryota (Eukarya)
The Modern Levels of Classification
1. Domain
Do
2. Kingdom
Kings
3. Phylum
Play
4. Class
Cards
5. Order
On
6. Family
Fat
7. Genus
Green
8. Species
Stools
broadest
most specific
Domain
Domain
Eukaryota (Eukarya)
great horned owl
THIS CATEGORY…
IS MUCH LIKE THIS
CATEGORY.
Kingdom
Planet
Phylum
Hemisphere
Class
Continent
Order
Country
Family
State
Genus
City
Species
Street Address
Academy Road
Caldwell
What is the largest and most general level
of classification?
1. Species
2. Phylum
3. Kingdom
What is the two- part naming system
devised by Carolus Linnaeus in the 18th century ?
1. Classification
2. Binomial nomenclature
3. Dichotomous system
The science of grouping living things based on
similarities is called _____.
1. classification
2. taxonomy
3. nomenclature
In the scientific name Felis concolor, “ concolor”
refers to
1. genus
2. family
3. species
Which of the following is the correct form for
writing the scientific name of an organism?
1. Felis Concolor
2. felis concolor
3. Felis concolor
4. Felis concolor
Prokaryotic cell – does
not have a nucleus
Eukaryotic cell- has
a nucleus
Heterotrophic – does
not make its own food
Autotrophic – makes
its own food
Unicellular – made
up of one cell
Multicellular – made
up of many cells
The Six Kingdoms of Living Things
Archaebacteria
Eubacteria
Protists
Fungi
Plants
Animals
1. Archaebacteria –”ancient bacteria” live in extreme
conditions like hot springs, your intestines, in molten rock
on the ocean floor; “the extremophiles”
prokaryotic; unicellular; autotrophic/heterotrophic
2.
Eubacteria – live in non-extreme conditions like your throat,
in yogurt and cheeses; some are harmful, but most are
helpful;
prokaryotic; unicellular; autotrophic/heterotrophic;
Protists – the “junk drawer” kingdom;
eukaryotic; unicellular/multicellular;
autotrophic/ heterotrophic