Name______________________________________ Biology-_____ Date __________
Taxonomy: (Gr. taxis, "arrangement, order", nomos, "law")
Taxonomy: (Gr. taxis, "arrangement, order", nomos, "law")
Our earth is inhabited by many different types of organisms (living things), from trees and
grasses to all sorts of birds, insects, bacteria and more. Different organisms come in all sorts
of shapes, sizes and colors, with each one having a unique form. Despite the great diversity,
there is much unity in life as well, and organisms can be grouped together based on how
closely related they are.
In order to have a better understanding of the organization of life on earth,
scientists in the past developed various ways of classifying (or grouping) the different
organisms on earth, and to assign each organism and their groups specific names. In the
18th century (about 300 years ago), a scientist named Carolus Linnaeus developed a
Binomial nomenclature, or naming system, that is still in use today. In this binomial
system, organisms are given scientific names with two parts: the genus of the organism,
which is the name given to a group of very similar organisms, and the second the species,
which is specific to that one organism.
Binomial nomenclature:
Our earth is inhabited by many different types of organisms (living things), from trees and
grasses to all sorts of birds, insects, bacteria and more. Different organisms come in all sorts
of shapes, sizes and colors, with each one having a unique form. Despite the great diversity,
there is much unity in life as well, and organisms can be grouped together based on how
closely related they are.
In order to have a better understanding of the organization of life on earth,
scientists in the past developed various ways of classifying (or grouping) the different
organisms on earth, and to assign each organism and their groups specific names. In the
18th century (about 300 years ago), a scientist named Carolus Linnaeus developed a
Binomial nomenclature, or naming system, that is still in use today. In this binomial
system, organisms are given scientific names with two parts: the genus of the organism,
which is the name given to a group of very similar organisms, and the second the species,
which is specific to that one organism.
Binomial nomenclature:
For example, humans would have the scientific name Homo sapiens (where Homo
is the genus and sapiens is the species), and the African lion has the scientific name Panthera
leo. Besides developing a naming system, Linnaeus developed a hierarchical system for
classifying all the organisms on earth. This system provided a structure with which we can
group closely related organisms to better study them, and to identify new species of plants,
animals and microorganisms that are still being discovered. The system is considered
“hierarchical” since it consists of layers of groups, with a group (or taxon) of a higher level
encompassing several groups of lower levels within it. The main taxonomic levels, in order
of decreasing size, are (with the example of the leopard given):
Domain Eukarya
How do I remember all the taxons?
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Carnivora
Family Felidae
Genus Panthera
Species Pardus
Scientific Name: Panthera pardus
Taxon:
For example, humans would have the scientific name Homo sapiens (where Homo
is the genus and sapiens is the species), and the African lion has the scientific name Panthera
leo. Besides developing a naming system, Linnaeus developed a hierarchical system for
classifying all the organisms on earth. This system provided a structure with which we can
group closely related organisms to better study them, and to identify new species of plants,
animals and microorganisms that are still being discovered. The system is considered
“hierarchical” since it consists of layers of groups, with a group (or taxon) of a higher level
encompassing several groups of lower levels within it. The main taxonomic levels, in order
of decreasing size, are (with the example of the leopard given):
Domain Eukarya
How do I remember all the taxons?
Kingdom Animalia
Phylum Chordata
Class Mammalia
Order Carnivora
Family Felidae
Genus Panthera
Species Pardus
Scientific Name: Panthera pardus
Taxon:
Organisms in the same group share various common features (such as having fur, a hard
shell, scales, gills, etc.). Larger groups (such as domains, kingdoms, or phyla) have more
generally shared features by many organisms, while smaller groups at the lower levels
(species) have features that are very specific to just a small group of organisms. In this
lesson, we will find out more about how organisms are classified into various groups by
learning how to use a dichotomous key to identify specific organisms in a collection of
different ones.
Dichotomous Key:
Organisms in the same group share various common features (such as having fur, a hard
shell, scales, gills, etc.). Larger groups (such as domains, kingdoms, or phyla) have more
generally shared features by many organisms, while smaller groups at the lower levels
(species) have features that are very specific to just a small group of organisms. In this
lesson, we will find out more about how organisms are classified into various groups by
learning how to use a dichotomous key to identify specific organisms in a collection of
different ones.
Dichotomous Key:
Name______________________________________ Biology-_____ Date __________
A. Find and match the scientific names of the organisms’ common names by using the following key:
Dichotomous Key Practice
1. animal
go to 2
Common
Name
not an animal
2. has wings
no wings
3. has feathers
no feathers
4. flies high
does not fly high
5. often yellow
not yellow
6. lives in water
lives on land
7. has fluffy fur
no fluffy fur
8. common pet
not a common pet
9. has fins
no fins
10. razor sharp teeth
pegged, pointy teeth
11. green
not green
12. grows tall
does not grow tall
13. can be poisonous
not poisonous
Scientific Name
1. dog
2. shark
3. rose
4. skunk
5. turkey
6. dolphin
7. eagle
8. canary
9. oyster
10. mosquito
11. mushroom
12. cow
13. pine tree
14. ivy
Classification Table Practice
The table below shows the complete classification of
several species of animals. Use the table to answer the questions that follow.
1. What is the scientific name for
the house cat?
2. What is the scientific name for
the gopher?
3. What is the scientific name for
the red fox?
4. What is the complete
classification of Vulpes fulva?
Organism
House cat
Red Fox
Dog
go to 11
go to 3
go to 6
go to 4
Ochloerotatus taeniorhynchus
go to 5
Meleagris gallopavo
Serinus canaria
Haliaeetus leucocephalus
go to 9
go to 7
go to 8
Bos taurus
Canis familiaris
Mephitis mephitis
go to 10
Haematopus ostralegus
Carcharodon carcharias
Tursiops truncates
go to 12
go to 13
Pinus ponderosa
Rhus toxicodendron
Boletus edulis
Rosa sylvestris
Wolf
Gopher
Fly
Kingdom
Animalia
Animalia
Animalia
Animalia
Animalia
Animalia
Phylum
Chordata
Chordata
Chordata
Chordata
Chordata
Arthropoda
Class
Mammalia Mammalia Mammalia Mammalia Mammalia
Insecta
Order
Carnivora
Carnivora
Carnivora
Carnivora
Rodentia
Diptera
Family
Felidae
Canidae
Canidae
Canidae
Geomyidae Muscidae
Genus
Felis
Vulpes
Canis
Canis
Thomomys
Musca
Species
domesticus fulva
familiaris
lupus
bottae
domestica
5. From the table, which two animals are most closely related? Explain.
6. At what classification level does the evolutionary relationship between gophers and house cats diverge?
7. How does the table indicate that a dog is more closely related to a red fox than to a house cat?