4.3.1 Classification of Species

Question 1

What is taxonomy and the classification of species?

Answer 1

Taxonomy is the practice of biological classification
The biological classification system enables us to arrange species into groups based on their evolutionary origins and relationships
In this hierarchical system there is no overlap between groups and each group is called a taxon (plural taxa)
By grouping organisms into taxa it can make them easier to understand and remember
There are several different ranks or levels within the hierarchical classification system used in biology
Multiple smaller taxa can be put into one larger taxon

Question 2

What is hierarchical classification?

Answer 2

The hierarchical classification system of organisms in biology is used to organise and group similar organisms together so that they can be more easily understood
There are several taxonomic ranks that exist
All taxonomic ranks or ‘taxa’ make up a ‘taxonomic hierarchy’
Species is the lowest taxonomic rank in the system
Similar species can be grouped in a genus (plural genera)
Similar genera can be grouped in a family
Similar families can be grouped into an order
Similar orders can be grouped into a class
Similar classes can be grouped into a phylum (plural phyla)
Similar phyla can be grouped into a kingdom
Similar kingdoms can be grouped into a domain
Domains are the highest taxonomic rank in the system
There are a few different rhymes that exist to help you remember the different ranks in the taxonomic classification system. A couple of examples are given below but you could always make up your own!
The first letters of all the different ranks below the domains can be remembered as:
Kings Play Chess On Fancy Gold Squares
Kittens Pounce Clumsily On Furry Green Spiders
Kingdom Phylum Class Order Family Genus Species

Question 3

What is the classification of organisms in the Eukarya domain?

Answer 3

Eukarya is the domain of all eukaryotes, distinguishable from Bacteria and Archaea which are both prokaryotic domains
Just like the other domains, Eukarya contains the taxonomic hierarchy of kingdom, phylum, class, order, family, genus and species
A wolf is an example of an organism in the Eukarya domain
It can be classified further into its kingdom, phylum, class, order, genus and species
A wolf belongs to the following taxonomic groups:
Domain: Eukarya
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Canis
Species: lupus
The Hibiscus rosa-sinensis (a colourful flowering plant) is another example of an organism in the eukarya domain
It belongs to the following taxonomic groups:
Domain: Eukarya
Kingdom: Plantae
Phylum: Angiospermae
Class: Dicotyledonae
Order: Malvales
Family: Malvaceae
Genus: Hibiscus
Species: rosa-sinensis