The arrangement of organisms into groups and sub-groups on the basis of similarities and dissimilarities is called classification.
Over 1.5 million types of animals and over 0.5 million types of plants are known to biologists.
The range in complexity from small and simple bacteria to large and complex human beings.
Some of the organisms live in the sea, some on land, some walk, others fly and still others are stationary.
All the members of a species, living in specific habitats are called the “Population”. A group of parrots living in a tree is called a parrot population.
The branch of Biology which deals with scientific naming and classification of organisms are called taxonomy.
The branch which deals with classification and also traces the evolutionary history of organisms is known as systematics.
The main aims of this branch are;
Classification is based on relationships among organisms and such relationships are obtained through similarities in the form or structure.
These similarities are seen in
The similarities suggest that all organisms are related to one another at some point in their evolutionary histories. However, some organisms are more closely related than others.
Sparrows are more closely related to pigeons than to insects. It means sparrows and pigeons have common evolutionary histories.