What is SPECIES? And HISTORY OF CLASSIFICATION?

SPECIES IS THE BASIC UNIT OF CLASSIFICATION:

DEFINATION OF SPECIES: A species is a group of organisms which can interbreed freely among them the produce fertile offspring, but are reproductively isolated from all other such groups in nature.

In definition of species we must emphasize “in nature” because two organisms related to two different but closely related species can cross-breed under artificial conditions. In such unnatural cross they produces infertile offspring. For example, a cross between a male donkey and female horse produces an infertile offspring i.e, MULE.

HISTORY OF CLASSIFICATION SYSTEM:

The earliest known system of classification of organisms comes from the Greek philosopher Aristotle. He Classified  all living organisms known at time as either in the group ‘plantae’ or in ‘amimalia’.



In 700s, Abu-Usman Umer Aljahiz described the Characteristics of 350 species of animal in the Book.He wrote about life of ants.