Classification in biology.

Classification refers to the sorting of organisms into groups based on their common characteristics. The first scientist to classify organisms is Aristotle.

Aristotle classified organisms into two groups; plants and animals. He classified animals based on their habitat thus those that live on land as terrestrial animals(in which we humans fall), those swim in waters as aquatic animals and those that fly in the air as aerial animals. Aristotle's order of classification couldn't stand the test of time because it couldn't establish the natural relationship between organisms.