Classification Of Living Organisms

Biologists have examined and described more than 1-8 million kinds of living organisms. There are still many more to be discovered and described. We must therefore have a meaningful way of classifying, identifying and naming them. Aristotle (384-322 sc), a Greek philosopher, was the first to make an attempt to classify living organisms. The present method of classifying and naming living organisms is based on the work of Carolus Linnaeus (1707-1778), a Swedish naturalist. The study of the general principles of classification is known as taxononry or systematics

Method of Classifying

To classify organisms into main groups, biologists look for important features that are shared by a large variety of organisms. These teatures should have a similar origin, structure and position.

Organisms with certain important features in common are then put together into one group. Divisions and subdivisions within a
main group are based on progressively less im portant features.

Hierarchy of Living Organisms

The largest group of organisms is the kingdom. Each kingdom is split into smaller groups, and these groups into even smaller groups, and so on. The arrangement of living organisms in this hierarchy from the highest level to the lowest is as follows:

1.Kingdomn
2.Phylum or Division (plants)
3.Class
4.Order
5.Family
6.Genus
7.Species

Sometimes intermediate levels are added.
These are usually identified by prefixes such as sub - and super, eg. subphylum and superclass.