Diversity in Living world

DIVERSITY IN THE LIVING WORLD (BIODIVERSITY)

From a current estimation ,approximately 1.7 million species have been scientifically named and classified. These include nearly 1.2 million animals and over 0.5 million species of plants.

Amongst animals, insects form the largest group i.e over1025000 species . It is estimated that majority of species diversity is continued to tropical rain forests and huge diversity exist in under water reef formations in tropical oceans.

Existing living species are the the outcome of about 3.5 billion years of evolutionary process on this earth.Nearly 15000 new organisms are discovered every year. It is not possible to find out an organism of know characteristics from the vast numbers of organisms.

A clearer understanding of this huge variety of organisms can be studies by dividing these into smaller groups of sub groups and each comprising of oganisms with more or less similar characters. This method of placing organisms into groups or sub groups depending upon extent of similarities and differences is called classification. 

The division of organisms into different groups follow certain rules,that is why the term called taxonomy is used for classification of organisms following certain rules or principles.The term taxonomy was coined by A P de Candolle. 

NEED FOR CLASSIFICATION

There are millions of plants and animals varying greatly in their form ,structure and complexicity. It is impossible to study all of them individually . To make the study of organisms possible and easier, scientists have divided organisms into different ranks or categories on the basis of similiarities and differences. 

This inspite of great diversity amongst organisms,they have been arranged in very systematic manner and this arrangement has made it possible to know in details about each group of plants and animals, By looking at their category we can have fair idea about the characters of hundreds of individual placed in that category. 

As we go up in the category the number of common characters goes on decreasing. It is just like systematically arranged library where we can easily find out the required book, in the same way if the organisms are arranged according to a system,it makes their study easy.Some important needs are :

1)   It is essential to understand the inter relationship among different group of organisms

2)   It serves as a base for the development of the other biological sciences like biogeography

3)   Various applied biology fields also depend upon exact idectification and classification.