Question

Why do we see different types of organisms around us ?

Answer 1

The diversity (variety) of organisms on the earth are due to the process of evolution. Millions of years of evolution has resulted in so much of variety on the earth.
Evolutionhe is possible because of the genetic variability. The genetic variability arises due to the changes occuring in the DNA molecule.
Among the varients best suited organism is selected by the nature which we call "Natural Selection ".
Sometimes chance selection of a variety can also occur which we call "Genetic Drift".
All these evolutionary process have brought such variety on the earth surface.