Why did it become necessary to create a classification of living organisms?

It is known that many species of animals appeared as a result of evolution and this phenomenon is very easy to explain. Over time, animal populations became larger and larger and the need for the development of new territories began to arise. Living in different climatic and geographical conditions, animals adapted to new conditions and changed their way of life. Over time, studying animals, it became necessary to divide them into separate species, which have obvious differences, in order to clearly distinguish between their features.