Evolution is an interdisciplinary Science and extends to diverse fields such as Zoology, Botany, Earth Science and Geography. The present title is an effort to Summarize the basic concept and principles of the subject, to present the elementary factual information with which a Person to be competent in the field should be familiar, and to show how these principles and facts may be applied in a practical way to the interests and welfare of man. Although the book relates especially to animals, enough material given covering plants to bring out their essential Place in the system of nature. The Present title is intended for beginners who wish to understood the fundamentals of Evolution. The whole gamut of subject has been described in a simple and systematic manner suited for readers who have not been exposed sufficiently to the subject. It is an adequate text for all requirement in this area for the students of all Indian Universities. The primary aim throughout has been clarity, simplicity and the high standard. It will be a valuable study aid to teachers, students and research scholar in the related field.