Knowledge about Plant Science, Animal Science and Conservation Measures in Ancient India have not received in-depth attention of the scholars. The present book tries to project the ancient Indian knowledge in this branch of study covering original source books in regional language like Tamil, Malayalam, Kannada, Tai-Ahom, old Assamese and others alongside Sanskrit. In the present book, the author states that the outlying spirit of unity among the people of different regions is not only expressed in terms of political unity but a strong sense of commonness always works through cultural practices and almost identical heritage of knowledge system. Science or we may call it proto- science is a common heritage of the Indians.