1. Genetic drift:- variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce.?????2. Speciation:- the formation of new and distinct species in the course of evolution.?????3. Heridity:- the passing on of physical or mental characteristics genetically from one generation to another. ?????4. Natural selection:- the process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin, and it is now regarded as be the main process that brings about evolution.☺️☺️☺️☺️☺️☺️☺️☺️☺️