Speciation is a process by which a new species arises. This most commonly occurs when a population of organisms is geographically divided leading them to evolve separately. We have an introduction to evolution that you may be interested in reading; https://www.physicsforums.com/showthread.php?t=543950
Homework must go in the homework section, also, posting a title and a question without any explanation, no source, and no effort on your part is not acceptable.