I know a couple of people who are co-authoring a book, and they have been debating how to go about distinguishing between the two of them in their content. They have an outline of topics that they are discussing, and each is providing their own voice/commentary on each topic individually. As they get ready to merge their content, how should they go about identifying which comments are from which author?
EDIT: To be more specific, the male co-author is a nature photographer, and the female is a zoologist. They met online and agreed to do a seven month trek through Africa, with each chronicling their observations independently, without seeing what the other wrote. At the end of it all, they are merging their content to show each person's perspective. Basically, each chapter is a different incident that occurred during their journey together.