Seriously...
I read a book when I was younger called "Descent of Woman" by Elaine Morgan. It made what I, as a layman, thought was a very plausible case that humans evolved in a shoreline/shallow water environment.
Keep in mind that most professionals in this field scoffed at her, and her overall theory has some serious holes, but it was still interesting, and I still think the idea of some aquatic adaptation has its points.