The Aquatic Ape Hypothesis of Elaine Morgan is a classic "just-so" story that attempts to explain the evolution of modern humans by claiming that our ancestors once lived in water. It's a typical adaptationist perspective on biology since it begins with the assumption that every phenotype of humans must have been due to natural selection.
Morgan gave a talk last month sponsored by TED. It's posted at: Elaine Morgan says we evolved from aquatic apes. You should watch it if you are interested in the Aquatic Ape Hypothesis. In addition to being a good example of (false) adaptationist thinking, it's a good example of how a skilled journalist makes a "scientific" case to a general audience. The audience loved her. She gets an enthusiastic standing ovation at the end.
I didn't realize that Elaine Morgan was relying so much on attacking scientific conspiracy in order to bolster her beliefs. Many of her arguments sound similar to those of the Intelligent Design Creationists. Judging by the reception she gets, there's a lot of reasonably intelligent people out there who are willing to buy into the idea that scientists suppress knowledge of things they don't like just because they don't like them.
[Hat Tip: John Hawks]