I think that it is no wonder that the first mermaid stories originate from Assyria, and I have a theory about that. In the Persian Gulf there is an aquatic creature similar to a Manatee called a Dugong. Apparently, the vagina of a Dugong is about the same size and texture of that of a human. So, what happened was that fishermen or pearl divers out on their boats for an extended period of time caught a Dugong and being horny young men, of course fucked it. However, being men there was no way that when they got back into port that they were going to boast about fucking an ugly aquatic mammal so instead in typical fashion they made up this ridiculous story about a beautiful, beguiling and winsome half woman half fish (wink wink). Of course, none of them would ever tell the truth and over the 4000 or so years since this first occurred the story has spread from culture to culture and taken on the various permutations on the theme that you describe in your article. Anyhow, that's my theory and even today I can hear the first lot of them conspiring together 'to get their story straight'.