vocal repertoire of siamese cats

Hmmm, it's funny, I remember the most vocally varied cat I have ever known was a siamese cat. She was also the most mischievious cat I've known.

cats grouping where they had been previously domesticated

Well, I think you may be right there. I recall the whole pack living in a barn. The kittens were hidden in back of some sort of machinery. They weren't chased away because they kept the population of mice down (which segued into the whole bird/mouse, killed amount, part of the documentary.)