Thanks, everyone! I'm really glad you enjoyed it! And I'm happy to see people picking parts of it away too - it's always nice to get some constructive criticism!
As for whether they are actual evolutions or not, have a read of this. I'm a firm believer in that. Basically, if it's not explicitly stated or at least heavily alluded to within the work of fiction, then it's up to the reader to decide what really happened. I didn't make it completely clear whether they actually evolved or not so it's up to each individual reader to make that decision for me. =)
Of course, sometimes, I will just say what things are meant to show, just to make things clearer. =P