You're making the faulty assumption that those are descended in a line from the first to the last. In actuality they branch off in every direction. The actual linear ancestry is not known. Additionally, some features like body size can be scaled up or down fairly easily without major genetic changes (look at a toy poodle and a mastiff--you would apparently say they aren't related by common descent).
Argue with Ichemonuen (sp?)
HE'S the one that posted this thing before, letting folks ASSUME that they all linked together.