It only makes sense if you know Major League Baseball and its minor league affiliates, and I only mentioned AA and AAA levels. If Pokemon had more levels of evolution, let's say, 7, the evolutionary line would go like this:
Blue Jay --> Canadian --> Lugnut --> Blue Jay --> Fisher Cat --> Bison --> Blue Jay
It has nothing to do with biological growth, but more of experience. If a baseball player played for the New Hampshire Fisher Cats becomes good, and gets more experience, he gets called up to the Buffalo Bisons, and then ultimately makes it to the big show in the Toronto Blue Jays.
All I am saying is that Gamefreak could technically make an evolutionary line that doesn't make sense when you first see it, because the evolved form isn't a bigger version of the previous form, but would only make sense if you get the reference.
Besides, do you know what is the most dangerous animal that kills the most humans? Mosquitos, unless you count humans killing each other with all that war stuff going on, but if it was another animal, it would be mosquito. All I am saying is bigger isn't always better.