Ducks on a pond

So I used to have these four identical ducks. I've always encouraged them to do their own things, but even so, three of them have remained remarkably similar: impossible to tell apart. One of them, however, took up cycling. Did really well. Turned pro. And then he changed. A couple years ago, you couldn't tell these four apart, but I guess that's what cycling will do for someone. It's obvious to me which one it is, but can you tell?


Yep, it's the one with the "Who me? Performance enhancing drugs?" look on his face. Oh yeah, he's got a bike helmet on, too.