Do you remember what you looked like 10 years back? You may well be cringing right now, but the truth is that most people are leaps and bounds from the person they were a decade ago. Our hobbies shift, our personalities evolve, our dreams change, our values differ. But the most dramatic and apparent transformation is that of our appearance. And the same goes for celebrities.Take Nick Jonas, for example. Ten years ago, he was the youngest and most adorable third of the Jonas Brothers. He would go on to act in movies and plays, embark on a solo music career, and take photos in exceedingly low-rise jeans. And now, he's the guy who's too cool to confirm that he dated Kate Hudson , the man whose onstage bulge we shamelessly ponder , and indubitably the sexiest Jo Bro.So, in honor of his 24th birthday on September 16, we decided to track exactly how Nick's look has evolved over the last decade. Here is the physical transformation of Nick Jonas, in 24 slides.