Granted, a newborn's wings started to separate out a few months down the line for mercifully obvious reasons. But no. Most people with avian DNA didn't spontaneously shift in their mid twenties. Then again, Desmond wasn't most people.

"Uh...Shaun?" Yeah. That freaking out thing? Already there. He grunts in surprise when Shaun shoves his shirt up to his neck. "The fuck?"

Even with all his squirming to get his shirt back down, the bruising, the twin lumps housing the developing joints, the swollen bits of skin on his shoulders and neck that look suspiciously like feather follicles instead of ones for hair... If it's not a pair of wings starting to develop, then it would be a surprise.