How did the flightless cormorants come to exist on the Galapagos Islands?

Question

How did the flightless cormorants come to exist on the Galapagos Islands?

Answer 1

when they first arrived they had plenty of food also no preadators so they had no reason to fly. over the years that lessened muscle mass and that lack of flight also changed the bone structure so you end up with what you got today.