When the ancestral finch left the Galapagos island that it originated in, it needed to adapt for survival. The ancestral finch had a short, stocky beak that was not ideal for obtaining food. As time went on, the finch began to develop a larger, thicker beak that allowed it to forage and eat more efficiently. So, in the longterm, the Large Ground Finch evolved to have a large, strong beak to better eat seeds.