How did the visit to the galapagos islands affect darwin's thoughts on evolution?

Darwin's visit to the Galapagos Islands enhanced his thoughts on evolution in many ways. it helped Charles Darwin discover several species of finches, which varied from island to island. This helped him develop his theory of natural selection due to their features, on each specific island.

For instance, one species may have a rather larger beak for cracking nuts and whatnot, while the other species has a small beak for much smaller foods. This gave Darwin the thought of Natural Selection, within evolution.