to places in South America and the Pacific, and Darwin pla tow looked carefully at the animals and plants in all these different places.
At this time, most scientists believed that species did not change. How did they explain fossils that were different s from living species? They thought that from time to time a big change happened to the Earth, and then the old species died and new species took their place. So an old fossil and a new species could not come from the same family. But Darwin began to think that perhaps this was not true. In South America and in the Galapagos Islands, Darwin looked at some small birds called finches. He saw that the finches in the Galapagos Islands were not the same as the finches in South America; what is more, s the finches of one and were different from the finches of another island Finches that ate big seeds had big strong bills; finches that ate insects had narrow bills. Perhaps, Darwin thought, these birds were once the same, but because they lived in different places and ate different food they slowly changed After he came back from his travels, Darwin spent a long time studying, reading, and writing about his ideas.