Which islands did Charles Darwin visit that greatly influenced his theory of evolution?

Charles Darwin visited the Galápagos Islands, an Ecuadorian archipelago whose wildlife helped shape his thinking about evolution. He reached the islands in 1835 during the second voyage of HMS Beagle and stayed for about five weeks.

Darwin observed that animals on different islands could resemble one another while also showing distinct features. Galápagos tortoises, mockingbirds, and finches became especially associated with his evolutionary studies. Differences between island populations suggested that geographic isolation and local environments could influence how species changed over time.

The popular story that Darwin immediately invented natural selection after seeing finches is too simple. His Galápagos observations were important, but he continued collecting evidence and developing the theory after returning to Britain. He later recognized the significance of island variation more fully, with help from specimens and expert comparisons. The islands did not single-handedly prove evolution, but they provided a powerful example of diversification and adaptation. The Canary Islands and Falkland Islands were also visited during his voyage, but they are not the canonical answer to this question.