It could take at least two years to clean up the gooey black mess. If the fuel sinks to the ocean bottom, it could smother algae and other sea plants that fish, marine iguanas and birds like to eat. In the 1830s, English naturalist Charles Darwin visited the Gal pagos for several weeks on a ship called the H.M.S. Beagle. Finches that eat cactus flowers have pointed beaks that can avoid thorns. And one type of finch can hold a twig in its beak and poke it into the ground to find insects.
Tortoises also vary from island to island.
Those that live in dry areas where food is hard to find have saddle-shaped shells that let them stick their necks out very far to look for food. Darwin later used what he observed to write his theory of evolution, which tries to explain how living things slowly develop new characteristics in response to their environment. More and more tourists visit every year. Populations of sea cucumbers and lobsters are shrinking because fishermen are catching too many of them. Residents' dogs, cats and goats sometimes attack the wild animals or eat their food.