The Galapagos Islands are a small archipelago of volcanic islands in the Pacific Ocean just west of continental Ecuador. They were home to members of a pre-Incan native people, and their first-known inhabitant was an Irish sailor named Patrick Watkins in the early 19th century. But what the islands are most known for, perhaps, is being the birthplace of Charles Darwin’s scientific theory of evolution by natural selection thanks to the highly specialized species that call the islands home. There are so many facts about the Galapagos Islands that give us insight into the Earth's history – and also give us warnings about what happens when we overhunt animals and destroy natural habitats.
Darwin studied a wide variety of endemic species during his voyages on the Beagle, and, since then, the islands have served as a destination for scientists, adventurers, and animal lovers alike. And for good reason – the climate and habitat of these islands make them one of the most unique and beautiful places in the world. Some of the Galapagos Islands' animals are truly unlike any other.
These colorful lizards are the only extant marine lizard in the entire world. It likely evolved its marine lifestyle because of the nature of its ecosystem, as well as the abundance of food in the surrounding reefs.
The strongest of the species are able dive 30 feet deep to feed on its food of choice, subtidal algae and 4-5 red algal species, but most individuals simply forage during low tide.
The iguanas have evolved specialized nasal glands that allow the sea-faring creatures to filter the salt out of the sea water and expel it from their nostrils – another incredible testament to the evolutionary power of the animal kingdom
Perhaps the most famous of all the Galapagos Islands animals, Darwin’s finches are a group of approximately 14 distinct species of birds, all of which evolved from a common ancestor. The birds were collected by Darwin during his second voyage to the Galapagos, and they were an intrinsic part of the development of his theory of evolution by natural selection.
The reason these birds were such a perfect foundation to build his theory around was because of the fact that, although they shared a common ancestor, they demonstrated clear diversity and manifested specific adaptations that applied to the particular island they called home. The finches adapted to the various food sources that were available to them, with some species subsisting on nuts, others on fruits, and others feeding on insects. The shapes of their beaks reflect their food sources, having adapted to them over time.
At one time, the gentle giants known as the Galapagos tortoises were extremely numerous on the islands. They had such an impact on the Spanish sailors who discovered the islands in 1535 that they named the islands after them; the word “galapago” means “tortoise” in Spanish.
These tortoises are the largest of their kind in the world, and, while scientists debate whether or not the different populations are separate species or just sub-species, they are all impressive. For example, the Chelonoidis elephantopus (which until recently was thought to be extinct) has been known to weigh almost 900 pounds.
The size isn't their only impressive characteristic; the Galapagos tortoises are among the longest-living vertebrates in the world, and they can live up to the ripe old age of 170.
The tortoises were the kings of the Galapagos at one time with a population estimated to exceed 250,000 individuals in the 19th century. Now, approximately 19,000 remain. Luckily, thanks to passionate conservation efforts, the population seems to be on the rebound.
Large islands are often home to birds that have lost the ability to fly – instead using their wings to navigate the surrounding waters to feed – but what makes the cormorant so incredible is that it is the only animal of its genus (Phalacrocoracidae) in the entire world that has lost its ability to fly. As a result, the bird is the largest cormorant species in the world.
In addition, the flightless cormorant is only found on Fernandina Island and Isabela Island. While the species once thrived before invasive species were introduced to the islands, new predators such as cats and rats now prey on the bird, which has caused the population to dwindle down to around 1,000 breeding pairs.