For a long time the islands of enchantment as they were known to some, were not to be found on maps anywhere. But once these islands - 600 miles from the South American coast - appeared as a few incidental blotches on maps, they began to have a greater and greater impact on human beings. Why? Because the life forms here, even the same creatures on neighboring islands looked different, and were so strange and unique that visitors found themselves asking the crucial question: why is life here so different to anywhere else?
Indeed, on Galapagos you will find enormous creatures, like two distinct species of tortoise, and birds like the Galapagos Albatross and frigates. There are other creatures not found anywhere else on earth, like the Galápagon land iguanas, flightless cormorants and blue footed boobies*. The tortoises are giants, one has a unique saddle shaped shell that allows for high neck stretching (these tortoises feed on cactus flowers for example). And it is from these animals, that the islands - many with the same shape and volcanic design - get their name.
It is interesting to see what specialised skills various creatures have developed. Lizards that became marooned on these isolated islands developed the ability to swim in the sea, and feed on seaweed. A species of Finch diversified to fill the niches that would normally be held by many other bird species. So one species of Finch developed a different sized beak - longer, shorter, or thicker. One of these even developed the ability to use tools, cutting twigs to the appropriate size and then lancing grubs inside hard branches.
All these adaptations only came about after plenty of failures, plenty of deaths in a harsh environment. Amazingly, when Darwin visited Galapagos in September and October of 1835 (for just 5 weeks) he missed most of these vital clues. He collected the finches but did not guess they were the same species. He heard about the different tortoises, but only saw the non-saddle-shaped shell species himself. But he did capture a mockingbird, and remembered the same species in South America. And so he asked himself: how come this species, almost identical, has a slightly smaller body and shorter beak on these islands?
Looking at the volcanic structure of the islands, Darwin gradually came to an epiphany. He realised he was looking back through time, to the beginning of life on Earth. He saw that different environments cause life to change to suit these environments. Thus he saw that life adapts to an environment, and these adaptations lead to evolutionary changes.
The strange diversity on this archipelago started, though, with the Mockingbird. These birds that looked so different elsewhere elicited a response from Darwin. The irony then is equally strange: Darwin started on his intuitive journey thanks to mockingbirds, or mocking-thrushes as Darwin referred to them. These birds are fierce defenders of territory, and demonstrate the talent to innovate by, for example, mimicking the songs of other birds. It is appropriate, in my opinion, that mankind, so ignorant for so long of the true state of Nature, should discover it through the Mockingbird;-)
Galapagos, narrated by Tilda Swinton concludes in South Africa next week at 10pm, on SABC 2. Don't miss it.
*Boobies are also found along the Pacific West Coast as far up as Mexico, but are particularly visible at Galapagos.
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