These facts have created special and very different conditions to the ones the species came from. The great volcanic activity, the water amazing productivity and variability, and the extreme isolation from any other location pushed the species to change in very specific directions, adapting to this extreme conditions until today.
This process happened rapidly, speaking in terms of biology and evolution due to the absence of resources, which accelerated the process of adaptation of the ones who survived. In fact, the Galapagos is the only place where these processes are to be witnessed and evidenced as evolution. This gives this location its fame. This is where Charles Darwin was inspired to draw up his theory of evolution and the origin of species. The process these species went through is the one known as Natural Selection , the path by which the species change thru time becoming better adapted to the environment and conditions.
In our times, the Galapagos Islands remain one of the most unique, scientifically important, and biologically prominent corners of Earth. This combination of both physical and biological factors has been studied for many scientists and still today cause interest and controversy. The Galapagos are an interesting place for ecologists and biologists because, in limited and small areas like the islands, it is easier to study and understand relationships and dynamics among the populations of species.
Charles Darwin was 22 years old when he visited the Galapagos Islands on September An amateur geologist and had a very interesting curiosity on beetles. His social upbringing granted him a comfortable life and finally the chance of traveling with Captain Fitzroy, aboard the HMS Beagle.
The Beagle was to travel the world for five years in search of geographical, botanical and military data. He attended medical school in Edinburgh, Scotland, the Athens of the North and later, forced by his father, he studied Divinity in Cambridge.
He would always be the first to disembark and the very last to get back on board. This allowed Darwin to really get to know the geology, fauna and flora and all other aspects of each coast and location the Beagle reached, including the Galapagos Islands. Darwin was a keen Naturalist.
He noticed and described about every single detail of the rocks, plants and animals he saw. He hunted, purchased, stuffed and sent back to England many pounds of samples, including fossil rocks and letters to his sisters. By the end of the trip, in , he had written hundreds of pages with ideas and data.
His head was so full of it, that it would take him a quarter of a century to put them together. On his return to England, Darwin engaged into publishing his records and thoughts.
What would not see the light was a crazy idea that he only shared privately with his mentors and scientific friends. Not until Captain Fitzroy on command of the ship had offered Darwin the opportunity to travel in the boat collecting scientific information and species. Most of the specimens he first collected were marine invertebrates and plankton that he picked from the boat. The journey was an educative and scientific experience for Darwin, he had started his studies on Geology and influenced by thoughts from Lyell and others, he started to theorize about all the landscapes and formations he encountered.
The first mission of Captain Fitzroy, when he was 23 years old, was to plot charts of the end tip of South America his charts of the Galapagos were in use until World War II. He transported 23 samples of the newly invented chronometer, an acquisition of the Navy that had the aim of accurately measuring Longitude.
The first location visited was the occidental side of Africa , the archipelago of Cape Verde, there he started his first observations on beaches formation however this visited most shocked him by the slave trade on going on the archipelago. After this, the boat arrived to Brazil, where Darwin had the chance to collect and admire species from the Amazon tropical forest.
In Argentina, Bahia Blanca, he explored big extinct mammals fossils and seashells that lead him to his first endeavor about the mutability of species.
All the evidence he found on his journey was sent back to England to be better studied by experts on each area. The criteria used to analyze and collect info were his tremendous curiosity. He would also observe and examine the human populations and how small differences in the environment would influence on their cultural and social activities. In Chile Darwin witnessed a powerful earthquake that offered him the chance to see the uplifting of the layers.
This, together with more marine evidence he found in the mountains of Peru, lead him to understand that geological movement and uplifting, would result in sinking islands and formation of coral reefs. In Australia and the Cocos Islands, the extreme differences he noticed in between different species, together with the tortoise shells of different shapes, suggested a different theory of the stability and variability of the species, later to be discussed with experts back in England.
Most extinct species found in his journey were directly linked to living species of South America, and them, to some of the subspecies of the Galapagos. These lumbering behemoths, he found, came from all over the island to drink water at several small springs near the summit.
Darwin counted the number of times that the tortoises swallowed in a minute about ten , determined their average speed six yards a minute , and studied their diet and mating habits. While in the highlands Darwin and his companions dined exclusively on tortoise meat. He commented that it was very tasty when roasted in the shell or made into soup.
He was the first geologist to appreciate that such sandstone-like structures, which rise to a height of more than 1, feet, owe their peculiar features to submarine eruptions of lava and mud; they mix at high temperatures with seawater, producing tiny particles that shoot into the air and rain down on the land to form huge cinder cones. The ship spent the next two days completing a survey of the two northernmost islands and then, 36 days after arriving in the archipelago during which he spent 19 days on land , the Beagle sailed for Tahiti.
Although Darwin did not yet fully appreciate it, a revolution in science had begun. To Darwin, such logistics would have been even more problematic, as he did not have the lightweight equipment, such as aluminum-frame backpacks and plastic water containers, that we have today.
Assisted by his servant, Darwin would have brought his geological hammer, a clinometer for measuring inclines, a shotgun for collecting birds, a compass, plant presses, rodent traps, specimen bottles, spirits of wine for preserving invertebrates, a notebook, a sleeping bag, food and, of course, water. Our two guides had suggested a shortcut across a coastal lava flow. As we began our trek across this perilous field of jagged lava, we had no idea how close to death we would all come.
What was supposed to be a 6-hour excursion became a hour nightmare as we climbed over jumbled piles of blocks with razor-sharp edges, and in and out of steep ravines formed by meandering lavas and collapsed lava domes.
During our second day on that Santiago lava flow, our water ran out. To make matters worse, our two guides had failed to bring any water of their own and were drinking ours.
By the afternoon of the third day we were all severely dehydrated and were forced to abandon most of our equipment. In desperation, our guides hacked off a candelabra cactus branch, and we resorted to drinking the juice, which was so bitter that I retched. Before we finally made it to the coast, where a support vessel was frantically looking for us, one member of the expedition was delirious and close to death.
He was subsequently hospitalized for five days, back in the United States, and it took him more than a month to recover. The day was unusually hot, and Tye, after a few hours of hiking, felt the onset of heat exhaustion and asked me to take over the lead. Using a machete to help clear our way through the brush, I too became heat exhausted, and began to vomit. Heat exhaustion turned out to be the least of my problems. I had inadvertently cut the branch of an overhanging manzanillo tree, whose apples are poison to humans but beloved by tortoises.
The sting from the sap was almost unbearable, and dousing my eyes with water did nothing to help. For the next seven hours I was nearly blinded and could open my eyes for only a few seconds at a time. As I walked back to our campsite, five hours away, I often had to balance, with my eyes shut, on huge boulders in a dry riverbed, and on the edge of lava ravines.
Those were the most painful seven hours I have ever spent. Legend has it that Darwin was converted to the theory of evolution, eureka-like, during his visit to the islands.
How could he not have been? It did not anchor at any of these islands and instead decided to head for James Santiago Island, as they were running low on fresh water. The Beagle found no water on James and headed back to Chatham to resupply.
They collected many specimens, including:. It was about this time that Darwin realized that the different islands were home to different species.
Fast fact: Darwin never set foot on Culpepper, the Island that now bears his name. Tour the Islands like Darwin. Although he was only in the Galapagos for five weeks in , it was the wildlife that he saw there that inspired him to develop his Theory of Evolution.
In chapter two of The Origin of Species, Darwin claims that it was his visit to the Galapagos that helped inspire his theories. The Galapagos Archipelago was key for him to prove his point:. In other words, the endemic species that had evolved on remote islands proved his point as they adapted over long periods of time to a new environment, leaving behind their original characteristics.
His earlier journal, Voyage of the Beagle, however, shows the crucial role these finches played in his theories. He stated:. Gould has divided into four subgroups. All these species are peculiar to this archipelago; and so is the whole group, with the exception of one species of the sub-group Cactornis, lately brought from Bow Island, in the Low Archipelago. You can follow in the steps of Darwin via cruise , personalized island-hopping , or a combination of both.
Galapagos Islands.
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