From Oxford, Pete, and Graham Watkins. Galapagos: Both Sides of the Coin.
Of all the scientists to visit the Galapagos Islands, Charles Darwin has had the single greatest influence. Darwin was born on February 12, 1809, in Shrewsbury, England. In 1831, having studied medicine at Edinburgh and having spent time studying for Holy Orders at Cambridge, with nudging from Professor Henslow, Darwin convinced Captain Robert FitzRoy to let him join him aboard the H. M. S. Beagle as the ship’s naturalist. FitzRoy was taking the Beagle on a charting voyage around South America. On September 15, 1835 on the return route across the Pacific, the Beagle arrived in the Galapagos Islands. Darwin disembarked on San Cristóbal (September 17-22), Floreana (September 24-27), Isabela (September 29-October 2) and Santiago (October 8-17). FitzRoy and his officers developed updated charts of the archipelago, while Darwin collected geological and biological specimens on the islands.
At the time of his visit, Darwin had not yet developed the ideas he presented later; it was only in retrospect that he realized the full significance of the differences among Galapagos species. Noteworthy about his visit were his observations of three different species of Galapagos mockingbirds on different islands and what the acting governor, Englishman Nicholas Lawson, told him about the differences among the giant tortoises from different islands. While in the archipelago, Darwin focused as much on geology as on biology, collecting many geological specimens. Later, when he grasped the significance of the differences among the mockingbirds and tortoises, he resorted to the collections of his crewmates to look for inter-island variations among birds, plants, and other species, having failed to label all the specimens in his own collections, by island.
On the Origin of Species (published in 1859) changed the way we look at and understand the world. The book focused on the transmutations of species and explained, in detail, the mechanism that underlies evolutionary change. In On the Origin of Species, Darwin countered the predominant view of the time by presenting observations on the high number of endemic species found in the islands, the close interrelatedness of these species, and the absence of some groups of species. All of these observations ran contrary to the reasoning behind “Special Creation,” then the dominant explanation of the distribution of species.
Critically, Darwin suggested a highly logical alternative mechanism to explain the distribution and types of species, which he termed “natural selection.” His argument was that if individuals vary with respect to a particular trait and if these variants have a different likelihood of surviving to the next generation, then, in the future, there will be more of those with the variant more likely to survive. In On the Origin of Species, Charles Darwin offered a compelling answer to the outstanding question of biology, which was “how life on earth had evolved.” The book was, as Darwin commented, “one long argument” that stemmed from his five-week visit to the Galapagos Islands and attempted to include all life on earth. On the Origin of Species linked Darwin and Galapagos inextricably and changed the islands forever.