Charles Darwin in Cape Verde
Charles Darwin is best known for his theories about natural selection and the evolution of species and his trip to the Galapagos Islands, but what many may not know is that Darwin was also a geologist and visited Santiago (which he then called St. Jogo) in Cape Verde on January 16, 1832 in his “Beagle” expedition. Cape Verde was not planned as a destination for the expedition, but rather it was improvised after the captain was unable to gain access to Tenerife in the Canary Islands. Darwin had been looking forward to exploring the well talked about Canary Islands and arrived in Santiago with very low expectations, having heard of the ugly port of Praia which was well known for its use in the slave trade. He was not impressed with the city of Praia and at first commented on the bareness of the landscape, however he soon began to change his mind as he basked in the tropical climate, very different from what he was used to in England. In Darwin’s book The Voyage of the Beagle 1839, he writes:
“The island would generally be considered as very uninteresting, but to anyone accustomed only to an English landscape, the novel aspect of an utterly sterile land possesses a grandeur which more vegetation might spoil. A single green leaf can scarcely be discovered over wide tracts of the lava plains; yet flocks of goats, together with a few cows, contrive to exist. It rains very seldom, but during a short portion of the year heavy torrents fall, and immediately afterwards a light vegetation springs out of every crevice. This soon withers; and upon such naturally formed hay the animals live”.
The landscape was not what stole his heart of course. As a budding geologist he was captivated by the geological structure of the island. Although he described it as simple, it challenged the popular belief of geologists of his time that assumed that geological processes of the past had occurred rapidly and differed from the slow working processes of the present. Geologist Charles Lyell disagreed however, arguing that the processes that were slowly shaping the earth in their time were the same that had acted throughout history and therefore believed in a much longer earth history than was common. At the time Darwin had believed that the earth was not much older than 6000 years old, having commented in his book that a Baobob tree he encountered, that was estimated to be around 6000 years old, would have lived through a significant part of earth’s history. After studying the volcanic rock formations of Santiago and the fossils found in the bicarbonate layers, especially of the small island of Santa Maria, Darwin concluded that the earth must be much older than he previously thought and he converted to a believer of Lyell’s theories of geology.
The fossils that he found closely resembled the organisms living in the shores which he wanted to explain as being deposited recently, however given the composition of the layers of the island it would have been impossible. The only possible explanation was that the structure of the volcanic rock valleys of Santiago could only have been formed by the slow working force of erosion. With that idea, the fossils he found also hinted at how slowly the evolution of species occurs. Having found ancestrial creatures that so closely resembled those of his time could only mean that big evolutionary changes, like the separation of a single species in to sub-species’ or the evolution of a new species, would take an incredibly long time to occur. As many know, Darwin further studied this theory later in the Galapagos, publishing his most famous book, The Origin of Species. Cape Verde is an archipelago that is rich in culture and history that has played a big role in creating the world as we know it.