Charles Darwin

"When on board HMS Beagle as a naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species - that mystery of mysteries, as it has been called by one of our greatest philosophers." Charles Darwin, 1859

Introduction

Charles Darwin

The most celebrated visitor to Galapagos was undoubtedly the young Charles Darwin in 1835 on board HMS Beagle, commanded by Captain Robert FitzRoy. The ship was homeward bound after spending 3 years charting the coasts of South America from the Rio Plata round to Chiloe in southern Chile. In his travels ashore on the pampas of Argentina and in the Cordilleras of the Andes, collecting animals and fossils and studying the geology, Darwin had been exposed to a wider range of phenomena than any previous scientist. His innate qualities of enquiring critically with an open mind into the whys and wherefores of every one of his observations had given rise to doubts in his mind about the correctness of the view of the Creation held at that time by most scientists as well as the Church, maintaining that all species were fixed and unchanging. In the Galapagos he found a remarkable population of plants, birds and reptiles that had developed in isolation from the mainland, but often differed on almost identical islands next door to one another, and whose characteristics he could only explain by a gradual transformation of the various species.

On the Origin of Species

Soon after his return to England in 1836, he arrived at the principle of 'natural selection' as a mechanism for the creation of new species, but for the next 20 years he kept his ideas strictly to himself, Charles Lyell, and Joseph Hooker, while he patiently amassed evidence in their support. On 1 July 1858, in response to a letter from Alfred Russel Wallace who had come up with a virtually identical theory, though with less supporting evidence, the joint Darwin-Wallace papers were presented in outline to the Linnean Society of London. Darwin then settled down to write a fuller account of his theory, and On the Origin of Species was released to the booksellers on 24 November 1859. Although his ideas were soon accepted by the majority of scientists, the challenge that they offered to the Church and to the rest of society took longer to make its mark, but their importance in obliging Mankind to take a radically fresh view of itself has long since been universally recognised.

Captain Fitzroy of the Beagle

The events that led to Darwin's recruitment to sail on HMS Beagle were somewhat bizarre. When in 1830 Captain FitzRoy was commanding the ship on the first of her two survey voyages, he had trouble in Tierra del Fuego because of the tendency of the local people to steal everything on which they could lay their hands. He tried to curb their thieving by taking some hostages, but they preferred retention of their booty to the release of their comrades. He was left with four Fuegians on his hands, and conceived the notion of taking them back to England to be educated, and later returning them to Tierra del Fuego to pass on the benefits of civilisation to their people. The Lords Commissioners of the Admiralty were not very sympathetic with his philanthropic proposals, but eventually succumbed to pressure from his influential relatives, and re-appointed him to the command of the ship in 1831 so that he could both complete the survey and repatriate his Fuegians. Fitzroy had recorded in 1830 that if he went out again, he would like to have a geologist with him to examine the land while he and his officers looked after the hydrography. So he asked his friends at Cambridge University to suggest a suitable person for this post, and they came up with the name of Charles Darwin, who had just graduated in theology, but was considered to have much promise both in geology and in natural history. After Charles' father had been persuaded that the trip would not be unsuitable to his chosen profession as a clergyman, he was interviewed by FitzRoy and accepted as his companion to serve as the Beagle's geologist and naturalist.

Darwin in Galapagos

At last on the way back to England after repatriating the Fuegians, and devoting 3 years to FitzRoy's survey of the coasts of Argentina and Chile, the Beagle arrived in the Galapagos Islands on 15 September 1835. The next day, Darwin landed on the western end of Chatham Island, now known as San Cristobal. He was not very favourably impressed by its appearance, and wrote in his diary; 'The black rocks heated by the rays of the vertical sun like a stove, give to the air a close & sultry feeling. The plants also smell unpleasantly. The country was compared to what we might imagine the cultivated parts of the Infernal regions to be.' The marine iguanas that were common along the shores of all the islands were 'hideous-looking creatures, of a dirty black colour, stupid and sluggish in their movements', but in the water they swam 'with perfect ease and swiftness'. He soon found how extraordinarily tame the birds were, and recorded that 'I pushed off a branch with the end of my gun, a large hawk'.

The giant tortoises

Galapagos Giant Tortoises Darwin's opinion of the fauna rose further when he met his first giant tortoises, striding along 'broad and well beaten tracks' to drink at their watering places. When on 24 September the Beagle moved on to Charles Island (now known as Floreana), he met the English Governor, Nicholas Lawson, who claimed that he could 'pronounce with certainty from which island any tortoise had been brought' from the shape of its shell. However, the possible implications of this remark did not strike Darwin until later, and he failed to collect any of the tortoise carapaces in the islands he visited. Like everyone else at that time, the crew of the Beagle regarded the tortoises simply as an inexhaustible source of food, and some 50 tortoises were captured by hunting parties on San Cristobal Island. But they were all eaten during the journey home and the shells were not preserved for science.

The final land visits

Next they visited Albemarle (Isabela) Island, where Darwin first saw land iguanas, which 'are hideous animals, but are considered good food.' On 8 October, Darwin was left with a small party on James Island (Santiago) where they camped at Buccaneer Cove for nine days, explored the highlands, saw many tortoises, and collected a variety of birds. On 18 October, having completed the survey of Isabela, the Beagle picked up some members of the crew who had been surveying Abingdon (Pinta) Island, and sailed away northwards past Culpepper and Wenman Islands, bound for Tahiti. HMS Beagle had spent just five weeks in Galapagos waters, but Darwin's presence on board ensured that Galapagos would occupy a special place in the history of science.

The role of Galapagos

Darwin Finches In the opening sentence of On the Origin of Species, Darwin affirmed that his observations when on board HMS Beagle had played a vital part in the development of his theories. However, the idea that he was struck by a blinding flash of inspiration on first landing in Galapagos and seeing the finches that came to bear his name is far from the truth. It is clear from his notes that he continued for some nine months after visiting Galapagos to believe in the fixity of species and his earliest doubts about the correctness of this doctrine, written around 1 July 1836 on the last leg of the journey, were based on the mockingbirds that he had collected, not the finches. It was only in March 1837 that the penny dropped, when the ornithologist John Gould reported to him that the finches were not, as he had supposed, members of several widely different families, but all belonged to one remarkable new family now known as the Geospizinae. It then became clear that Darwin had mixed up some of his specimens, and had not recorded with his usual care exactly where all of them had been collected, so that he was obliged to seek help from those of his shipmates who had also shot some finches. The resulting collection, now lodged at the Natural History Museum in London, has been described as a taxonomist's nightmare. Nevertheless, the manner in which members of this family of birds had evolved to fill several distinctly different ecological niches has been fully confirmed by later workers, and recent studies in Galapagos on the beaks of the finches have provided striking new evidence on the operation of natural selection in real time.

Conservation in Galapagos

The concept of conservation had yet to be born in 1835, and as has been seen, Darwin behaved as all his predecessors did, and departed with a large load of tortoises. But within 10 years the tortoises were extinct on Floreana Island, partly because of heavy depredations by visiting ships, and partly because the tortoises were losing out through competition with the goats that had been introduced, and the destruction of their eggs and young by dogs and rats. He would have been the first to appreciate the vital importance of protecting the fauna and flora from feral competitors if the Enchanted Isles were to remain as he found them.