The Marine Iguana
In 1835, the young naturalist Charles Darwin was aboard the HMS Beagle. Heading home after an exploration that no naturalist had ever experienced the like of, the ship was heading home after a 3 year trip that circled most of South America. Darwin had spent countless days of scientific research, ashore the pampas of Argentina or the Cordilleras of the Andes. Collecting specimens and studying the geology of the area. After the many phenomena his uniquely open mind began to question the strict rules of creation that ruled the minds of most scientists of the day. The idea that everything stayed the same over time seemed to close minded after his close observations of life at work. The most influential to most of his new ideas was his work on the Galapagos. There he had observed that hardly any species stayed the same after being isolated from the mainland, adaption was necessary to survive. After returning to England, Darwin was able to come up with the idea of natural selection, an idea that is now one of the main ideas of environmental science. There is a good chance that without his adventures on the Galapagos, Darwin’s theory would be majorly deterred. In return, he is given much credit for the science of the Galapagos, and there is an immediate connection between them.
The Galapagos Islands
The Galapagos are located 696 miles off the coast of Ecuador, at 0° S 91° W. Their location creates warm temperate conditions brought on by vigorous upwelling (Equatorial Undercurrent) and a moderately cool, warm temperate-subtropical influence (Peru Flow). Ocean temperatures can vary from 0 to 27 degrees centigrade, (in the majority of areas inhabited by the marine iguana colonies, water is frigid.)
The Galapagos are quite volcanically active, with almost all the islands in the region centered around large, cone volcanoes. A more arid zone is found immediately inland from the coastal zone, and is the most widespread formation in the islands. The humid zone emerges above the arid zone through a transition belt in which elements of the two are combined. It is a very damp zone maintained in the dry season by thick, garua fogs which accumulate through most of the night and last well into each day. A fern-grass-sedge zone covers the summit areas of the larger islands where moisture is retained in temporary pools. The ending result is a varying environment that can differ on all islands, as Darwin observed in his trip there. These varied conditions also create difference in the marine iguana family, as colour and shape vary from island to island.
