By Andrea Reategui
Approximately 600 miles off the coast of Ecuador exists a chain of islands known as the Galapagos, from their original name of Insulae de los Galopegos, (Islands of the tortoises).
These islands present a treasure chest of evolutionary information for scientists. There are 13 volcanic islands, and each has its own variation of endemic species, some similar to species on other islands, but each unique. Charles Darwin took notice of this detail. Charles Darwin developed his theory of evolution by natural selection after he visited this unique archipelago. Simply put, the variations of characteristics in a population of any species is dominated by the characteristics that best adapts to the environment. Because the environment is subject to change, dominating phenotypes, or genetically passed traits, may shift accordingly.
For example, finches seen in the Galapagos have beaks that vary in size. Each finch specializes in eating different types of seeds, something that allows them to coexist. When trees with big seeds are flourishing, finches with large beaks are the most abundant, and finches with medium and small beaks are less abundant. As the seasons shift and trees with smaller seeds begin to flourish, the dominant phenotype shifts to the small-beaked finch, and the finches with large beaks become less abundant. Another example could be seen in the tortoises. Tortoises that feed on higher vegetation have saddle-shaped shells allowing them to reach the higher vegetation. These tortoises would not be able to inhabit the same niche as those which feed on lower vegetation and have dome shaped shells. The saddle shaped shells would be unable to maneuver through the habitat because their shells would get caught on the branches of the underbrush.
The multitude of different tortoises is only the beginning. The wildlife found in the Galapagos is astonishing. One can find a variety of boobys, frigate birds and the famous Darwinian finches. Visitors can approach the iguanas, tortoises, and seals like they can no where else. This may be in part because of the lack of human contact these animals have had or because strict national park regulations that prohibit humans from hunting or otherwise disturbing the animals. The large variety of marine life is a result of a cold upwelling that brings nutrients to the coastal environments of the islands. The animals roaming the waters range from baleen and toothed whales to roughly 750 species of fish, of which about 17 percent are endemic to the Galapagos. This amazing assortment of wild life is part of one the most pristine ecosystems found today.
The Galapagos Islands were established as a National Park by the president of Ecuador. It was a big step in terms of conservation, and one which might help to keep the remaining 95 percent of the archipelago’s species intact. However, the increasing tourism is becoming a gateway for invasive species.
Cruise ships full of tourists can bring larvae of new species in their ballast tanks. Ferries and other boats that come from the mainland bring roaches and rats. Inhabitants bring cats and dogs which get loose and prey on native birds and other animals throughout the islands. As tourism increases so does the need for more diesel, drinking water, and food. If tourism continues to increase, the ecosystems may fall victim to pollution and all the invasive species that get brought over.
The islands play an important role to help widen views on sustainable development and conservations methods that can be applied in other parts of the world. Overall, the Galapagos Islands are a treasure for the world to behold and learn from.
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