Galapagos Pre-Trip Readings
Animals of the Galapagos
Six-Hundred miles off the coast of Ecuador, lies the Galapagos Islands, an archipelago of volcanic rocks rising out of the vastness of the Pacific Ocean. In this seemingly inhospitable environment, life has found a way to survive, and the plants and animals that call the Galapagos home even thrive in the different ecological niches they exploit. From giant land tortoises to blue footed boobies, cactuses and herbs, the Galapagos seems like a place of enchantment, left virtually untouched for millennia, allowing speciation and natural selection to take place transforming animals and plants.
Six-Hundred miles off the coast of Ecuador, lies the Galapagos Islands, an archipelago of volcanic rocks rising out of the vastness of the Pacific Ocean. In this seemingly inhospitable environment, life has found a way to survive, and the plants and animals that call the Galapagos home even thrive in the different ecological niches they exploit. From giant land tortoises to blue footed boobies, cactuses and herbs, the Galapagos seems like a place of enchantment, left virtually untouched for millennia, allowing speciation and natural selection to take place transforming animals and plants.
Map of the Galapagos Islands (worldatlas.com)
Animals of the Galapagos are as unique as the islands they inhabit. In fact, differentiation of species has occurred from island to island since each island has its own unique climate that varies in temperature and precipitation, mostly due to the elevation of said island. The animals mentioned in the documentary “Animals of the Galapagos Islands” are a testament to the diversity of life in this hostile environment. This documentary talks about the different species of iguana that call the Galapagos home. The marine iguana for example, is a wonderful instance of an animal that is common elsewhere in the world, but has adapted through thousands of years of evolution to actually swim through the sea, thus becoming a new species. These marine iguanas are found nowhere else in the world. They are cold blooded creatures, so they can only brave the cool waters for about 10 minutes, but they can dive to depths of 9 meters to scrape algae of the rocks. There are also land iguanas that call the Galapagos home, although they do not venture into the cool waters for algae, they would much rather munch on some cactus pears. (Eicher 2014)
There are also many species of Galapagos tortoise on the different islands. These tortoises can weigh up to 600 lbs. They are the largest tortoises in the world and they can go for many months without water, and up to a year without food. That comes in handy when the El Niño years mess around with the climate and subsequently the food supply for many Galapagos creatures. Some have domed shells which limit them to low lying plants and shrubs. Other species have saddle shaped shells which allow them to extend their necks upward to bite into some nice juicy cactus pears or other taller vegetation. All of these adaptations came specifically from evolution due be means of natural selection due to the different compositions of vegetation on each island. (Eicher 2014)
There are also many species of Galapagos tortoise on the different islands. These tortoises can weigh up to 600 lbs. They are the largest tortoises in the world and they can go for many months without water, and up to a year without food. That comes in handy when the El Niño years mess around with the climate and subsequently the food supply for many Galapagos creatures. Some have domed shells which limit them to low lying plants and shrubs. Other species have saddle shaped shells which allow them to extend their necks upward to bite into some nice juicy cactus pears or other taller vegetation. All of these adaptations came specifically from evolution due be means of natural selection due to the different compositions of vegetation on each island. (Eicher 2014)
Animals on the Galapagos were able to survive because they developed these adaptations that allowed them to exploit various niches in the environments of the Islands. This did not happen overnight of course. Instead these adaptations came about through evolution by means of natural selection. A theory which still holds true today. Some of these adaptations due to natural selection can be observed from year to year, most notably in Darwin’s finches. These small brown ground finches seem quite plain when compared to the giant tortoises or colorful crabs, but they are amazing since they demonstrate natural selection quite perfectly. In times when the distributions of available food seeds are on smaller range, due to climate conditions such as precipitation, finches with smaller beaks tend to out compete their larger beaked relatives. This drives the average beak size down in next year’s offspring. Likewise, when the available food seeds are larger in size, finches with stronger larger beaks would be able to consume them, out competing the smaller beaked finches and thus leading to an overall increase in average beak size in next year’s offspring. (Biointeractive 2014)
The island of Daphne major is a small island that has basically been a large scale experiment illustrating the natural selection of finches ever since Darwin had set foot on the island almost two centuries ago. There are still studies being conducted to this day which are incredible. All of these wonderful species and bio diversity make the Galapagos a mecca of eco-tourism. The history of the Galapagos and tourism, along with managing urban growth and the resident population is very tumultuous, it has had its ups and downs just like the Ecuadorian economy, and this is talked about below. (Biointeractive 2014)
The island of Daphne major is a small island that has basically been a large scale experiment illustrating the natural selection of finches ever since Darwin had set foot on the island almost two centuries ago. There are still studies being conducted to this day which are incredible. All of these wonderful species and bio diversity make the Galapagos a mecca of eco-tourism. The history of the Galapagos and tourism, along with managing urban growth and the resident population is very tumultuous, it has had its ups and downs just like the Ecuadorian economy, and this is talked about below. (Biointeractive 2014)
Darwin's Finches (wikipedia.com)
Galapagos and Ecotourism
Ecotourism draws in its patrons by preserving unique and wonderful habitats for people to come in an experience for themselves. The people that partake in ecotourism are generally okay with being a little bit more uncomfortable in terms of their accommodations. They also tend to have a greater respect for the environments they are visiting, and are generally more aligned with efforts to conserve these diverse habitats. Ecotourism is a way to bring in more revenue to the Galapagos. The revenue generated is then used to further promote and fund conservations efforts. Tourism of any kind however has an impact on the islands natural ecology. Population growth continues on the Islands to this day. There has also been a history of locals becoming upset and even violent when new conservation measures are put into effect. (Epler 2007) The amount of tourism dollars draws in unemployed migrants from coastal cities such as Guayaquil and other towns on the mainland. The migrants that move to the Galapagos tend to not have the same amount of respect for the islands. Workers that took up jobs in the sea cucumber fishing industry actually occupied the Charles Darwin Research Center in 1993 to protest the call for a complete ban on this fishery. Since only about 3 percent of the archipelago is used for urban development, the amount of population increase must be carefully watched and also the water resources and food resources are also strained on these islands. It is still evident that tourists that visit the Galapagos islands would much rather enjoy the scenic beauty rather than enter towns and stay in them, but the amount of tourists that dine on the Island cities and also go to city nightlife has been increasing. (Epler 2007) |
Top:"The Galapagos Islands ... responsible tourism?" Source: Rachel Dex http://www.theguardian.com/travel/2007/may/05/saturday.green
Bottom: Galapagos Town (Tod Emko) |
The Origin of Birds
The video the “Origin of Birds” is quite thorough and informative on the evolutionary history of birds. It talks about how birds descended from a specific lineage of dinosaurs, that the T-Rex and raptors were a part of. It presented evidence, in the form of similar bone structures, and intermediate fossil records that showed these dinosaurs with feathers. At the end of the video the narrator says that dinosaurs didn’t go extinct, and that we just call them birds. This was very mind-blowing. It is hard to picture a huge lumbering dinosaur turning into a chicken over evolutionary time, but this video does a great job in explaining the emergence of bird like features in dinosaurs such as hollow bones and feathers. Now every time I go into forest, or when I am walking through the Galapagos Islands watching the blue footed boobies dance and the frigate birds fly, and the penguins swim through the water, I will have a greater amount of respect for these animals since they are the last surviving dinosaurs.(Bioninteractive 2015)
The video the “Origin of Birds” is quite thorough and informative on the evolutionary history of birds. It talks about how birds descended from a specific lineage of dinosaurs, that the T-Rex and raptors were a part of. It presented evidence, in the form of similar bone structures, and intermediate fossil records that showed these dinosaurs with feathers. At the end of the video the narrator says that dinosaurs didn’t go extinct, and that we just call them birds. This was very mind-blowing. It is hard to picture a huge lumbering dinosaur turning into a chicken over evolutionary time, but this video does a great job in explaining the emergence of bird like features in dinosaurs such as hollow bones and feathers. Now every time I go into forest, or when I am walking through the Galapagos Islands watching the blue footed boobies dance and the frigate birds fly, and the penguins swim through the water, I will have a greater amount of respect for these animals since they are the last surviving dinosaurs.(Bioninteractive 2015)
Above: Frigate bird relaxing in the sun (galapagosmap.com)
Sources:
Biointeractive. (2014, August 26). Galapagos Finch Evolution. Retrieved from https://www.youtube.com/watch?v=mcM23M-CCog&feature=youtu.be
Biointeractive. (2015, Febuary 13). The Origin of Birds. Retrieved from https://www.youtube.com/watch?v=z4nuWLd2ivc&feature=youtu.be
Cruz, F., Donlan, C., Campbell, K., Carrion, V. (2005). Conservation action in the Galapagos: feral pig (Sus scrofa) eradication from Santiago Island. Biological Conservation. 121. 473-478
Eicher, B., Mayer, T. (2014, October 2). Animals of The Galapagos Islands. Retrieved from https://www.youtube.com/watch? v=5_oN570Kjxs&feature=youtu.be&list=PLyOVSbari5z8dF-o3H7aY8PJpPwLesLOT
Galapagos Conservancy. (2015). Retrieved from http://www.galapagos.org/
Biointeractive. (2014, August 26). Galapagos Finch Evolution. Retrieved from https://www.youtube.com/watch?v=mcM23M-CCog&feature=youtu.be
Biointeractive. (2015, Febuary 13). The Origin of Birds. Retrieved from https://www.youtube.com/watch?v=z4nuWLd2ivc&feature=youtu.be
Cruz, F., Donlan, C., Campbell, K., Carrion, V. (2005). Conservation action in the Galapagos: feral pig (Sus scrofa) eradication from Santiago Island. Biological Conservation. 121. 473-478
Eicher, B., Mayer, T. (2014, October 2). Animals of The Galapagos Islands. Retrieved from https://www.youtube.com/watch? v=5_oN570Kjxs&feature=youtu.be&list=PLyOVSbari5z8dF-o3H7aY8PJpPwLesLOT
Galapagos Conservancy. (2015). Retrieved from http://www.galapagos.org/