September, 4th, 2018
Moisés Vivas Luna
Galapagos Islands are an archipelago of volcanic islands distributed on either side of the equator in the Pacific Ocean surrounding the centre of the Western Hemisphere, These characteristics create an entire environment with too many forms of life unique in the world.
The islands are known for their vast number of endemic species; Galapagos Tortoise and Galapagos Iguanas are the most unique and famous animals from this region, however, there are a whole variety of unique animal species as well as plants (even aquatic ones).
Although the islands are located on the equator, the Humboldt Current brings cold water to them, causing frequent drizzles during most of the year. The weather is periodically influenced by the El Niño events, which occur about every 3 to 7 years and are characterized by warm sea surface temperatures, a rise in sea level, greater wave action, and a depletion of nutrients in the water.
Galapagos Islands, where Natural Selection Theory was formulated.
Charles Darwin Research Station
Galapagos Islands were studied by Charles Darwin during the second voyage of HMS Beagle (December 1831, October 1836) and his observations and collections contributed to the inception of Darwin's theory of evolution by means of natural selection.
In honor to the importance that Charles Darwin attributed to the Islands to his researches, Charles Darwin Research Station was created, which mission is to provide knowledge and assistance through scientific research and complementary action to ensure the conservation of the environment and biodiversity in the Galapagos Archipelago.
Just northeast of Puerto Ayora is this iconic national-park site, where more than 200 scientists and volunteers are involved with research and conservation efforts, the most well known of which involves a captive breeding program for giant tortoises. Paths leading through arid-zone vegetation take you past tortoise enclosures, where you can get a good look at these Galápagos giants. There's also a baby-tortoise house with incubators (when the tortoises weigh about 1.5kg or are about four years old, they’re repatriated to their home islands).
Galapagos Islands is home to the famous Galapagos Tortoise, Modern Galápagos tortoises can weigh up to 417 kg (919 lb) and reach 6 feet in length.
Baby tortoises hatch after four to eight months in the egg. They are extremely small and vulnerable when they first hatch, weighing as little as 50 grams (1.8 oz) and measuring 6 centimeters (2.4 in). With lifespans in the wild of over 100 years (A captive individual lived at least 170 years), it is one of the longest-lived vertebrates in the world.
These slow-moving animals were easy prey for pirates and colonists who used them for food and money which led to a threatening decline in numbers in the late 1970’s. This is why today great care is taken to ensure the Galapagos Tortoises bring their numbers back up. The hatcheries help make sure the tortoises get to a big enough size to where they have a better chance of surviving once released back to the island.
The tortoise size and shell shape varies depending on where they live. The shell is made of bone and is a dull brown color. Their ribs, backbone and breastbone have become part of the shell which is why you can never separate the tortoise from its shell. The only natural predator of the Galapagos tortoise is the Galapagos hawk. The hawk preys on the eggs and the newly hatched tortoises.
If a fight breaks out between males, the tortoises face each other, open their mouth and stretch their head as high as they can. Whoever reaches the highest wins. Occasionally they will bite at each other, but usually the shorter male will turn and run away or pull his head into his shell with a hissing sound, ending the battle. These fights usually occur over mates or food and are serious events for the tortoises.
Lonesome George is the most famous tortoise of them all! He became the face of the Galapagos Islands and an icon for conservation. After the drastic decline in subspecies, Lonesome George was the only known living individual from his specific subspecies until his recent death in 2012. The loss of any subspecies is seen as a tragedy by biologist and the general public and Lonesome George will definitely be missed!
Other Curious Facts about Galapagos Islands
Although Galapagos Tortoises are the most famous animals in the islands, at the Charles Darwin Research Station, you also get to see the Galapagos Land Iguana. Also known as the sea iguana, saltwater iguana, or Galápagos marine iguana, is a species of iguana found only on the Galápagos Islands that has the ability, unique among modern lizards, to forage in the sea, making it a marine reptile. This iguana feeds almost exclusively on algae and large males dive to find this food source, while females and smaller males feed during low tide in the intertidal zone. They mainly live in colonies on rocky shores where they warm after visiting the relatively cold water or intertidal zone, but can also be seen in marshes, mangrove and beaches.
Wild dogs that were brought to the island almost killed a colony of over 500 land iguanas in 1970’s. The Research Station was able to rescue 60 survivors and in an effort to re-build their population, they began a breeding program for iguanas in Santa Cruz. This breeding program is still active today!
Many of the species that call this islands home, are found nowhere else in the world, this is what makes Galapagos so magical, even today it seems like the islands are really isolated from human impact. This is undoubtedly a unique spot in the globe which counts also with a great significance for the history of science and therefore for our progress in the understanding of life.