Weighing in at over 600 pounds and living more than 150 years is the largest and oldest living tortoise, the Giant Tortoise of the Galapagos Islands. At one time, this large tortoise had 13 subspecies, but due to extinction, there are only 11 subspecies of the Giant Tortoise alive in the wild.
The Galapagos Islands are of volcanic origin and rose from the sea after a large amount of volcanic activity millions of years ago and is now one of the most popular resting places for 11 species of Giant Tortoises, approximately around 15,000.
These Giant Tortoises are big, with their large shells made entirely of bone, which are fused with their ribs and other bones to form this protective layer. This large shell is their main source of protection, whenever threatened by a predator, like all turtles, they would retract their legs and head into their shell for protection. The Giant Tortoise even has protective heavy scales on its legs to help against a predator's attack, if by chance the tortoise isn't fast enough to retreat into his shell.
Giant Tortoises are one of many animals that bask in the sun and absorb its energy. Because they are cold blooded animals, they spend two to three hours after sunrise to soak in all the sun's energy through their shells to energize themselves and become very active for about nine hours a day. However, due to their size, they tend to be very slow and tend to walk only about 0.18 mph. During the daylight hours, the Giant Tortoise will feed on grass, leaves, fruit, as well as the poisonous apple, which is deadly to humans but a favorite by the Giant Tortoise.
All of this activity for such a large animal can normally result in them to sleep for about 16 hours each day in depressions in the ground created by the tortoises, or wallowing in a pool.
Of the remaining 11 species of Giant Tortoises, all of them fall into one of three types of categories based on their shells and their location on the Galapagos Islands. The first is the Saddle-Backed. This tortoise is mostly found on the lower, drier islands and their necks and legs are longer, and their shells are raised off of their bodies. Second is the Dome-Shaped, this tortoise type is found on the upper parts of the Galapagos Islands and normally hide out where there is a lot of thick plan growth. Their shells are round and their necks and legs are fairly short. The last is the Intermediate which is a mix between the Dome-Shaped and the Saddle-Backed.
The species that has been getting the most attention of all of the Giant Tortoise species is that of the Pinta Tortoise. Lonesome George is his name, yes that's right, there is one lonely Pinta Tortoise left in the entire world, and his name is Lonesome George. He was found in 1971 on Pinta Island in the Galapagos and is predicted to be about 90 years old. Lonesome George is currently being held in captivity with two female Giant Tortoises whose species resemble that of the Pinta Tortoise. The researchers are trying to create some sort of breeding program to hopefully carry on at least part of the Pinta Tortoise species. However, it seems like old Lonesome George may have grown up alone and never learned proper social or mating skills because he hasn't had much luck with the ladies. Sadly enough, when Lonesome George passes away, the Pinta Giant Tortoise species will be extinct.
The main cause of extinction has been blamed on humans. In the past there were a huge population of Giant Tortoises that fell victim to being hunted by whalers and sealers in the 19th century, as well as fishermen releasing goats onto the Islands during the 1950's which destroyed all the vegetation and causing the Giant Tortoise to compete for their food and survival.
Just this past May, the Giant Tortoises fell victim to another threat when one of the largest volcanoes on the Galapagos Islands erupted. Cerro Azul Volcano erupted full force, throwing lava down the side of the mountain and into a large area where was considered to be largely populated with the Giant Tortoises. The Galapagos Island governor states that once the lava flow stops, they are going to try to airlift the tortoises out of the area.
In conclusion, the Galapagos Giant Tortoise is a species that is not going to go away without a fight, and it seems as though many researchers and scientists are doing their best to preserve the life and assist in the mating process of these large tortoises to keep their place in the circle of life.