Charles Darwin was an English naturalist who is most well known as a collector and geologist. He came up with scientific information that all species of life have evolved over time from similar ancestry through the process of natural selection. The scientific community embraced Darwin’s theory and natural selection became the primary basis of evolution in the early 1930s and is still the basis of modern evolutionary theory today. (Charles Darwin, 2008)
Darwin is significantly known for his voyage on the Beagle, where he sailed around various parts of the world. He traveled for 5 years collecting fossils, information and data on many different species. Some consider his most well-known finding to be the tortoise. While on the Galapagos Islands, Darwin learned from local inhabitants that a tortoise can be identified by its appearance. Darwin believed Spaniards claimed they could tell where the tortoises originated by their physical characteristics. (Charles Darwin, 2008)
The tortoise is considered by many to be the most recognized symbol of the Galapagos Islands. The tortoises currently found on the Galapagos are the largest in the world, weighing up to 500 lbs., with a life span of nearly 150 years. The feature of the shell is made up of the rib cage, collar bone and pelvis. The ancestors of the turtle were so successful with this form of living that there has been little morphology in over 200 years. Amazingly one turtle genus from South America has not changed its morphology in over 60 million years. Darwin would consider this to be a result of conservation. Conserving turtles and tortoises are very important because there is an enormous demand for trade amongst them all over the world. The demand is frighteningly high in Asia. (Hall, 2004)
Box turtles typically live to be about 40 years old but sometimes live for 100 years. The female box turtle we observed in class is a Florida native. Her scales were beige dark green and yellow and seemed to be armored. Her shell was dark brown with beige and had 2 hinges under her neck and tail to protect her from predators. The male box turtle is very different from the female box turtle. The male we observed was also a native of Florida. He had red eyes and was very aggressive. He had a wide mouth which was very different from the other male box turtle we observed. The second male box turtle we observed was a native of Texas. His scales were camouflage colors, beige and dark green. His mouth was much pointier than the Florida box turtle. Both males had hinges to protect themselves from predators.(Turtle, 2008)
The Central American Ornate Wood Turtle we observed is a native of places such as Ecuador and Venezuela. The one we observed in class was very colorful with black and orange stripes on its scales. Its shell had a hump and seemed to be hardest one. Its neck seemed to protrude the most as well. It had flat feet and a short tail, which means it is female. is a herbivore feeding on mostly greens. They live near grassy areas, forests and ponds. They also feed on small insects and worms occasionally. They are found in Costa Rica and southern Nicaragua. They are highly aquatic when young, as adults they are land-based. The average lifespan is only 15 years. (Turtle, 2008)
Red-footed tortoises can be found in open grasslands of South America in place such as Ecuador and Venezuela. The red-footed tortoise we observed in class was a baby. It had red scales and a dark green and brown shell. It’s face was flatter than the others. Red footed tortoises have sexual dimorphism; the male has a curved belly which is used to easily mount the female for reproduction. Contrarily, the female’s belly is flat. The male is also larger at the same age as the female. They typically live about 50 years and reach about 10 to 15 inches. (Tortoise, 2008)
The Russian tortoise is a vegetarian which feeds mostly on greens. The Russian tortoise we observed in class was a male and, like its relatives, had a large tail. It had only 4 toes per foot and claws as opposed to webbed feet because it is a land dweller. The tortoise was able to completely retract its head and limbs into its shell. Its shell was domed. Its life span is about 50 years but there have been recorded Russian tortoises living to nearly 100 years old. They reach about 6-8 inches upon adulthood. Russian tortoises can be found in Asia regions. (Tortoise, 2008)
The mud turtle we observed in class was dark green and black. It was very small, only around 2 inches long. Its eyes were far apart and its shell came to a point on top. These webbed feet turtles are usually found in water although they are not very good swimmers. They are known as bottom dwellers. They are typically found around lakes and ponds where there is slow moving water. Although very small, they are usually carnivorous. They grow up to 4 inches. Their lifespan is about 50 year. (Turtle, 2008)
The Yellow footed tortoise we observed was the largest one. Its shell was greenish brown and beige, for camouflage. This female yellow footed tortoise had only 4 toes per foot with very short claws. These tortoises typically live to be 50-60 years old. They are very rarely spotted in the wild because they enjoy the dense forests. They are found in South American regions. (Tortoise, 2008)
“The inhabitants...state that they can distinguish the tortoise from different islands; and that they differ not only in size, but in other characters. Captain Porter has described those from Charles and from the nearest island to it, namely Hood Island, as having their shells in front thick and turned up like a Spanish saddle, whilst the tortoises from James Island are rounder, blacker, and have a better taste when cooked”.-Charles Darwin 1845
Charles Darwin. (2008, April 21). In Wikipedia, The Free Encyclopedia. Retrieved 02:42, April 21, 2008, from http://en.wikipedia.org/w/index.php?title=Charles_Darwin&oldid=208012115
Hall, (2004). Turtles. Retrieved April 22, 2008, Web site: http://eebweb.arizona.edu/courses/Ecol483_583/483Turtlelab2004.doc
Tortoise. (2008, April 22). In Wikipedia, The Free Encyclopedia. Retrieved April 22, 2008, from http://en.wikipedia.org/w/index.php?title=Tortoise&oldid=207876697
Turtle. (2008, April 22). In Wikipedia, The Free Encyclopedia. Retrieved 03:02, April 22, 2008, from http://en.wikipedia.org/w/index.php?title=Turtle&oldid=207903752
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