Darwin's Theory and Turtles

Charles Darwin was an English naturalist who travelled thousands of miles to obtain factual evidence to support the theory of evolution. According to Charles Darwin animals with variations better suited to their environment would have a better chance of survival and ability to breed. They would then pass on the favourable characteristics to their offspring.

Darwin went on a journey in September 1835 and reached the Galapagos Islands. This was when Darwin made an extremely interesting observation. He discovered that the animals on the Galapagos Islands were not quite like the animals he had seen in South America. In some ways the lizards were the same as those in South America but were different in others. Darwin also observed this to be the same with the many different types of finches on the islands. They were different from the finches he had seen in South America. Darwin then found out something even more important. A tortoise or finch on one island was not quite like a tortoise or a finch on another island. By looking at the shell of a tortoise or the beak of a finch you could tell which island it had come from. All the finches had dull colored feathers and short tails. They all laid four pink and white eggs in nests with small roofs. The difference was they all had different beaks. On one island they had strong thick beaks for cracking open nuts and seeds. On another island eighty kilometres away they had long thin beaks for catching insects.

There are about 250 species of turtles and tortoises, ranging from the tiny three-inch bog turtle of eastern North America to the seven-foot-long, one-ton leatherback sea turtle of the Atlantic and Pacific oceans. There are freshwater turtles, sea turtles who live in oceans, and tortoises—turtles that live on land.
All turtles have shells and scaly skin, but each species has special characteristics to live in its environment, such as webbed feet for swimming, long claws for digging, or a flattened shell to hide from predators in rock crevices.

Let's take a couple looks at some different turtles and their characteristics:

SNAKENECK TURTLE

The common snakeback turtle has powerful webbed feet for swimming, digging, and tearing apart prey. Its carapace (shell) is flattened, broad, and brown with black-edged scutes.

RED FOOTED TORTOISE
Also known as the South American Red-footed tortoise, the male grows up to 13.5 inches and are somewhat larger than females, which average 11.25 inches in length. It has several yellow head scales and a horizontal bar behind its eye. The carapace (shell top) is black with a small, distinct, yellow area around the areola on each.

In conclusion, turtles and tortoises have different characteristics and each characteristic makes them adjust to their environment. The types of shells, or legs or even the types of necks and mouths makes you know what environment they are living in, including if they are living in land or water environments.

REFERENCED WEBSITES:
http://www.hsus.org/wildlife/a_closer_look_at_wildlife/turtles_and_tortoises/
http://www.zephyrus.co.uk/charlesdarwin.html
http://www.honoluluzoo.org/red-footed_tortoise.htm

REFERENCED PICTURES WEBSITES:
http://www.dkimages.com/discover/previews/937/50336265.JPG
http://www.monsterreef.com/images/REPTILES/TURTLESTORTOISES/TortoiseTEST.jpg