To understand how mankind and other organisms came into being and explain the great varieties of species that have and now populate our planet, mankind through the science of archaeology, biology, paleontology and scientific observation have created a theory to explain this journey. This explanation is now known as the Theory of Evolution, the author of which was Charles Darwin. Those who support this point of view are often called Evolutionists.In 1859 he published "On the Origin of Species" and by the 1930's further advanced his view that all living organisms through Natural Selection, change and evolve over generations. In this Theory of Natural Selection each generation adapts and changes to survive and meet the challenges of its environment.
Turtles share a common ancestor. They come from the order of "Testudines" and like humans and other life forms have evolved over generations. In the United States the word turtle is usually used to describe all freshwater and certain land-dwelling species. Those that live in the seas are referred to as sea turtles. A tortoise is restricted to land and a terrapin lives in brackish, swampy waters.
Let us now examine six species of turtles to see how they differ having evolved to their present state as they continue to evolve and adapt to survive in their environment.
Soft Shell Turtles
Found in Eastern United States of America, this soft shell turtle wears no armour. Its shell is mostly comprised of leathery skin covering. Unlike other species, this shell offers no real protection from most predators. If undisturbed it may grow to approximately 38 centimeters or 15 inches in length.
The Soft Shell Turtle must rely on its aquatic maneuverability and speed which it gets from it sleek profile which gives it the ability to lay flat in lakes and rivers and strong hind legs which help to propel it through the water from danger or in search of habitat and food.
Scientific classification: The pitted-shell turtle is a member of the family Carettochelyidae and is classified as Carettochelys insculpta. The spiny soft-shell turtle is a member of the family Trionychidae and is classified as Apalone spinifera.
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Snake Neck Turtles
Chelodina longicollis, also commonly known as the Eastern long-neck turtle, Eastern snake-neck turtle, or Common long-neck turtle has acquired its name from its appearance. One of its major characteristics is that unlike other turtles that pull their heads into their shells, the snake neck bends its neck sometime in a "s" formation as it retracts into its shell for protection.
The common snake neck turtle also has powerful webbed feet for swimming, digging, and tearing apart prey. Its carapace (shell) is flattened, broad, and brown with black-edged scutes. On the underside plates (plastron) there are distinctive black lines or seams.
Two common snake-neck turtles climbing from a lake to bask on a log These turtles are found in the inland slow-moving freshwater habitats such as swamps, dams, and lakes of eastern Australia, from northern Queensland to Victoria. They prefer a soft, sandy bottom and will bask on logs or rocks during the day.
When it feels threatened, this turtle will emit an offensive smelling fluid from its musk glands. This trait gives the turtle one of its other common names, "stinker." The common snake-neck turtle is carnivorous, eating a variety of animals. They feed on insects, worms, tadpoles, frogs small fish, crustaceans and mollusks.
In early summer, the female will lay between 2 and 10 eggs in the banks of her aquatic habitat. Three to five months later the hatchlings break out of their shells. These young turtles often fall prey to predators such as fish and birds. Females will lay 1 to 3 clutches of eggs per year.
Extracted from Wikipedia, the Free online encyclopedia
http://en.wikipedia.org/wiki/Common_snakeneck_turtle
Box Turtles (genus Terrapene) can be distinguished from other native Texas
turtles by having a single hinge at the front of the lower shell (plastron), allowing them to fold it up and closing the front of the shell entirely; thus the common name of "box turtle." Box turtles also have a hooked upper jaw ("beak") that is lacking in other Texas turtles.
The only other land turtle in Texas is the Texas Tortoise; it lacks any hinges on the plastron, has a head entirely covered with scales rather than having skin, and has a very rough upper shell (carapace).
Male box turtles have red eyes (females yellow or golden), a longer tail with a thick base (females shorter and thinner), and a somewhat concave plastron (females have a flat one).
Extracted from the Texas Park and Wild Life website: http://www.tpwd.state.tx.us/learning/texas_nature_trackers/box_turtle_survey/
Central American Ornate Wood Turtle (Rhinoclemmys pulcherrima manni)
The Ornate Wood Turtle, is one of the most common wood turtles seen in the pet trade. They have been imported in large numbers in recent years. They can be quite beautiful and brightly colored, especially those from northern Costa Rica. These specimens will be covered with swirls of orange and yellow along with black ocelli (eyespots). Due to their variety of form along with beautiful colors and patterning, these and all the wood turtles are likely candidates for captive breeding programs.
The Central American Wood Turtles are an appealing group of turtles. They are great to keep and will soon become tame. They are a manageable size for most keepers and have proven to be extremely hardy once established.
Wanderers on land and somewhat shy, they should be offered plenty of shelter in the form of cork bark tubes or piles of dry leaves. They will often race under a shelter at the approach of their keeper, then will cautiously reappear to see if any food has been offered.
Extracted from the website of Animal World http://animal-world.com/encyclo/reptiles/turtles/OrnateWoodTurtle.php
Mud Turtles (Kinosternon subrubrum)
Mating begins in March. Females lay two-five eggs in June, in a 12 cm deep nest that they cover with dirt. They may also lay eggs under logs. The eggs are oval, and are a pink or bluish white color.This species is most active April through October. It may often be seen moving around on the bottom of streams, and is often seen crossing roads. If the stream dries up where they are, they may cover themselves in mud and may wait out the summer in a dormant state, or move to a more permanent body of water. The common mud turtle primarily eats insects, crawfish, seeds, and mollusks.
hell) of the Red-footed Tortoise is dark brown to black with lighter patches in the centers of the scutes and around the edges, usually a yellowish tan or red color. The plastron (bottom shell) is a bland yellowish brown, sometimes with a hint of red. A few or sometimes many of the scales on the front legs, as well as patches on the head are orange, yellow, or red.Due to the large natural range they originate from, this coloring can be quite variable from one tortoise to the next. A descriptive characteristic of the Red-footed Tortoise is their adult body shape, more pronounced in the male than the female.
The sides of the carapace become concave, almost giving it a 'waist'. The shape of the shell is often described as a loaf of bread or an hourglass. A medium size tortoise, they stay relatively small growing to about 12” to 16" (30 - 40 cm) for most types. The male is slightly larger than the female and has a longer, wider tail. On the juvenile Red-footed Tortoise, the carapace is lighter. It has a pale yellowish background color that develops into darker patches as it matures Red-footed Tortoises require warm, humid environments.
Extracted from the website of Animal World
