How Did Turtles Evolve?


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A turtle Skeleton is that segment of turtle anatomy that represents the rear half of an alligator-like animal. The word “skeleton” comes from the Greek word skele, which means “wing”. When a turtle dies its heart, lungs and other soft bodied organs are pulled to the rear of its skull or “carapace”. Underneath these soft tissues is where the skeleton becomes complete. A preserved turtle skeleton revealing how the entire body and carapace connect with each other to form a fully-enclosed shell enclosing both the body and head.

turtle Skeleton

Turtle shells have been found in the cores of shallow, fresh water coral reefs throughout the world for over one hundred million years. During this time many species of prehistoric turtles survived by eating marine reptiles, small fish and scavenging for smaller fish eggs which they lay to nourish their young. At the same time, over half of all modern sea turtles are carnivores and their jaws can easily penetrate a turtle shell. Many fossil sea turtles have also been found with complete soft-shell bodies, indicating that they fed on these soft-shelled organisms for their nutrition during the Triassic period of earth history.

The fossil evidence reveals that the first stem Turtles appeared about thirty million years ago. During this time span modern sea turtles also gave rise to the first modern tortoises which eventually became birds. The evolution of turtles and tortoises can be traced through the fossil record and through the study of living turtles and tortoises. The development of the stem Turtles occurred alongside the evolution of birds in the Early Cretaceous geological strata.

A turtle skeleton consists of two parts: the plastrons and the exoskeletons. The plastrons are the under layers of the shell. Plastrons play an important role in protecting the body of the turtle from external harm. They also contain lots of vital organs that help in the proper growth and maintenance of the body. The states, on the other hand, are the outer layers of the shell.

There are several factors that can affect the evolution of the turtle shell and cause its shell to evolve. This includes ecological changes such as climate, habitat, prey competition, and the intensity of prey and predator attacks. Another factor is the impact of humans who initially hunted the species in the waters and were responsible for the extinction of certain species due to their destructive hunting techniques.

There are several theories on how turtles evolved. One theory states that these animals evolved from a common ancestor of modern turtles and chomped down to the ancestor of the tortoise. According to this theory, the modern turtles’ body structure is very much similar to that of its ancestor and through accumulation of many characteristics of its ancestor, the present day turtles evolved into a shell-less being. However, this theory has been rubbished over the years because the presence of several distinctively different species of turtles has been found in the fossil record.

Some other theories on how turtles evolved to include the theory of convergent evolution and gradual evolution. In the theory of convergent evolution, ancestral animals became more or less like their descendants, and gradually evolved into more developed forms. In the theory of gradual evolution, creatures changed very slowly from their ancestor to their descendant. An example of gradual evolution is the flightless birds, which first emerged from dinosaurs millions of years ago. The egg shells of these birds, which are actually the eggs of dinosaurs, can still be found in the ecosystem today.

A very well-known theory concerning how turtles evolved is through the process of gradual ontogeny. Osteogeny is the gradual reduction in the mass of the various bones of the body (including the skull, the spinal column, the jaws, the limbs, etc. ), and the greatest reduction takes place at the time of metamorphosis (recombining) or molting. Through these processes, the size of an organism becomes smaller and increases its weight at the same time. During metamorphosis, the rate of bone loss and growth are greater than at any other point in an organism’s lifetime. Thus, when the turtle molts or re-emerges from its shell, it has lost most, if not all, of its former shell, including the anterior carapace, and has evolved back to its fully grown adult size.

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