Fast Track Evolution in Lizards

Rapid Adaptation of Italian Lizards Under Altered Environmental Conditions

Evolution is a prolonged and complex process which is achieved at the different levels of the organization of living material and which takes place in the different directions. The development of the biological organisms originated from the lowest forms, which have the relatively simple structure, to ever more complicated forms. Analyzing the historical development of organic peace and numerous concrete adaptations, there are three main directions of the evolution: aromorphosis, idioadaptation, and general degeneration.

Aromorphosis is the term for substantial evolutionary changes, which lead to complex structures and functions of organisms. Aromorphosis makes it possible for organisms to occupy fundamentally new niches or environments. Aromorphosis also essentially increases the ability of the organism to compete in the present environment in which it exists.

General degeneration is the term for evolutionary processes that lead to simplified structure and organization in organisms, such that they develop into parasites or sedentary creatures. The simplification or disappearance of a number of organs and tissues takes place, which results in a different type of live form. For the new life form to flourish under the new biological or physiological conditions, the organism must be able to compete and survive in the environment.

Idioadaptation referes to the changes that an organism makes in order to survive or thrive in the specific living conditions within the limits of the same adaptive zone. Idioadaptations are displayed in both aromorphosis and degeneration. These adaptations do not change the level of organization of organisms reached during evolution, but appreciably highten their chances of survival in given habitants.

A most interesting direction of evolution is adaptation to the environment. One example of adaption in animals can be seen in lizards. Lizards are part of a group of animals known as reptiles. They are most closely related to snakes. In fact, some lizards, called sheltopusiks, look like snakes because they have no legs. Many lizards today resemble the ancient reptiles of the dinosaur era. Their ancestors appeared on Earth over 200 million years ago. In general, lizards have a small head, short neck, and long body and tail. Unlike snakes, most lizards have moveable eyelids. Most lizards are less than 16 inches (40 centimeters) long. The world's largest lizard is the Komodo dragon, which can grow as long as 10 feet (3 meters) and weigh up to 300 pounds (135 kilograms). The smallest lizard species is a type of gecko. Measuring less than 3/4-inch (2 centimeters), this lizard is also the world's smallest reptile.