Snakes are the most modern of reptiles but perhaps the least understood reptiles. Most people are afraid of snakes, even those with an educated understanding of the environment and nature. This is unfortunate because the average snakes that turns up in the backyard or the forest is usually harmless harmless. Many snakes are even helpful to humans. This paper will help to clarify which are indeed dangerous and how to detect them. Snakes inhabit a wide variety of ecologic habitats such as land, trees, underground, fresh water, and salt water. They are found on every continent except Antarctica. .
Snakes are the most modern of reptiles. They first appear in the fossil record during the time of the dinosaurs. Their fossil history is not very well known because snake skeletons are very delicate and do not fossilize easily. By carefully examining what they have found and comparing it to other close relatives such as lizards, scientists have been able to construct a theory about their evolution. Snakes, like all living things have evolved, which allows them to adapt over time in response to the environment and other factors to produce entirely new species. This is known as natural selection. Those animals with superior traits live longest and reproduce. Snakes are thought to have evolved originally from a group of ancient amphibians knows as the labrynthodonts. They were called that because of their distinctive teeth, which were shaped, in a mazelike pattern. Reptiles developed from these amphibians as a result of shelled eggs which were able to be laid on land and did not require water. These reptiles began a burrowing way of life. They tunneled though dirt in search of earthworms and other food. Over millions of years they lost their external limbs and their ears so they were able to burrow more easily. At the time that dinosaurs were becoming extinct, these snakes began coming to the surface. They then developed a new legless mode of locomotion and diversified into many ecological niches.