Life Cycle of a Snake

Snakes, as we all know, are elongated and legless reptiles, commonly distributed all over the world, except in Antarctica. As of now, about 2,900 species of snakes have been identified. They belong to the order Squamata and suborder Serpentes. As per evidences, snakes evolve either from burrowing or water lizards. However, unlike other legless lizards, snakes lack movable eyelids and external ears. They possess loosely articulated skulls, overlapping scales and flexible lower jaw for swallowing their prey. Snakes are carnivorous and feed on a wide variety of animals like insects, birds, frogs, snails, lizards, eggs and other snakes.

Snakes are quite diverse in terms of their size and other characteristics. Their size may range from a short 10 cm long to the huge anacondas, which are about 25 ft long. They are classified based on their shape and the number of scales on the head. In general, there are two types of snakes, venomous (that have venom) and non-venomous (without venom). Venomous snakes use their venom for killing their prey and also for self-defense. Those venomous species that are capable of biting and causing painful injury and/or death to humans are classified as poisonous snakes. Let's take a look at the life cycle of a snake.

Life Cycle of a Snake

Depending upon the climatic conditions, the mating season of snakes vary. In colder regions, spring is the mating season; whereas, snakes can undergo mating in any season in case of tropical regions. The females secrete pheromones and leave behind as they move, in order to attract the males. A male snake after getting the signal follows the female for courtship. Very rarely, male snakes indulge into fierce battle for the female snake.

During the courtship, the male snake lifts the tail of the female with the help of its own tail for copulation. The male snake then deposits the sperms by inserting one of its two hemipenes (small sacs on the underside of the tail) into the cloaca of the female snake. In some snake species, fine spines are present on the hemipenes for holding the female during copulation. Mating may last from a few minutes to several hours. A female snake can mate with the same or different male several times during the mating season.

After mating, the female snake stores the sperms in the oviduct for about 1 - 2 months. The female then produces large eggs, which after releasing from the ovary are fertilized by the sperms from the oviduct. The female lays the fertilized eggs in shallow holes or under the rocks. The outer covering of snake's egg is not hard, rather it resembles a soft leather. The female snake guards and looks after the eggs till they hatch.

Some snake species warm the eggs in order to speed up the hatching process by twitching their muscles. It is found that about 20 percent of the total snake species, especially those adapted in cold regions, give birth to young ones. Some female snakes lay eggs even without fertilization, which is referred to as parthenogenesis. The juvenile snake comes out of the egg, by biting the egg cover with the help of egg tooth. As the juvenile snakes hatch, they attain maturity within 2 - 4 years.

One of the major distinguishing features between a younger snake and a older snake is the frequency of moulting per year. In case of a growing snake, skin shedding takes place about four times a year, whereas an older snake sheds only once a year, at the most two times per year. However, unlike insects in which moulting allows the growth of the organism, renewal of skin in snakes does not have a significant role in their growth. Moulting serves two functions, to replace the old skin and to get rid of parasites, which inhabit the old skin. A snake can survive to about 20 - 30 years. Nevertheless, due to natural predators and disease conditions, it hardly survives till the old age.