Reptile reproduction

Ok, having dealt with birds, let me move on to reptiles. Firstly, most reptiles lay eggs. Reptiles that lay eggs are called oviparous. Some reptiles bear live young, and the term for this is viviparous. We will focus more on oviparous reptiles.

Males and females possess different reproductive organs. The male possesses two testicles, housed inside the body. The male also has a copulatory organ, either a single penis (turtles and tortoises, crocodilians) or a pair of hemipenes (lizards, snakes) that can often be seen as two bulges behind the cloaca at the base of the tail. The penis or hemipenis is not connected to the urinary tract, and is strictly an organ of reproduction. A female has ovaries which store eggs.

For fertilization, a male reptile inserts either one of his two hemipenes into the female's cloaca, or the single penis is inserted. Before actual copulation, the pair usually engages in some type of ritualized courtship. After copulation, sperm can be stored for up to six years, and this stored sperm can fertilize subsequent clutches without additional contact by a male.
Using the green iguana as an example, even without a male present to fertilize eggs, a healthy adult female may begin developing eggs. The process begins with the ovaries, where eggs are stored. Follicles begin developing in the ovaries. Each follicle is composed of a tiny egg and a sac filled with yolk. The follicles then detach and move into the oviducts where the egg white is added, and then a shell is placed around the yolk and white. The female usually will not eat for three to six weeks prior to laying her eggs.

A gravid female would naturally dig a large burrow in moist soil (often along a riverbank) in the wild when she wants to lay her eggs. Then, she will deposit the eggs and completely cover the hole, hiding any evidence of her activities.

Female pythons are one of only a few groups of reptiles to care for her eggs after oviposition. A female will coil around her eggs until they hatch, protecting the eggs and providing temperature regulation, as well. Crocodilians also assist the hatchlings as they emerge from their nests, and will guard them for a while after hatching.

In the species that give birth to live young, some species show a degree of maternal care. Some skinks will assist the neonates by helping them escape from their birth sacs. The Solomon Island skink gives birth to one very large offspring after a long gestation period and while pregnant, she will eat very little. Snakes, such as the boas and garter snakes also give birth to live young.

Now back to egss. In captivity, eggs are usually removed and placed in an incubator. Vermiculite is moistened with bottled water and the eggs are buried halfway. Eggs should be handled carefully, and care should be taken to not change the position that they were in when deposited.

The eggs of some species are hard (turtles, tortoises, crocodilians and some lizards, especially geckos), and those of others are more leathery (snakes and most lizards) Incubation time can vary from about 45 days (in small lizards) to over a year (for some tortoises).
When it is time for the baby to hatch, the neonate uses its egg tooth (also called caruncle) to cut through the eggshell. The baby will usually remain in the egg for 12-48 hours after it pokes its head through the egg. During that time, any remaining yolk still attached to the hatchling will be absorbed.
Babies hatched from eggs, as well as those that are born alive from the female, are able to fend for themselves as soon as they are up and walking around/slithering.

I thank www.exoticpetvet.net/reptile/rerepro.html for the information