Vivipary

A viviparous animal is an animal employing vivipary: the embryo develops inside the body of the mother, as opposed to outside in an egg (ovipary). The mother then gives live birth. The less developed form of vivipary is called ovoviviparity, which, for instance, occurs in most vipers. The more developed form of vivipary is called placental viviparity; placental mammals are the best example, but other animals have also adapted by incorporating this behavior, such as in scorpions, some sharks, some snakes, and in velvet worms. Certain lizards also employ this method such as the genera Tiliqua and Corucia. The placenta is attached directly to the mother in these lizards which is called viviparous matrotrophy. Viviparous offspring live independently and require an external food supply from birth. There are numerous advantages and disadvantages to being viviparous.