Ovoviviparous refers to a reproductive strategy in which animals produce eggs that develop and hatch inside the mother's body. Unlike viviparous animals, which give live birth, ovoviviparous species retain the eggs within them until they are ready to hatch. This allows the young to be born in a more developed state, increasing their chances of survival. Many species of sharks, snakes, and lizards exhibit ovoviviparity. In these animals, the embryos receive nourishment from the yolk of the egg rather than from the mother directly. This method of reproduction is advantageous in environments where external conditions may be harsh for developing eggs.