Ovoviviparous animals produce eggs inside their body, but then give birth to live young. The eggs hatch out inside the mother and the offspring stay within her for a time. She later gives birth to the them. While they are within her, the young are fed on the yolk of the egg, and not directly from the mother's body. Ovoviviparity is a special type of viviparity. Some fish, amphibians and reptiles reproduce this way, for instance the sand tiger shark.
Slow worms develop young inside their bodies.
Living in the crevices between rocks, slow worms hunt by day for slugs, snails, small insects and spiders. The females give birth during summer, when up to a dozen partly developed young are born in a birth sac which soon breaks open. Developing the young inside her body keeps them at a stable temperature, protecting them from the extremes of Britain's weather.
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