Viviparity

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Vivparous animals have internal fertilisation and the eggs develop inside the mother. It is the standard method for all mammals except monotremes, and for many reptiles.

However, vivparous reptiles mostly keep soft-shelled eggs inside their bodies, and the embryo exists on the material in the egg. This is ovoviviparus, because of the source of nutrition. There are some amphibia and some reptiles which are genuinely viviparous because the get their nutrition from a placenta or directly from the mother's blood supply.

In plants[change | change source]

Poa alpina, a grass which shows vivipary: the seeds germinate while still attached to the mother plant.

Viviparous plants produce seeds that germinate before they detach from the parent. In many mangroves, for instance, the seedling germinates and grows under its own energy while still attached to its parent. Then it drops into the water to transport away. In some trees, like Jackfruit, the seeds can be found already germinated while the fruit goes overripe; this condition cannot be said as vivipary since the moist and humid conditions provided by the fruit mimics a wet soil that encourages germination. However, the seeds can germinate under soil too.[1]

References[change | change source]