ovipare

Ovipare is an adjective used in biology to describe organisms that reproduce by laying eggs, with embryos developing outside the parent’s body. In oviparous species, eggs are deposited and then incubated, often relying on yolk and additional membranes for nourishment and gas exchange.

Oviparity is contrasted with viviparity, in which offspring are born live, and with ovoviviparity, where eggs hatch inside the mother before birth. Many lineages use different strategies, and some species show mixed or facultative modes.

Examples include birds, most reptiles, amphibians, and many fishes, which lay eggs. Among mammals, the monotremes—the platypus and echidnas—are oviparous. A wide range of invertebrates also reproduce by laying eggs, such as insects, arachnids, mollusks, and crustaceans. Some sharks and rays are oviparous too.

Eggs vary in structure; birds and many reptiles produce shells, while others have soft or leathery coverings. Amniotic eggs contain membranes and yolk that support development on land. Invertebrate eggs range from simple capsules to complex protective coverings.

Oviparity has evolved repeatedly and offers advantages such as dispersal of offspring and reduced gestation burden. Disadvantages include vulnerability of eggs to predation and environmental hazards and a reliance on suitable incubation conditions. The strategy is a major feature of animal reproductive diversity.