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Two frogs mating surrounded by eggs

Spawning

Spawning animals deposit a mass of eggs and sperm in water, where they meet and are fertilised. Even when the male and female animals are in close proximity, such as a male frog grasping the female, the eggs are fertilised outside the female's body. Some animals, such as coral and many fish, synchronise their spawning so that millions of eggs are released at once in often quite impressive events.

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About

Spawn is the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning. Most aquatic animals, apart from aquatic mammals, reproduce through a process of spawning.

Spawn consists of the reproductive cells (gametes) of aquatic animals, some of which will become fertilized and produce offspring. The process of spawning typically involves females releasing ova (unfertilized eggs) into the water, often in large quantities, while males simultaneously or sequentially release spermatozoa (milt) to fertilize the eggs.

Most fish reproduce by spawning, and so do most other aquatic animals, including crustaceans such as crabs and shrimps, molluscs such as oysters and squid, echinoderms such as sea urchins and sea cucumbers, amphibians such as frogs and newts, other amphibious animals such as turtles, aquatic insects such as mayflies and mosquitoes, and corals (which are small aquatic animals and not plants). Fungi, such as mushrooms, are also said to "spawn" a white fibrous matter that forms the matrix from which they grow.

There are many variations in the way spawning occurs, depending on sexual differences in anatomy, on how the sexes relate to each other, on where and how the spawn is released, and on whether or how the spawn is subsequently guarded.

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