- alicias7768Lv 71 decade agoFavorite Answer
Most fishes are egg-layers, but many bear living young. Live-bearing fishes may be ovoviviparous, in which the eggs essentially simply hatch within the female, or viviparous, in which the unborn young are supplied nourishment through the mother's tissues. In some ovoviviparous fishes the embryo develops in the egg while the egg is still within its follicular covering within the ovary, and ovulation (or release of the egg) and birth occur at the same time. In other ovoviviparous forms the eggs are released from the protective follicles into the cavity of the hollow ovary, where development continues. In some viviparous fishes the walls of the egg follicle are in intimate contact with the embryo, supplying it with nourishment. In the viviparous sharks, a part of the oviduct, or egg channel, is developed into a uterus, where the modified yolk sacs of the young are closely joined to pockets within the uterus.
In live-bearing fishes and in some egg-layers, fertilization occurs internally, and methods have been evolved for introducing the sperm into the female's body. In sharks the pelvic fins of the male are modified into intromittent organs called myxoptergia, and in the male topminnows the anal fin is modified into a similar-functioning intromittent organ called the gonopodium.
At least three modes of reproduction--heterosexual, hermaphroditic, and parthenogenetic--are found in fishes. In the most common form, heterosexual reproduction, there are separate male and female parents, but even here there is considerable variation. In some live-bearing fishes, the female is able to store sperm for up to 8 or even 10 months, and this sperm is used to fertilize new batches of eggs as they develop. In some cases, a female may carry sperm from several males at once.
In hermaphroditic reproduction, a single fish is both male and female, produces both eggs and sperm (either at the same time or at different times), and mates with other similar hermaphroditic fishes. External self-fertilization occurs in one hermaphroditic fish, which sheds egg and sperm simultaneously. In another, internal self-fertilization may occur. In certain fishes there is a time sequence of hermaphroditism, young fishes reversing their sex as they grow older.
In parthenogenetic reproduction, unfertilized eggs develop into embryos. This is known to exist in at least one fish species, Poecilia formosa, of the Amazon River; however, even though development proceeds without fertilization in some of these females, mating with a male is still required to stimulate egg development.
Parental care also shows great diversity. Some fishes, like the Atlantic herring, form huge schools of males and females and freely shed their eggs and sperm (milt), and then abandon the eggs. Other fishes build nests and care for both the eggs and newly hatched young. Others have evolved methods of carrying the eggs with them, commonly in their mouths, but also in gill cavities or in special pouches on the body.
- SnaglefritzLv 71 decade ago
Depends on the type of fish. Live bearers do it when no one looking and the Female get pregnant and have her babies live like people. Bettas are egg layers and actually beautiful to watch, but, only when they ready. The male builds a bubble nest and will caress his mate squeezing the eggs from her and fertilizing them. Then he puts them into the nest and cares for them. The female must be removed or the male kill her. Angel fish, the female lays the eggs on a rock, or, whatever and the male fertilize them. They both care for the nest and babies together. That three ways how it done, and, there many others. Just depends on the type of fish.
- 1 decade ago
depends on what kind of fish you have....live bearers have sex the same way other "animals" do, as in males have a 'penis' and females have the opening. If they are egg layers, they don't actually have sex, they fertilize the eggs outside of the female body.Source(s): used to breed fish
- abfabmom1Lv 71 decade ago
The female fish lays her eggs (usually in a safe spot that still gets a lot of water movement to keep them aerated).
Then, the male swims by and sprays his sperm over the eggs to fertilize them.
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- VerniekeLv 44 years ago
Well after sex women sleep in their own wet spot don't they ?
- Penny MaeLv 71 decade ago
Do you know about the birds and the bees???????? Yes they do and they have babies too. Mine just had some and they are so tiny and cute. How about on a waterbed!!!!!!Low lights, soft music, and one thing leads to another and bam... the deed is done.
- 1 decade ago
They don't they lay eggs and the male fertiles it
- Anonymous6 years ago
It depends on the type of fish...
- 1 decade ago
The females lay eggs and the male fertilizes them.
- 1 decade ago
I dont need to tell u. As the others are right.