1. Guppy (Poecilia reticulata): Guppies are small, live-bearing fish that are popular in freshwater aquariums. Female guppies can give birth to dozens of fry at a time, and they can reproduce multiple times throughout their lives.
2. Platy (Xiphophorus maculatus): Platies are another live-bearing freshwater fish that are often kept in aquariums. They are similar to guppies in terms of their reproductive behavior and can give birth to live fry on a regular basis.
3. Swordtail (Xiphophorus hellerii): Swordtails are larger live-bearing fish that are also popular in aquariums. Male swordtails have a distinctive elongated lower tail fin, giving them their name. Female swordtails can produce numerous fry during their reproductive cycles.
4. Molly (Poecilia sphenops): Mollies are another species of live-bearing freshwater fish. They come in various colors and patterns and are known for their hardiness and adaptability. Mollies can give birth to multiple broods of fry over the course of their lives.
5. Sailfin Molly (Poecilia latipinna): Sailfin mollies are known for their impressive dorsal fins, which can be longer and more elaborate in males. Like other live-bearing fish, sailfin mollies give birth to live young and can produce multiple broods over time.
These are just a few examples of viviparous fish that give birth. They reproduce by internal fertilization, and the female fish develop special tissues or structures within their bodies to nourish and protect the developing embryos until they are ready to be born as fully formed fry.