In the context of reproduction, what does viviparous mean?

Viviparous refers specifically to a mode of reproduction where organisms give birth to live young that have developed inside the mother's body. In viviparous species, fertilization occurs internally, and the developing embryos are nourished directly by the mother's body through a placental structure or other means, allowing for more complex development and better survival rates for the offspring. This term is commonly used in reference to mammals, including humans, but can also apply to some reptiles and fish that exhibit this reproductive strategy.

The concept of viviparity contrasts with other reproductive strategies, such as oviparity, where eggs are laid outside the body to develop independently. In this context, the distinction is clear: viviparous organisms invest in the development of their young and provide them with a more protected environment until they are ready to be born. This can confer advantages in terms of offspring survival and adaptation to environmental stresses.