Parthenogenesis

Parthenogenesis, growth of an organism from an unfertilized gamete, or sex cell (see Reproduction). It is common in the animal kingdom up through the class Insecta, but it occurs much more rarely thereafter. The mechanisms involved in the process are not yet well understood. A few kinds of amphibians, reptiles, and birds can reproduce parthenogenetically, but mammal embryos derived experimentally in this manner have thus far died within a period of days. Parthenogenesis also occurs, less commonly, among the lower plants. Among plants, the biological reproduction of fruit without fertilization is called parthenocarpy. Such fruit is seedless.