selffertilizing

Selffertilizing, or self-fertilization, describes the biological ability of an organism to produce offspring using its own genetic material, without requiring fertilization from a different individual. In flowering plants, self-fertilization typically occurs through self-pollination, when pollen from a flower's anthers lands on its own stigma or on another flower from the same plant and fertilizes the ovules.

Benefits include reproduction when pollinators are scarce or individuals are isolated, and the rapid fixation of favorable traits. However, self-fertilization reduces genetic diversity and can lead to inbreeding depression due to the accumulation of deleterious recessive alleles.

Plants may possess barriers to selfing or mechanisms that promote it: self-compatibility allows selfing, while self-incompatibility systems, dichogamy (temporal separation of male and female function), and herkogamy (spatial separation of reproductive organs) promote outcrossing. Many crop species are naturally self-fertilizing, such as wheat, rice, and peas, which can produce seeds without partners.

In animals, selffertilization occurs in some hermaphroditic species, where eggs and sperm from the same individual combine. Examples include certain flatworms, terrestrial snails, and nematodes such as Caenorhabditis elegans, which can self-fertilize but may also outcross when mates are available.

Evolutionarily, the balance between selfing and outcrossing varies and is influenced by ecological conditions, pollinator availability, and mating-system genetics.