Herkogamy is a key floral trait thought to promote outcrossing or the avoidance of interference between male and female sexual functions. Herkogamy may serve primarily to reduce sexual interference in self-incompatible species, whereas, in self-compatible plants, it is usually regarded as an adaptive trait that reduces the likelihood of self-pollination and increases the possibility of outcrossing. The placement of male (staminate) and female (pistillate) flowers in different positions within the same plant in bisexual flowers; for example, a heterostylous species is also a herkogamous species. It favours cross-pollination.