Abstract: Females of many insect species mate repeatedly during their lifetime and have the ability to store sperm from different mating males in sperm storage organs. As a result, sperm from different males compete to fertilize one female's eggs. Males display strategies for assessing female maternal quality, predicting future sperm competition risk, sperm heteromorphism and prolonged mating behavior. Females display strategies for assessing male paternal quality and the active manipulation of ejaculates to give precedence to different male sperm. These strategies reflect the influence of both natural and sexual selection.

Key words: insect, multiple mating, sperm competition, strategy