 It has been found in "Drosophila" that there is a positive correlation between the length of male sperm tails and the size of the seminal receptacle found in females.It has been found that females with larger seminal receptacles “choose” sperm with long tails over sperm with short tails.Although females seem to “favor” this trait, no reproductive advantage for long tails has been found except for better correspondence to females with large seminal receptacles.