/jp/ - Otaku Culture

Male stalk-eyed flies have the ability to ingest air and lengthen their eyestalks, which they use in mating season to compete with other males in eyestalk-measuring contests.

A freak of sexual selection, stalk-eyed fly females prefer males with long eyestalks, so the males aggregate in leks and compare their stalk sizes like fratboys comparing their dicks. Some males even have the ability to gulp air and extend their eyestalks like a weiner balloon.