Stalk-eyed Fly, The Gambia.

Diopsid flies are certainly some of the strangest-looking insects, the extreme modification of the head into two long stalks lending them an other-worldly appearance. Perhaps even more interesting is the evolutionary mechanism underlying this bizarre anatomy, whereby female flies show a strong preference for males with larger eye-stalks. This so called sexual selection is also the process responsible for development of exaggerated ornaments in other animals such as peacocks.