Neriid Flies (IMAGE) University of Chicago Press Journals Caption A pair of mating neriid flies (Telostylinus angusticollis) illustrating the male's strikingly elongated legs, a sexually selected trait used by males in competition for mates. In many other species of flies, similarly elongated legs occur in both sexes and appear to serve survival-related functions. Could the evolution of long legs and associated ecological strategies have been initiated by sexual selection on males? Credit R. Bonduriansky © Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.