Correlates of male quality in the field cricket, Gryllus campestris L: Age, size, and symmetry determine pairing success in field populations

Sexual selection in field crickets (Gryllidae) is well documented. Several studies have identified male traits, such as age and body size, that influence pairing success in the field. Here I show how these traits covary with male quality by examining the degree of fluctuating asymmetry in male Gryllus campestris. Older males were both larger and more symmetrical. Principal components analysis suggests that these three variables were essentially measures of the same trait, male quality. A comparison of paired and calling males showed that males of high quality were more successful in obtaining mates; paired males were older, larger, and more symmetrical. The area of the harp covaried with morphological traits and determined the carrier frequency of the male's call. Information related to male quality was therefore available for female discrimination.