SEXUAL SELECTION ON MULTIVARIATE PHENOTYPE IN ANASTREPHA FRATERCULUS (DIPTERA: TEPHRITIDAE) FROM ARGENTINA

ROBERTA B. SCIURANO; DIEGO F. SEGURA; MARCELA RODRIGUERO; PAULA GÓMEZ CENDRA; ARMANDO ALLINGHI; JORGE L. CLADERA; JUAN C. VILARDI

FLORIDA ENTOMOLOGIST

FLORIDA ENTOMOLOGICAL SOC

Año: 2007

0015-4040

Despite the interest in applying enviromentalls-friendly control methods, such as Sterile Insect Technique (SIT), against Anastrepha fraterculus (Wiedemann),  the information about its biology, taxonomy and behavior is still insufficient. To increase this information, the present study aims to evaluate the performance of wild flies under field-cage conditions through the study of sexual competitiveness among males (sexual selection). A wild population from Horco Molle, Tucumán, Argentina was sampled. Morphometric analyses were applied to determine the relationship between the multivariate phenotype and copulatory success. Mature virgin males and females were released from  into outdoor field cages to compete for mating within. Successful and unsuccessful males were measured for eight traits: head width (HW), face width (FW), eye length (EL), thorax length (THL), wing length (WL), wing width (WW), femur length (FL), and tibia length (TIL). Combinations of different multivariate statistical methods and graphical analyses were used to evaluate sexual selection on male phenotype. The results indicated that wing width and thorax length would be the most probable targets of sexual selection and described a nonlinear association between expected fitness and each of these two traits. This nonlinear relation suggested that observed selection could maintain the diversity related to body size.