Scent Marking by Males of the Mediterranean Fruit Fly, Ceratitis capitata (Diptera: Tephritidae)
- Cite this article as:
- Shelly, T.E. Journal of Insect Behavior (2004) 17: 709. doi:10.1023/B:JOIR.0000042551.10590.d2
Males of the Mediterranean fruit fly, Ceratitis capitata (medfly), defend individual leaves as mating territories. While perching, males release an air-borne pheromone (known to attract females) from everted rectal epithelium at the tip of the abdomen. Males also occasionally touch the substrate with the tip of their abdomen. The main objective of the present study was to determine whether such abdomen dipping was a form of intersexual signaling, i.e., whether this action resulted in increased female visitation to the territory. Following observations on the frequency of pheromone calling and abdomen dipping of individually marked males, I ran a standard set of experiments using leaves from four different plant species. Leaves were exposed to varying numbers of (mature) males and females, respectively, for varying durations, and female settlement was compared on exposed versus nonexposed leaves in laboratory cages. Exposing leaves to females had no, or little, influence on female distribution for any of the four plant species. Exposing leaves to males had little influence on subsequent female settlement for orange, coffee, or macadamia trees. However, leaves of the fig tree Ficus bejamina that were exposed to males were much more attractive to females than nonexposed leaves. I then conducted a series of additional tests using fig leaves and found that i) leaf exposure to immature males had no effect on female distribution, ii) leaf exposure to mature males for as little as 90 min increased leaf attractiveness to females, iii) prohibiting males direct contact with the leaf during exposure eliminated any effect on female settlement, and iv) females discriminated between exposed and nonexposed leaves even in physically complex environments (i.e., potted plants). The possible role of abdomen dipping in sexual advertisement of male medflies is discussed.