Tephritidae Main | Diptera Home | SEL Home
Fruit Fly (Diptera: Tephritidae) Behavior
This section is mainly copied from Norrbom et al. (1999). More recent and more detailed reviews and analyses of most aspects of fruit fly behavior were published in Aluja & Norrbom (1999). Also see Biology, Host Plants, and Parasites & Predators.
Tephritids exhibit a wide array of interesting and sometimes spectacular behaviors in many aspects of their life, both as adults and larvae: in their dispersal, feeding, and oviposition behaviors, but especially in their courtship and mating. Males of many species secrete pheromones to attract females, and in some species gather in groups (leks) for this purpose. Males of some species fight for territories, including species of Phytalmia which have large genal processes used in these bouts (click here to see a video on Gary Dodson's page). Mate-guarding and male defense of food resources attractive to females have been reported. Courtship behavior may be complex and usually involves various types of body, leg, and wing movements, and/or transfer of a "nuptual gift" (trophallaxis) (see Sivinski et al. 1999: 751). Females often deposit a marking pheromone on the fruit (or other plant part into which eggs are laid) that deters oviposition by other females (see Díaz-Fleischer et al. 1999: 825).
Tephritid larvae live in and feed on various plant tissues, depending on the species. They may be single or gregarious, and resource partitioning is common among different species utilizing the same flower head of an Asteraceae species (Zwölfer 1983, 1988, Headrick & Goeden 1990). Species of Tephritinae that breed in Asteraceae (about 1/3 of all species) often have stout, spherical or subspherical maggots, apparently selected for their minimal need for movement. Such maggots usually pupate within the plant. Other tephritid larvae may move relatively long distances, first inside the plant tissues and then outside the plant, which they leave in order to pupate in the soil. In many frugivorous and florivorous species (e.g., many Dacina, Ceratitidina, Adramini and Blepharoneura), the larvae can jump several centimeters or more at a time (Fletcher 1987, Yuval & Hendrichs 1999: 431, M. A. Condon, pers. comm.).
Adults of many species, especially those that are univoltine and/or narrowly host specific, may spend most of their life on one plant or adjacent plants of the same species. Other species, especially those that are polyphagous, may have dispersive phases and may fly distances as great as tens or hundreds of kilometers, as in the case of some species of Anastrepha and Bactrocera (Christenson & Foote 1960, Fletcher 1989). Some multivoltine species of Tephritinae migrate with the seasons to a series of hosts at different altitudes in California (Goeden et al. 1987, Headrick & Goeden 1991). Larvae of a species of Blepharoneura are dispersed by frugivourous bats that carry their host fruits (Condon & Norrbom 1994). Tephritid foraging and host finding behaviors were reviewed by Prokopy & Roitberg (1989) and Katsoyanos (1989).
Feeding behavior, especially in nature, is a poorly understood aspect of tephritid biology (Hendrichs & Prokopy 1994). Adult nutritional requirements vary, largely depending upon the quality of the larval food (Tsitsipis 1989), and usually include at least carbohydrates and water, although some gall-forming species do not feed at all (Steck 1981, Freidberg & Kugler 1989). Many species also need amino acids, sterols, vitamins, and minerals to reproduce (Aluja 1994, Hendrichs & Prokopy 1994). In some species, including many that feed in galls or on seeds, females are proovigenic, i.e. they emerge with mature eggs and do not require protein for egg development, whereas in other species protein is needed for this purpose (synovigeny) and for optimal development of male salivary glands and pheromone production (Steck 1981, Landolt 1984, Hendrichs & Reyes 1987, Aluja 1994). Adults may feed on plant exudates, including those from oviposition holes or rotting fruit, bird feces, nectar, honeydew, and leachates, microorganisms, pollen and other matter on plant surfaces or in rain drops (Christenson & Foote 1960, Tsitsipis 1989, Hendrichs & Prokopy 1994). Microorganisms may play a role in the nourishment of some frugivourous species (Fletcher 1987, Howard 1989, Drew & Lloyd 1989). Adults of Blepharoneura (and probably Baryglossa and Hexaptilona, which have similarly modified labella) are unusual in being able to rasp and feed on plant tissues (Driscoll & Condon 1994, Condon & Norrbom 1994). In many fruit flies, both males and females have a premating development period of a week or more during which they do not mate (Steck 1981, Landolt 1984, Williamson 1989).
The appearance of some Tephritidae (e.g., Toxotrypana, some Anastrepha, some Pseudophorellia, various Adramini and Dacina) strongly suggests that they are wasp mimics, and at least in T. curvicauda this is reinforced by behavior (Knab & Yothers 1914). Other fruit flies with banded wings and/or spotted abdomens may be jumping spider mimics (Hasson 1995).
Many fruit flies mate on their host plants, but mating tactics vary, even within some species. Lek formation by males, usually on nonhosts, has been observed in Ceratitis capitata and species of Dacina, Anastrepha, Rhagoletis, and Procecidochares (Prokopy & Hendrichs 1979, Dodson 1986, Sivinski & Burk 1989, Aluja 1994). Males of most species of Tephritidae that have been studied secrete some type of sex-attractant chemical, either by inflating the lateral abdominal membranes or by extruding an anal pouch (Pritchard 1967, Headrick & Goeden 1994). They disperse these pheromones by wing fanning, which also produces sounds of possible significance in courtship (Sivinski & Webb 1985, Mankin et al. 1996). Males of many species of Bactrocera and Dacus have specialized structures, including a tibial pad, a microtrichose area of the wing, and a row of setae on the abdomen called the pecten, which are used for pheromone dispersal (I.M. White, pers. comm.). The pecten has been proposed as a stridulatory organ (Monro 1953, Kanmiya 1988). In Anastrepha robusta, the calling behavior includes short looping flights (Aluja 1993). Visual stimuli, as well as chemical and auditory stimuli, play an important role in communication between and among the sexes and with other insects. The body, which is often brightly colored, and the wings, which are usually patterned and are often held or moved in particular ways, no doubt act as releasers. Males of some species engage in antagonistic displays or bouts (Boyce 1934, Landolt & Hendrichs 1983, Headrick & Goeden 1994), including species of Phytalmia which have large genal processes used in these bouts (Moulds 1977). Mate-guarding and male defense of food resources attractive to females also have been reported (Hendrichs & Reyes 1987, Headrick & Goeden 1994, Opp et al. 1996).
Courtship can be elaborate in some species, or simple and brief in others. Headrick & Goeden (1994) defined 14 movements or behaviors that commonly occur in courtship, which may include various types of body, leg, and wing movements, and/or transfer of a nuptual gift (trophallaxis). The latter behavior has been observed in diverse taxa, including species of Dirioxa (Acanthonevrini), Anastrepha (Toxotrypanini), and various genera of Tephritinae (Freidberg 1986, Aluja, Jacome et al. 1993, Headrick & Goeden 1994). The gift may be passed before or after copulation, and it may consist of liquid transferred by direct contact of the mouthparts (Freidberg 1982, Aluja, Jacome et al. 1993) or may be a solidified froth deposited on the substrate (Stoltzfus & Foote 1965, Pritchard 1967, Novak & Foote 1975, Freidberg 1981, Jenkins 1990). Copulation is determined by female choice (Headrick & Goeden 1994) and may last from several minutes to several hours or more.
Oviposition behavior appears to be much more uniform than epigamic behavior and consists of the following stages: a) movement towards and arrival at the oviposition site; b) testing the site; c) drilling with the ovipositor; and d) oviposition. In the case of Anastrepha grandis, which lays a large batch of eggs in a tough, thick-skinned fruit, this process may last many hours (Gomes Silva 1991). Species in five genera have been reported to deposit a marking pheromone that deters oviposition by other females (Prokopy et al. 1976, Averill & Prokopy 1989, Straw 1989). This involves the female dragging her aculeus over the substrate, secreting and smearing the pheromone. In the case of Rhagoletis cerasi, the pheromone has been identified, synthesized, and used in orchards to combat damage to cherries (Aluja & Boller 1992).
See the Fruit Fly Bibliography Database for full information for cited references.
|Top of Page||
Content by Allen L. Norrbom. Last Updated: November 10, 2004.