|Aluja, Martin - Institute De Ecologia - Mexico|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/25/2010
Publication Date: N/A
Technical Abstract: The outcomes of multiparasitism (host occupation by parasitoids of more than one species) are often predictable, one species typically outcompeting another. Such predictability may have arisen from asymmetrical iterations between competitors over evolutionary time. In some instances, a generalist parasitoid might confront a diversity of specialists, whereas a specialist parasitoid is likely to confront only the generalist. Consistent exposure to a particular generalist competitor may represent an opportunity for specialists to adapt and exert effective means of competition in dually parasitized hosts. Competition tests were carried out in the laboratory between Utetes anastrephae and Doryctobracon areolatus (Hymenoptera: Braconidae) in larvae of the Mexican fruit fly Anastrepha ludens (Tephritidae) to determine if the sequence of host exposure would influence progeny survival in either or both of the two parasitoids. Utetes anastrephae had a competitive advantage over D. areolatus when they occurred in multiparasitized hosts, and this advantage occurred regardless of the order in which the two parasitoids oviposited. That the specialist U. anastrephae could eliminate a more generalist competitor D. areolatus, probably through aggression, conforms to the hypothesis, although additional comparisons are required to confirm its generality.