THE IMPORTANCE OF SEQUESTERED IRIDOID GLYCOSIDES AS A DEFENSE AGAINSTAN ANT PREDATOR

Authors
Citation
La. Dyer et Md. Bowers, THE IMPORTANCE OF SEQUESTERED IRIDOID GLYCOSIDES AS A DEFENSE AGAINSTAN ANT PREDATOR, Journal of chemical ecology, 22(8), 1996, pp. 1527-1539
Citations number
29
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Ecology,Biology
Journal title
ISSN journal
0098-0331
Volume
22
Issue
8
Year of publication
1996
Pages
1527 - 1539
Database
ISI
SICI code
0098-0331(1996)22:8<1527:TIOSIG>2.0.ZU;2-S
Abstract
We reared larvae of Junonia coenia Hubner (Nymphalidae) on artificial diets with trace concentrations of iridoid glycosides and on leaf diet s with higher concentrations of iridoid glycosides. We offered these c aterpillars to predacious ants and observed the effects of the followi ng on predation: diet (artificial vs. leaf), site (ant colonies in dry vs. wet areas), instar (early vs. late), and time (changes in predati on over five days). Diet and site were consistently significant predic tors of the ants' propensities to reject prey and the caterpillars' ab ilities to escape predation. Leaf-diet caterpillars escaped more frequ ently than artificial-diet caterpillars, and ants from dry sites were more likely to reject prey than ants from wet sites. The percentage of iridoid glycosides found in individual caterpillars was also a good p redictor of the probability of rejection by predators and prey escape. Caterpillars with higher levels of iridoids were more likely to be re jected and to escape, suggesting that sequestered iridoid glycosides a re a defense against predaceous ants.