Chemical Defense as a Condition-Dependent Trait in Harvestmen

Author(s)

Nazareth, Tais M. ; Sudatti, Daniela B. ; Machado, Glauco

• Document type: Journal article
• Source: Journal of Chemical Ecology; v. 42, n. 10, p. 1047-1051, OCT 2016.
• Web of Science Citations: 2

Abstract

The expression of costly traits often depends on the amount of food available to the individuals. Chemical defenses are costly, thus their production should be condition-dependent. Here, we tested the hypothesis that an increase in food availability and an acetate-supplemented diet will increase the production of chemical defenses by the harvestman Magnispina neptunus, which releases alkylated benzoquinones biosynthesized using acetate as a precursor. We manipulated the diet of the individuals and created four experimental groups: well-fed with acetate, well-fed without acetate, poorly-fed with acetate, and poorly-fed without acetate. Well-fed individuals produced secretions with higher mass and concentration of benzoquinones than poorly-fed individuals, but we detected no significant effect of the acetate supplement. Thus, the production of benzoquinones is condition-dependent, and even short periods of dietary restriction may make individuals more vulnerable to predators, imposing fitness consequences to chemically-protected arthropods that biosynthesize their own defensive compounds. (AU)

• FAPESP's process: 12/50229-1 - Macroecology of sexual selection: large-scale influence of climate on sexually selected traits
• Grantee: Glauco Machado
• Support Opportunities: Regular Research Grants