Immunoecology of Species with Alternative Reproductive Tactics and Strategies
Table 1
Contrasting predictions about the relationship between sexual signals and immunity, depending on whether testosterone lowers immune function [60], or the reverse mechanism, that immune activation lowers testosterone [66].
Experimental treatment
T lowers immunity
Immunity lowers T
Increase in T
(1) Decreased immunity (2) More elaborate sexual traits
(1) No direct effect on immunity (2) More elaborate sexual traits (3) If resources are lacking, a decrease in all other energy requiring functions, not just immunity
Immune challenge
(1) No effect on T (2) Decreased sexual traits-due to energetic requirements
(1) Decrease in T (2) Decreased sexual traits-due to energetic requirements and lower T
Information gleaned from sexual traits
Willingness to increase T and risk disease at the time sexual traits developed.
Low exposure to parasites at the time sexual traits developed.
