SUPPORT FOR THE IMMUNOCOMPETENCE HANDICAP HYPOTHESIS IN THE WILD: HORMONAL MANIPULATION DECREASES SURVIVAL IN SICK DAMSELFLIES

摘要: The immunocompetence handicap hypothesis (ICHH) states that hormones enhance sexual trait expression but impair immunity. Previous tests of the ICHH have been hampered by experimental design problems. Here, we report on an test includes manipulations both and infections in males territorial damselfly, Hetaerina americana, with accurate survival measurements. We conducted a fully factorial experiment subjecting each individual to one three topical treatments: methoprene (a juvenile hormone analog), acetone, or control, injection bacteria, PBS, control. measured manipulated wild captivity. As predicted, was most heavily impaired methoprene-bacteria than other groups wild, no differences emerged captive animals. This result confirms is cost animal pays for increased hormonal levels. corroborates theoretical predictions ICHH.