There are well documented costs of mating in insects but little evidence for underlying mechanisms. Here, we provide experimental evidence for a hormone-based mechanism that reduces immunity as a result of mating. We examined the mealworm beetle Tenebrio molitor and show that (i) mating reduces a major humoral immune effector-system (phenoloxidase) in both sexes, and (ii) that this down-regulat...

The endocrine mechanisms controlling the development and reproduction of flight-capable (long-winged) and flightless (short-winged or wingless) morphs of wing-polymorphic insects have been intensively investigated. The "classical model," put forward in the early 1960s, postulates that morph-specific differences in development and reproduction are caused by variation in the titers of juvenile ho...

The body cells of the developing insect carry the potentialities for both larval and imaginal differentiation. During larval life imaginal differentiation is suppressed because in the presence of the juvenile hormone (sometimes referred to as the 'inhibitory hormone'), secreted by the corpus allatum, the intracellular system which leads to the formation of larval structures takes precedence ove...

The effects of the social environment and age on juvenile hormone (JH) and reproduction were investigated by measuring ovarian development, hemolymph levels of JH III, and rates of JH biosynthesis from the same individual bumble bees (Bombus terrestris). Differences in social environment were associated with differences in rates of JH biosynthesis, JH titer and ovarian development. Young queenl...

We have recently discovered ethyl 4–(2–benzylhexyloxy)benzoate (KF–13) as a novel anti–juvenile hormone (anti–JH) agent (Furuta et al., 2007). This compound induced precocious metamorphosis in larvae of the silkworm, Bombyx mori, a clear sign of JH deficiency, and its activity could be completely counteracted by the simultaneous application of methoprene, a JH agonist. Although KF–13 induced ob...