The importance of thyroid hormones in regulating early developmental processes of many amphibian and fish species is well known, but the impacts of exposure to disrupters of thyroid homeostasis during the embryo-larval-juvenile transitions are unclear. To investigate these impacts, fathead minnows, Pimephales promelas, were exposed to a model thyroid axis disrupter, methimazole, an inhibitor of...

SYNOPSIS. The endocrine mechanisms controlling the development and reproduction of flight-capable (longwinged) 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 hormone III (JH) haemolymph titres were quantified in adult worker honey bees under colony conditions conducive to either typical or accelerated behavioural development. JH titres of bees under conditions of accelerated behavioural development were significantly higher than same-aged bees under more typical conditions, even before the onset of foraging. These results are consistent wit...