Ecdysteroids are important hormones that regulate moulting in arthropods. Three-host ixodid ticks normally moult to the next stage after finishing their blood meal, in the off-host environment. Presumably, three-host ticks that feed on the blood of insectivorous vertebrate hosts can be exposed to high levels of exogenous ecdysteroids causing them to initiate apolysis (the first step of moulting...

Previous studies on wild moulting waterfowl have demonstrated that flight and leg muscles experience periods of hypertrophy and atrophy. This is thought to be in response to the change in use of the locomotor muscles as described in the use/disuse hypothesis. We tested this hypothesis using captive barnacle geese. Forty geese were dissected before, during and after wing moult, to determine the ...

Angiostrongylus cantonensis is a parasitic nematode that needs to develop in different hosts in different larval stages. Freshwater snails, such as Pomacea canaliculata, are the intermediate host, and rats are the definitive host. Periodic shedding of the cuticle (moulting) is an important biological process for the survival and development of the parasite in the intermediate and definitive hos...

Understanding the causes of variation in feather colour in free-living migratory birds has been challenging owing to our inability to track individuals during the moulting period when colours are acquired. Using stable-hydrogen isotopes to estimate moulting locality, we show that the carotenoid-based yellow-orange colour of American redstart (Setophaga ruticilla) tail feathers sampled on the wi...

* John D. Jones Scholar, 1940. Abramowitz, R. K., and Abramowitz, A. A., "Moulting, Growth, and Survival after Eyestalk Removal in Uca pugilator," Biol. Bull., 78, 179-188 (1940). Brown, F. A., Jr., "An Internal Secretion Affecting Viability in Crustacea," Proc. Nat. Acad. Sci., 24, 551-555 (1938). Brown, F. A., Jr., and Cunningham, O., "Influence of the Sinusgiand of Crustaceans. on Normal Via...

Cytochrome P450 superfamily proteins play important roles in detoxification of xenobiotics and during physiological and developmental processes. To contribute to our understanding of this large gene family in insects, we have investigated the function of the cytochrome P450 gene LmCYP4G102 in the migratory locust Locusta migratoria. Suppression of LmCYP4G102 expression by RNA interference (RNAi...

Ambient calcium is declining in thousands of soft-water lake habitats in temperate regions as a consequence of unsustainable forestry practices, decreased atmospheric calcium deposition and acidic deposition. As their exoskeleton is heavily reinforced with calcium, freshwater crustaceans have a high specific calcium requirement relative to other aquatic organisms. Daphnia, in particular, is an ...