The insulin signaling pathway has been implicated in several physiological and developmental processes. In mammals, it controls expression of 3-Hydroxy-3-Methylglutaryl CoA Reductase (HMGCR), a key enzyme in cholesterol biosynthesis. In insects, which can not synthesize cholesterol de novo, the HMGCR is implicated in the biosynthesis of juvenile hormone (JH). However, the link between the insul...

The growth of the head and neck and its components, including that of the vocal tract, is not homothetic but appears rather as an anamorphosis. The growth of various structures presents a phenomenon of heterochrony. Another important issue in vocal tract growth is sexual dimorphism. It was first claimed that sexual dimorphism appears at puberty, but a recent study has suggested that some prepub...

OBJECTIVE (1) To test the hypothesis that there are no developmental changes in the pharyngeal airway depth and hyoid bone position from childhood to adulthood in normal Taiwanese persons, (2) to identify any sexual dimorphism, and (3) to find the predictive value of selective variables for the hyoid bone position. MATERIALS AND METHODS Lateral cephalometric radiographs of 239 normal Taiwanes...

Sexual dimorphism is one of the most widespread and recognizable patterns of phenotypic variation in the biotic world. Sexual dimorphism in floral display is striking in the dioecious plant Silene latifolia, with males making many, small flowers compared to females. We investigated this dimorphism via artificial selection on two populations to determine whether genetic variation exists within p...

Sex differences in spatial learning have been reported in both humans and rodents. Correspondingly, there have been reports of sexual dimorphism in the morphology of the hippocampal formation (HF), a brain structure implicated in spatial cognition. In Experiment 1, we confirmed earlier reports that the overall volume of the granule cell layer (GCL) of the dentate gyrus (DG) of A/J mice is large...

Among Vespertilionidae species, sexual size dimorphism is very well documented, in which females are larger than males. The differences are mainly in body weight, skull measurements and forearm length. Studies have discussed some hypothesis for this phenomenon. However, very little information is known about sexual size dimorphism in Myotis nigricans (Schinz, 1821) in Brazil. In this sense, the...