The relative concentrations of catecholamine in the nervous system of the entomophilic nematode Romanomermis culicivorax were measured under different experimental conditions by a glyoxylic acid-induced fluorescence procedure. A greater concentration of catecholamine was recorded in the nervous system of adult males and females than in postparasitic juveniles. A higher concentration of catechol...

Drosophila platonic (plt) males court females, but fail to copulate. Here we show that plt is an allele of scribbler (sbb), a BMP signalling component. sbb knockdown in larvae leads to the loss of approximately eight serotonergic neurons, which express the sex-determinant protein Doublesex (Dsx). Genetic deprivation of serotonin (5-HT) from dsx-expressing neurons results in copulation defects. ...

Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultra...

During the lifespans of most animals, reproductive maturity and mating activity are highly coordinated. In Drosophila melanogaster, for instance, male fertility increases with age, and older males are known to have a copulation advantage over young ones. The molecular and neural basis of this age-related disparity in mating behavior is unknown. Here, we show that the Or47b odorant receptor is r...

Increased understanding of geographic variation in courtship behavior in animal species can provide insight into the ways behavior may influence evolutionary change. Here, the relationship of geographic variation in courtship behavior to reproductive outcomes was tested in two distant and behaviorally distinct populations of brown-headed cowbirds, Molothrus ater, by comparing rates of copulatio...

Same-sex sexual interactions (SSSI) have been observed in many animal groups and have intrigued evolutionists. In this paper, reports on SSSI in Lepidoptera are reviewed and evolutionary hypotheses that could explain these behaviors are discussed. SSSI have been documented in males of 25 species and in females from role-reversed populations of one species. Four types of SSSI have been reported:...