Search results for "TSH"
showing 10 items of 139 documents
Volatile Drosophila cuticular pheromones are affected by social but not sexual experience.
2012
International audience; Recognition of conspecifics and mates is based on a variety of sensory cues that are specific to the species, sex and social status of each individual. The courtship and mating activity of Drosophila melanogaster flies is thought to depend on the olfactory perception of a male-specific volatile pheromone, cis-vaccenyl acetate (cVA), and the gustatory perception of cuticular hydrocarbons (CHs), some of which are sexually dimorphic. Using two complementary sampling methods (headspace Solid Phase Micro-Extraction [SPME] and solvent extraction) coupled with GC-MS analysis, we measured the dispersion of pheromonal CHs in the air and on the substrate around the fly. We als…
Prospero mutants induce precocious sexual behavior in Drosophila males.
2007
0001-8244 (Print) Journal Article Research Support, Non-U.S. Gov't; Brain maturation, a developmental process influenced by both endogenous and environmental factors, can affect sexual behavior. In vertebrates and invertebrates, sexual maturation is under the influence of hormones and neuromodulators, but the role of developmental genes in this process is still poorly understood. We report that prospero (pros), a gene crucial for nervous system development, can change the age of onset of sexual behavior in Drosophila melanogaster males: adult males carrying a single copy of several pros mutations court females and mate at a younger age than control males. However, these pros mutations had n…
Contact with attractive women affects the release of cortisol in men
2010
Previous studies have shown that situations relevant for human mating can affect the levels of many hormones. This study focused on the hypothalamus-pituitary-adrenal axis by measuring salivary cortisol levels in 84 young men prior to and after a period of short social contact with a woman or man. Results showed that after contact with another man the cortisol levels of the participants declined according to the circadian release pattern of cortisol. However, cortisol levels in men declined less when they had contact with a woman. Furthermore, cortisol levels of men increased when they perceived the woman with whom they had contact as attractive. Our findings provide indirect evidence for t…
MALE COURTSHIP SONG AND FEMALE PREFERENCE VARIATION BETWEEN PHYLOGEOGRAPHICALLY DISTINCT POPULATIONS OF DROSOPHILA MONTANA
2007
Understanding the variation within and between populations in important male mating traits and female preferences is crucial to theories concerning the origin of sexual isolation by coevolution or other processes. There have been surprisingly few studies on the extent of variation and covariation within and between populations, especially where the evolutionary relationships between populations are understood. Here we examine variation in female preferences and a sexually selected male song trait, the carrier frequency of the song, within and between populations from different phylogeographic clusters of Drosophila montana. Song is obligatory for successful mating in this species, and both …
Two distinct genomic regions, harbouring the period and fruitless genes, affect male courtship song in Drosophila montana
2012
Acoustic signals often have a significant role in pair formation and in species recognition. Determining the genetic basis of signal divergence will help to understand signal evolution by sexual selection and its role in the speciation process. An earlier study investigated quantitative trait locus for male courtship song carrier frequency (FRE) in Drosophila montana using microsatellite markers. We refined this study by adding to the linkage map markers for 10 candidate genes known to affect song production in Drosophila melanogaster. We also extended the analyses to additional song characters (pulse train length (PTL), pulse number (PN), interpulse interval, pulse length (PL) and cycle nu…
Cuticular hydrocarbons of Drosophila montana: geographic variation, sexual dimorphism and potential roles as pheromones.
2014
Abstract Sexual selection within populations can play an important role in speciation when divergence in mating signals and their corresponding preferences occur along different coevolutionary trajectories in different populations. In insects, one potential target of sexual selection is the blend of cuticular hydrocarbons (CHCs), which often show intra- and interspecific variation, sexual dimorphism and may act as pheromones. In Drosophila montana, a cold-adapted, circumboreal member of the Drosophila virilis species group, flies from different populations have been found to show significant premating isolation as well as variation in male mating signal (song) and female preference. While t…
Coping with stress in different phases of romantic development
2001
The degree to which coping with stress in romantic relationships is related to relationship development was examined longitudinally in a sample of early adolescents (n=107). Repeated measures ANOVAs revealed a significant decrease in romantic stress over time, while at the same time active coping with romantic stress increased. Concurrently, the quality of romantic relationships changed towards greater intimacy and affection. The results provide some support for recent theories of a developmental sequence in romantic relationships, according to which relationships progress from a more casual initial stage towards a more committed affection phase. In addition, the study illustrates that the …
The effects of reproduction on courtship, fertility and longevity within and between alternative male mating tactics of the horned beetle, Onthophagu…
2007
Life history theory provides a powerful tool to study an organism's biology within an evolutionary framework. The notion that males face a longevity cost of competing for and displaying to females lies at the core of sexual selection theory. Likewise, recent game theory models of the evolution of ejaculation strategies assume that males face a trade-off between expenditure on the ejaculate and expenditure on gaining additional matings. Males of the dung beetle Onthophagus binodis adopt alternative reproductive tactics in which major males fight for and help provision females, and minor males sneak copulations with females that are guarded by major males. Minor males are always subject to sp…
Co-adaptation of pheromone production and behavioural responses in Drosophila melanogaster males
1999
0016-6723 (Print) Journal Article Research Support, Non-U.S. Gov't; In Drosophila melanogaster, male courtship behaviour is genetically controlled and is influenced by sex pheromones. 7-tricosene (7-T) induces a dose-dependent inhibition of male-male courtship, whereas 7,11-dienes stimulate male courtship of females. There is a geographical quantitative variation in the production of two predominant male hydrocarbons, 7-T and 7-pentacosene (7-P). We have previously found that 7-P, the main hydrocarbon from males of West African strains, stimulates males that mainly produce 7-T. Using both 'natural' and genetically engineered strains, we find that genetic factors coding for low levels of 7-P…
Is female-male mounting functional? An analysis of the temporal patterns of sexual behaviors in Japanese macaques
2019
Abstract In certain populations of Japanese macaques, adult females mount adult males in the context of heterosexual consortships (i.e., temporary but exclusive sexual associations between a male and a female). Previous research suggested that, in this primate species, female-male mounting (FMM) may be a behavioral adaptation. This functional hypothesis holds that FMM is a (special) courtship behaviour, or a (super) sexual solicitation, that serves the function of focusing the male's attention, preventing him from moving away, and expediting male-female mounting, in the context of high female competition for male mates. In this study, we aimed to test some of the proposed functional feature…