Chromosomal rearrangements between sympatric species often contain multiple loci contributing to assortative mating, local adaptation and hybrid sterility. When and how these associations arise during the process of speciation remains a subject of debate. Here, we address the relative roles of local adaptation and assortative mating on the dynamics of rearrangement evolution by studying how a r...

The main goal of this study was to test the effectiveness of two molecules of pheromones identified in the urine of cows in estrus at stimulating sexual function and increasing reproductive capacity of bulls. The trial lasted four weeks and the bulls were divided into two groups (experimental and control) with ten bulls. For this experiment we used an intranasal spray comprising the pheromone m...

We have shown that the Sex-lethal (Sxl) gene, which controls morphological aspects of sex determination in Drosophila melanogaster, also regulates sexual behavior. Chromosomal males that are hemizygous for a deletion of the entire Sxl locus perform normal courtship and synthesize the two courtship-inhibiting pheromones that normal males make. However, ectopic expression of female-specific Sex-l...

In the fission yeast Schizosaccharomyces pombe, the onset of sexual development is controlled mainly by two external signals, nutrient starvation and mating pheromone availability. We have isolated a novel gene named rcd1+ as a key factor required for nitrogen starvation-induced sexual development. rcd1+ encodes a 283-amino-acid protein with no particular motifs. However, genes highly homologou...

Sexual dimorphism in the distribution of antennal sense organs is common among adults of the genus Periplaneta. In three out of the four strains of Periplaneta americana examined, adult males had more contact chemoreceptros than females. In the fourth strain of P. americana and in P. australasiae, P. brunnea, P. fuliginosa, and P. japonica, no statistically supportable sexual dimorphism of cont...

Male-specific fruitless (fru) products (Fru(M)) are both necessary and sufficient to "hardwire" the potential for male courtship behavior into the Drosophila nervous system. Fru(M) is expressed in approximately 2% of neurons in the male nervous system, but not in the female. We have targeted the insertion of GAL4 into the fru locus, allowing us to visualize and manipulate the Fru(M)-expressing ...

Male nematodes secrete pheromones that accelerate the somatic senescence of potential mates. A new study shows that this harm most likely is an unintended by-product of the males' aim to speed up sexual maturation and delay reproductive senescence of future partners.

The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whethe...

The E and Z pheromone strains of the European corn borer (ECB) provide an exceptional model system for examining the genetic basis of sexual isolation. Differences at two major genes account for variation in female pheromone production and male behavioral response, components of the pheromone communication system known to be important for mate recognition and mate choice. Strains of ECB are mor...

Many mammalian species utilize chemical signals, commonly termed pheromone, for social and sexual communication between the same species via the vomeronasal organ (VNO). VNO-ablated or genetically modified mice showed behavioral impairments, providing strong evidence that pheromones are detected by VNO (Wysocki and Lepri, 1991; Del Punta et al., 2002; Loconto et al., 2003; Norlin et al., 2003)....