Understanding speciation hinges on understanding how reproductive barriers arise between incompletely isolated populations. Despite their crucial role in speciation, prezygotic barriers are relatively poorly understood and hard to predict. We use two closely related cricket species, Gryllus bimaculatus and G. campestris, to experimentally investigate premating barriers during three sequential m...

In traditional deterministic models the conditions for the evolution of sex and sexual behavior are limited because their benefits are context dependent. In novel and adverse environments both multiple mating and recombination can help generate gene combinations that allow for rapid adaptation. Mating frequency often increases in conditions in which recombination might be beneficial; therefore,...

Methamphetamine (Meth) users report having heightened sexual pleasure, numerous sexual partners, and engaging in unprotected sex due to loss of inhibitory control. This compulsive sexual behavior contributes to increased prevalence of sexually transmitted infections, but the neural basis for this is unknown. We previously established a paradigm for compulsive sexual behavior in male rats in whi...

Evidence from knockout studies in male mice and from experiments in male rats, in which expression of the estrogen receptor alpha (ERα) gene was inhibited in the medial preoptic area (MPO), suggests that ERα is important in the control of male rat mating behavior. Therefore, in this experiment, we tested the hypothesis that activation of ERα in the MPO is sufficient to maintain mating behavior ...

An alternative to classic sexual selection hypotheses for sex differentiated pre-mating behavior is that time available for mating-as individuals experience it-along with fitness differences among alternative potential mates, induces choosy versus indiscriminate mating behavior. This alternative hypothesis says that selection has acted so that all individuals flexibly express fitness-enhancing ...

Drosophila ananassae has a unique status among Drosophila species because of certain peculiarities in its genetic behavior. The most unusual feature of this species is its relatively high frequency of spontaneous male recombination. The results of studies on non-sexual behavior, such as phototactic responses, eclosion rhythm, and preferences for oviposition and pupation sites, lead us to sugges...

The genus Deroceras Rafinesque, 1820 (the largest genus of terrestrial slugs) shows a high diversity of penis morphologies and mating behaviors. The function of most of the appending external and internal penial structures, some of them truly bizarre, is largely unknown. This paper reviews mating behavior and reproduction, based on data on 16 species from the literature and from unpublished obs...

The effect of mating behavior on the expression of Fos protein was analyzed within the chemosensory pathways of the male Syrian hamster brain. Following a single mating test, the number of Fos-immunoreactive (Fos-ir) neurons increased within the amygdala, bed nucleus of the stria terminalis and medial preoptic area. The mating-induced pattern of Fos expression within these brain regions shows a...

INTRODUCTION One of the most important trade-offs for many animals is that between survival and reproduction. This is particularly apparent when mating increases the risk of predation, either by increasing conspicuousness, reducing mobility or inhibiting an individual's ability to detect predators. Individuals may mitigate the risk of predation by altering their reproductive behavior (e.g. incr...

effects of mating sex ratios on production performance in indian peafowl were investigated at punjabwildlife research institute, gatwala faisalabad. research was conducted from may through august 2007 toexplore the most productive mating sex ratio. the sex ratios have a significant effect on egg production.maximum mean eggs (1.63) were produced by the sex ratio 1:2 while maximum egg fertility (...