In many species that form socially monogamous pair bonds, a considerable proportion of the offspring is sired by extrapair males. This observation has remained a puzzle for evolutionary biologists: although mating outside the pair bond can obviously increase the offspring production of males, the benefits of such behavior to females are less clear, yet females are known to actively solicit extr...

Objectives: The purpose of current study was to determine the effect of Phaleria macrocarpa (P. macrocarpa)fruits aqueous extract on reproductive performance of adult male rats by assessing the serum testosterone level and evaluating their libido behavior. Methods and Materials: Eighteen male adult Spraque Dawley rats were divided into three groups and designated as treatment (240 mg/kg P. macr...

Mating behavior has profound consequences for two phenomena--individual reproductive success and the maintenance of species boundaries--that contribute to evolutionary processes. Studies of mating behavior in relation to individual reproductive success are common in many species, but studies of mating behavior in relation to genetic variation and species boundaries are less commonly conducted i...

Genetic polymorphisms are powerful model systems to study the maintenance of diversity in nature. In some systems, polymorphisms are limited to female coloration; these are thought to have arisen as a consequence of reducing male mating harassment, commonly resulting in negative frequency-dependent selection on female color morphs. One example is the damselfly Ischnura elegans, which shows thre...

In several primate species, females mate promiscuously and several adult males peacefully co-reside in the same social group. We investigated female mating behavior in two neighboring multimale-multifemale groups of Alouatta caraya in northern Argentina (27 degrees 20'S-58 degrees 40'W). All adult individuals in each group were marked with identification anklets and ear tags, and followed for f...

The adaptive significance of polyandry by female birds in the absence of direct benefits remains unclear. We determined the frequencies of polyandrous mating and multiple paternity in the ruff, a lekking shorebird with a genetic dimorphism in male mating behavior. More than half of female ruffs mate with, and have clutches fertilized by, more than one male. Individual females mate with males of...

Transitions from sexual to asexual reproduction provide a useful context for investigating the evolutionary loss of nonfunctional traits. It is often assumed that useless behaviors or structures will degrade, but this process is poorly understood. Potamopyrgus antipodarum is an ancestrally sexual New Zealand freshwater snail characterized by numerous independent transitions to asexual all-femal...

Internal fertilization without copulation or prolonged physical contact is a rare reproductive mode among vertebrates. In many newts (Salamandridae), the male deposits a spermatophore on the substrate in the water, which the female subsequently takes up with her cloaca. Because such an insemination requires intense coordination of both sexes, male newts have evolved a courtship display, essenti...

The accessory glands of male mosquitoes may produce substances that are transferred to females during mating and alter female physiology and behavior. The effects of male substances include the inhibition of subsequent female mating behavior, stimulation of oviposition and preoviposition behaviors, and the inhibition of host-seeking behavior. The circadian rhythmicity of females can also be alt...

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 (...