Masturbation and nocturnal emissions--possible mechanisms for minimising teratozoospermie and hyperpermie in man

Spontaneous nocturnal erections and masturbation in captive male chimpanzees (Pan troglodytes)

Nocturnal penile tumescence (NPT) has been reported for males of only a few mammalian species, including humans, albeit this scarcity might be an artefact of the difficulty of documenting it. We investigated NPT in 12 adult male chimpanzees living in an all-male group at Kumamoto Sanctuary, Japan. Recorded non-invasively with infrared video cameras across 72 nights (6 per individual), we observed NPT in two thirds of the individuals (8/12), with events in total. More than three quarters occurred during a transition from sleep to wakefulness, suggesting NPT may be associated with rapid eye movement sleep, similar to humans. Masturbation occurred in conjunction with NPT, including the likely consumption of ejaculate, in 4–6 individuals. While detailing nocturnal erections in chimpanzees may help us to better understand this robust physiological phenomenon in humans, further comparative research is necessary to reconstruct its phylogenetic history. At present, our findings support hypothetical functional explanations such as the facilitation of nocturnal emissions in order to increase ejaculate quality or an increase in tissue oxygenation to prevent erectile dysfunction.

The First Ejaculation: A Male Pubertal Milestone Comparable to Menarche?

Boys experience their first ejaculation (thorarche) during adolescence, but this event is often overlooked as a milestone in male adolescent development. The purpose of this article is to draw attention to thorarche and consider it in comparison with the female milestone of menarche. A critical analysis is provided of how thorarche has been interpreted to date and the complexities in construing thorarche from a biological perspective are outlined. Despite potential tenability of characterizing thorarche as a comparable milestone to menarche, two particular points challenge this notion: (a) While thorarche may befall the boy involuntarily, it may also be induced by the boy's own will; and (b) Thorarche occurs concomitantly with (pubertal) orgasmarche and has an innate connection with sexuality. The answer to the title question remains contentious, but open topics for future research are noted throughout the article as essential steps towards attaining a better understanding of thorarche.

Spontaneous ejaculation in a wild Indo-Pacific bottlenose dolphin (Tursiops aduncus)

Spontaneous ejaculation, which is defined as the release of seminal fluids without apparent sexual stimulation, has been documented in boreoeutherian mammals. Here we report spontaneous ejaculation in a wild Indo-Pacific bottlenose dolphin (Tursiops aduncus), and present a video of this rare behavior. This is the first report of spontaneous ejaculation by an aquatic mammal, and the first video of this behavior in animals to be published in a scientific journal.

First stirrings: cultural notes on orgasm, ejaculation, and wet dreams

Both the findings and the limitations of numeric milestone research in sexology have a bearing on the pedagogical status of pleasure, as well as the cultural underpinnings of the notion of a psychosexual milestone. An overview is offered of international data pertaining to the chronology of three "milestones" in sexual autobiography: first orgasm (orgasmarche), first ejaculation (oigarche), and first wet dream (nocturnal emission). Methodological problems associated with the measurement of these variables are discussed. These problems are then situated in a culturalist perspective. It is concluded that orgasms are cultural artifacts in terms of their chronological occurrence as well as perceived salience, necessity, and "age appropriateness".