Copulins (in mammals)

Presumably, the affect is driven by increases in testosterone like those associated with copulins. It would have been great to disassociate the fecal connection from these odors, but this will not represent a problem for those who understand hormone metabolism.

My point is that it takes only a few active ingredients in the mixture, which means there are likely to be only a few copulins and only a few human pheromones. The relative concentrations of the pheromones  is important to their effect on hormones and their affect on behavior. Advertized “highest concentrations” of 6-12 “pheromones”  is not likely to equate with beneficial affects.

A mixture of odorant molecules potentially indicating oestrus in mammals elicits penile erections in male rats In Press, Uncorrected Proof, Available online 22 August 2011
Birte L. Nielsen, Nathalie Jerôme, Audrey Saint-Albin, Catherine Thonat, Christine Briant, Franck Boué, Olivier Rampin, Yves Maurin

Abstract

A common set of odorous molecules may indicate female receptiveness across species, as male rats display sexual arousal when exposed to the odour of oestrous faeces from rats, vixens and mares. More than 900 different compounds were identified by GC–MS analyses performed on faeces samples from di-oestrous and oestrous females and from males of the three species. Five carboxylic acids were found in lower concentrations in faeces from all oestrous females. We subjected 12 sexually trained male rats to a 30 min exposure to different dilutions of a mixture of these five molecules in the same proportions as found in female oestrous faeces. The behavioural responses of the rats were compared to those displayed when exposed to water (negative control) and faeces from oestrous female rats (positive control). Frequency of penile erections were found to be significantly dependent on mixture dilution, with two intermediate dilutions eliciting frequencies of penile erections that did not differ from those obtained during exposure to oestrous female rat faeces. Higher and lower dilutions did not elicit more penile erections than observed with water. These results support our hypothesis that a small set of odorous molecules may indicate sexual receptiveness in mammalian females.

Cosmetics: are they useful or do they just make us feel good?

Do we buy cosmetics because they are useful or because they make us feel good?

A study by the University of the Basque Country (UPV/EHU) shows that people who use cosmetics buy these products primarily for emotional reasons. The study was carried out on facial creams (hydrating and nutritive ones, coloured or non-coloured, and anti-wrinkle creams) and body creams (firming and anti-cellulite creams).

The full text of the research article is available for free: Women satisfaction with cosmetic brands: The role of dissatisfaction and hedonic brand benefits

Pheromone-enhanced behavior in sexually inexperienced females

Lack of sexual experience does not reduce the responses of LH, estrus or fertility in anestrous goats exposed to sexually active males.

“These results strongly suggest that the sexual physiological state of males is critical to obtain a high response of females exposed to males, overcoming the lack of sexual experience. It seems that the high sexual behavior displayed by males and the high olfactory cues provided (Delgadilo et al., 2002; Rivas-Muñoz et al., 2007; Vielma et al., 2009), enhanced female’s response even in sexually inexperienced ones.”

In my model: An evolved GnRH-driven neurophysiological mechanism that is driven by pheromones during development primes and subsequently drives the LH response, which is associated with behavior. That explanation seems more likely than an automagical response to visual input from the males. Besides, there is no model for how women develop their differences in preferences for the visually appealing physical features of men — unless visual appeal is directly associated with olfactory/pheromonal input.

That explains how we could predict changes in women’s flirtatious behavior after exposure to a mixture of human pheromones.  So, we ignored the differences between women and other female animals and focused on their biologically based similarities.  Androstenol, for example, is known to alter levels of LH in women. Thus, all we needed was a species specific component of the mixture that signaled masculinity to women in the same way masculinity was signaled by the male goats (via its association with levels of androgens, like testosterone).

We’re rather certain that this is what androsterone does, and it explains what we observed: increased flirtatious behavior. I was still somewhat surprised that the women reported they were more attracted to the man when he was wearing the androsterone/androstenol mix. But only because I didn’t think they would notice any increased attraction.

Typically, the behavioral affect is not perceived, so it makes sense that women were not aware of any increased attraction due to the pheromones. Instead, they merely reported on a questionnaire that they were more attracted to the man when he was wearing the mixture (i.e., an unconscious affect).

The Mind’s Eyes: Mindful modeling of brain directed behavior

Some people think that certain aspects of human behavior are difficult or impossible to model in other animals. To me, this indicates what’s wrong with behavioral science. Is it science if we can’t infer anything about causality from other species?  Clearly, the molecular biology of all species is the same. Why not use molecular biology as the basis for the examination of behavior across species?

An ontogenetic and phylogenetic perspective shows that principles of biology and levels of biological organization constrain the link between sensory input and behavior. The link must involve one or more steps in a gene-cell-tissue-organ-organ system pathway that links sensory input to behavior. For example, single-celled organisms have genes in cells (i.e., two steps of a five-step pathway in mammals) but they do not exhibit any complex system-driven behavior. Compared to mammals, single-celled organisms lack the required tissue in the organs of an organ system like the mammalian central nervous system (CNS).

The mammalian CNS can only allow for biologically constrained behaviors. But, with the evolutionary advent of tissue in organs of the organ system that directs brain-based behavior (i.e., the CNS), behavior is less constrained. Thus, evolutionary biology allows for more diverse behaviors across species.

Language, culture and “free will” do not exist outside biological constraints. This suggests that even the complex mind of a human being can be modeled within the biological constraints of the brain. We may not yet know enough to completely detail an animal model of the mind, but we have certainly made some progress towards modeling “the mind’s eyes.” That progress came with the understanding that visual input cannot be directly linked to behavior via a gene-cell-tissue-organ-organ system pathway in any animal.

We owe a lot of the perceived mind-brain dualism to thoughts about what drives our behavior, but what we think does not matter.  What we see does not drive our behavior, and neither does what we say or hear. Tactile sensation may activate reflexes, but reflexes are not brain-based behavior. Instead, the chemical senses drive the behavior of all species, and the molecular mechanisms that allow this are modeled in other species – all of them.

Food odors drive behaviors associated with food acquisition; social odors drive behaviors associated with mate acquisition. Responses to food and to potential mates are conditioned to occur in the presence of other sensory input, like what we see or hear. But visual and auditory input is not required as part of the biology of behavior.

Odors activate genes in cells of tissue in the mammalian brain, and odors drive the behavior of all species.

Juvenile play conditions sexual partner preference in adult female rats Original Research Article
Physiology & Behavior, In Press, Accepted Manuscript, Available online 14 July 2011
Pedro Paredes-Ramos, Marta Miquel, Jorge Manzo, Genaro A. Coria-Avila

Highlights

► Neutral odors paired with juvenile play induce an olfactory conditioned play partner preference in prepubescent female rats ► The same conditioned odors (CS+) induce conditioned sexual partner preference in adult female rats. ► Sexual partner preference is observed with more proceptive behaviors directed towards the CS + male, which responds with more mounts, intromissions and ejaculations. ► This conditioned preference may be strong enough to support assortative mating.

See also: The Mind’s Eyes: Human pheromones, neuroscience, and male sexual preferences

Epigenetic ‘memory’ key to nature versus nurture

Researchers have made a discovery that explains how an organism can create a biological memory of some variable condition, such as quality of nutrition or temperature. The discovery explains the mechanism of this memory — a sort of biological switch — and how it can also be inherited by offspring. - ScienceDaily (2011-07-25)

Click on the link to this article and you should see pictures of bees on flowers. Although there is no mention of their significance, which may be unknown to the journalist, the pictures link honeybees to flowers, food odors, and social odors (called pheromones)  in a manner that is now becoming understood. Simply put, the molecular biology of chemical communication is the same across all species from plants to animals. Their genetic “nature” is influenced by stimuli from the environment. Chemical stimuli are more important than any other form of sensory stimuli in this regard. Whether the chemicals are associated with pollen and the bee-assisted reproduction of flowers; the human cultivation of plants with enticing food odors, or the pheromones associated with reproduction in all animal species, the epigenetic influence of these chemicals is obviously the most important of all to species survival.