Pardon Me, Do You Have Any Mouse Poupon?

Here’s a tasty new offering from researchers at the Centre des Sciences du Goût et de L’Alimentation in Dijon, France: “Male mice and cows perceive human emotional chemosignals: a preliminary study.”

How do you know if a mouse is perceiving chemosignals of human fear? It poops out more fecal pellets.

How do you know if a cow prefers chemosignals from nonstressed humans? It spends more time smelling the bucket that contains them.

How do you obtain these wondrous human chemosignals? The old cotton pads in the underarms gambit. You get some engineering students to abstain from stinky food and perfume for a few days (major sacrifice—this is France, after all) and wear the pads during a regular class (non-stress) and during an exam (stress).

What can I say? I admire the weirdness of the experimental design. I wonder if members of the ethics panel of the French Ministry of Higher Education and Research managed to keep a straight face during the review meeting.

Sidebar: The title of the paper mentions “male mice” and “cows,” when in fact the animals used were male mice and nulliparous female bovines. Shit-kicking American readers would expect “male mice and heifers,” but evidently the heifer vs cow distinction isn’t recognized in the editorial offices of Animal Cognition.

And finally, with apologies to the man from Nantucket:

There once was a heifer from Dijon,
Whose nostrils scientists seized on,
She found it a balm,
When the students smelled calm,
And the researchers gained a citation.

The study discussed here is “Male mice and cows perceive human emotional chemosignals: a preliminary study,” by Alexandra Destrez, Morgane Costes‑Thiré, Anne‑Sophie Viart, Floriane Prost, Bruno Patris and Benoist Schaal, published online in Animal Cognition, April 11, 2021.

Human Pheromones: Abandoned by the Wayside

The great intellectual wagon train of behavioral science rolls on, leaving behind heaps of junk that the scientific pioneers no longer find useful. Miles back there’s a big pile of specialized “instincts” for this and “drives” for that. Further up, the trail is strewn with Skinner boxes and the shabby wreckage of behaviorism. In the near distance are items more recently jettisoned: the excess baggage of mammalian pheromones.

Georgia State researcher Aras Petrulis is the latest to toss the pheromone concept to the side of the road. In a review article to appear soon in the journal Hormones and Behavior, he examines “chemosignals, hormones and mammalian reproduction.” His conclusions echo those of Richard Doty.

Petrulis doesn’t deny the importance of smell. In his view, “it is clear that social odors play a substantial and oftentimes obligatory role in mammalian reproduction.” However, he believes that the actions of these social odors rarely meet the definition of a pheromone. Why?

The role of learning and memory in the behavioral and physiological responses to opposite-sex conspecifics is generally under-appreciated by the non-specialist. [Don’t be offended, FN readers! Dr. Petrulis’s condescension is directed toward other PhDs—those outside his narrow discipline.] Many of the reproductive effects reviewed above are clearly subject to learning in adulthood as evidenced by their dependency on sexual experience or prior contact with chemosignals as well as by their ability to be conditioned to previously neutral odors.

This dependence on learning and context undercuts the most fundamental idea of a pheromone; that is, that responses to it are “instinctual” and therefore not learned. Similarly, the fact that most chemosignals altering mammalian behavior and/or physiology are complex mixtures often lacking species-specificity, rather than being potent and essential singular compounds, further erodes the utility of the term “pheromone”. Because of these concerns, it is perhaps wise to restrict the term to molecules that have met each and every criterion of a pheromone, as used in the classical ethological sense.[Emphasis mine.]

And if we restrict the term as he so gingerly suggests, where does that leave us with respect to human pheromones?

Lastly, it should be clear that chemosignals are neither necessary nor sufficient for human reproduction nor do they have a privileged place in directing human social behavior. Positive findings of human chemical communication, when not based on flawed analysis . . . are often inconsistent, and at best, demonstrate modest effects on human behavior and physiology.

So take it from a guy who studies sex behavior for living: drop the human pheromones and lighten your load.

The study discussed here is “Chemosignals, hormones and mammalian reproduction,” by Aras Petrulis, published online in Hormones and Behavior, March 29, 2013.

Coming Attractions: Sperm Wars—The Bourgeonal Strikes Back

 ..

Earlier this year I declared that the Bourgeonal Sperm Wars were over. Now it seems that announcement may have been a bit . . . premature.

The Prequel
Bourgeonal, which smells like lily of the valley, activates the OR1D2 olfactory receptor found in the human nose and on human sperm cells. Bourgeonal is also the only odorant to which men are more sensitive than are women, and sperm respond to it as well. This led some researchers to suggest that bourgeonal is a chemosignal that guides sperm to the egg.

However, Timo Strünker and colleagues demonstrated that the CatSper Ca2+ ion channel, the molecular mechanism which triggers the relevant behavioral changes in sperm, is activated not only by bourgeonal but by steroids, prostaglandins, menthol, and helional (everything but the kitchen sink). As a finishing touch, Strünker et al. found that the OR1D2 receptor itself is not necessary for bourgeonal to activate the CatSper channel. So much for the notion of sperm tracking the egg by lily of the valley scent.

The New Releases
Now come two papers linking olfactory perception of bourgeonal to human infertility. The first is by olfaction researcher Thomas Hummel and colleagues at the University of Dresden Medical School. They gave smell tests to men with idiopathic infertility, i.e., guys from couples trying unsuccessfully for two years to get pregnant in the absence of a medical cause. The infertile guys were compared to proven fathers of similar age.

The groups did not differ in overall smell ability, or in sensitivity (detection threshold) to bourgeonal and a couple of other floral scents: helional and phenylethyl alcohol. However, infertile guys perceived the odor of bourgeonal as significantly less intense at above-threshold concentrations. The perceived the other two scents the same as the fertile guys. According to Hummel et al., decreased olfactory sensitivity to bourgeonal may relate “to a decreased functionality of OR1D2, which in turn may be linked to idiopathic infertility.”

I know what you’re thinking: this is a slender thread on which to hang the bourgeonal story. But the same week, a paper by an Italian research group at the University of Padua came up with a finding that took the story even further.

Led by Giancarlo Ottaviano, the group compared a group of infertile men to a set of healthy controls. The infertile guys were significantly less sensitive to the odor of bourgeonal (detection threshold), and their sperm were significantly less likely to migrate in the direction of bourgeonal. Genetic analysis of the OR1D2 receptor showed that single nucleotide polymorphisms (tiny genetic mutations) were more common among the infertile men. The Padua team believes they have confirmed the importance of olfactory receptor-based bourgeonal detection in human male infertility.

The Review
Based on the Strünker papers I thought the sperm-guided-by-bourgeonal idea was probably an artifact. However, these new findings are not easy to dismiss. It looks like there will be more episodes of Sperm Wars in the future.

The studies discussed here are “Decreased perception of bourgeonal may be linked to male idiopathic infertility,” by Charlott Sinding, Eva Kemper, Petra Spornraft-Ragaller, and Thomas Hummel, published online in Chemical Senses, March 27, 2013, and “Human olfactory sensitivity for bourgeonal and male infertility: a preliminary investigation,” by Giancarlo Ottaviano, D. Zuccarello, M. Menegazzo, L. Perilli, G. Marioni, A.C. Frigo, A. Staffieri, and C. Foresta, published online in European Archives of Otorhinolaryngology, March, 2013.

Riskay Business? Receptors Specialized for Social Smells

Image from Wallrabenstein, et al., 2013

Linda Buck and Richard Axel transformed the study of smell with their Nobel Prize-winning discovery of the mammalian olfactory receptor (OR) genes in 1991. These genes code for a diverse set of cell-surface receptors expressed on the surface of sensory cells in the nose. Receptor diversity enables the detection of a broad array of odor molecules. With as many as 1,500 varieties, the OR gene family is the biggest in the human genome—testimony to the evolutionary importance of odor perception. OR genes create a type of receptor structure that elsewhere in the body figures in the detection of sex hormones and neurotransmitters.

In 2006, Stephen Liberles and Linda Buck found a second class of chemosensory receptors in the nose of humans, mice and fish. It consists of a handful of receptors (six to fifteen, depending on that species) that are structurally unrelated to ORs. Instead, they look like the receptors for biogenic amines, e.g., the neurotransmitters serotonin and dopamine. The new class was dubbed “trace amine-associated receptors” or TAARs because they are exquisitely sensitive to a specific class of molecule—volatile amines—that turns out to be common in mouse urine. Thereby hangs a tale.

Given the affinity of TAARs for the smelly amines in mouse piss, Liberles and Buck speculated that these receptors play a role in social behavior. This isn’t as crazy as it sounds—mice send all sorts of social messages via chemical cues in their urine. This January, Liberles and a team of colleagues advanced the story in much greater detail. They focused on one TAAR receptor which, in an odd resonance for perfume fans, is called TAAR5. It is especially sensitive at detecting trimethylamine (TMA), a molecule famous for having exactly the stink of rotting fish.

But for one enzyme, human urine would also smell of dead fish, since bacteria in our gut turn the choline in food into obnoxious TMA. Thankfully, almost everybody produces the flavin-containing monooxygenase 3 enzyme (FMO3), which chemically converts TMA to a non-smelly molecule. Those few unfortunates born with a defective FMO3 gene suffer from “fish odor syndrome,” and must modify their diet to avoid the stinky stigma.

Meanwhile, male mice have a ton of TMA in their urine while females have almost none. And while the odor of TMA at high levels is aversive to mice, it is attractive to both sexes at the concentrations found in urine. So what’s going on? Liberles et al. found that female mice produce the FMO3 enzyme which keeps TMA out of their pee. Males stop producing FMO3 at puberty and thus have TMA-stinky pee. Genetically controlled production of TMA, coupled with a preference for its odor, seems to occur only in the house mouse Mus musculus and not in other members of the genus Mus or other rodents such as rats. Liberles et al. speculate this synchronous evolution of odor biosynthesis plus behavioral response has something to do with signaling species identity. Research on a variety of rodents species is needed to see if the idea bears out.

In February, Thomas Bozza’s team at Northwestern used a variety of techniques to examine the functional sensory response of TAAR-expressing sensory cells. They conclude that TAARs “serve as high-affinity amine detectors in mammalian olfactory systems.” While TAARs are broadly tuned to detect amines, one in particular (TAAR4) is “exquisitely sensitive” to β-phenylethylamine—so much so that it rivals “the most sensitive mammalian chemosensory neurons yet examined.” And what is β-phenylethylamine? It’s a chemical found in the urine (and therefore scent marks) of carnivorous predators. Not a bad thing to be sensitive to if you’re a prey species like the mouse.

So what of the six human TAARs? Do these receptors make us exquisitely sensitive to TMA or β-phenylethylamine or other biologically relevant amines? Two TAARs are known to be expressed in the human nose. Bozza et al. expressed the human hTAAR5 gene in mouse sensory cells and found that it responds to N,N-dimethylethylamine and somewhat less to TMA.

Finally, also in February, a German team led by Ivonne Wallrabenstein expressed human hTAAR5 in animal cells and measured the receptor’s response to a wide variety of amines (pictured at the top of this post). The human TAAR5 receptor is highly and specifically sensitive to TMA and less so to dimethylethylamine (the two molecules in the shaded portion of the picture). You don’t have to be a specialist to get the gist of the results:



(The big response is TMA; the third response from the left is dimethylethylamine.)

Of what use is a specialized human ability to detect TMA? Wallrabenstein et al. note that besides being found in rotting fish, “TMA arises in rotting male ejaculate and vaginal secretions.” Yes, well . . . there’s that. But is TMA sensitivity simply an evolved reminder to wash after use? My hunch is that it’s more than that—possibly a means of detecting out-of-pair-bond copulation, or what in a less politically correct time we used to refer to as sneaky fucking.

Why u comin home 5 in the mornin
Somethins goin on, can I smell yo dick 

                   --Riskay (2007)

Social smell signals, indeed.

The studies discussed here are “A second class of chemosensory receptors in the olfactory epithelium” by Stephen D. Liberles and Linda B. Buck, published in Nature 442:645-650, 2006; “Synchronous evolution of an odor biosynthesis pathway and behavioral response” by Qian Li, Wayne J. Korzan, David M. Ferrero, Rui B. Chang, Dheeraj S. Roy, Mélanie Buchi, Jamie K. Lemon, Angeldeep W. Kaur, Lisa Stowers, Markus Fendt, and Stephen D. Liberles, published in Current Biology 23:11-20, 2013; “Ultrasensitive detection of amines by a trace amine-associated receptor” by Jingji Zhang, Rodrigo Pacifico, Dillon Cawley, Paul Feinstein, and Thomas Bozza, published in Journal of Neuroscience 33:3228-3239, 2013; and “Human trace amine-associated receptor TAAR5 can be activated by trimethylamine,” by Ivonne Wallrabenstein, Jonas Kuklan, Lea Weber, Sandra Zborala, Markus Werner, Janine Altmüller, Christian Becker, Anna Schmidt, Hans Hatt, Thomas Hummel, and Günter Gisselmann, published in PLoS One 8:e54950, 2013.

Sperm Wars: Lily of the Valley Revisited

One of the stranger stories in olfactory science is the apparent ability of mammalian sperm to respond to the odorant bourgeonal, which to the human nose smells somewhat like lily of the valley. Speculation has been that this pleasant floral scent is also a secret signaling molecule that guides sperm to the egg, by activating the odorant receptor OR1D2 located on the sperm cell’s surface.

Adding to the strangeness is the fact that, unique among odorants that have been tested, men are more sensitive to bourgeonal than are women. Men more sensitive to bourgeonal, sperm able to detect it—there seemed to be a compelling narrative.

Now it appears that the entire lily of the valley story needs to be rewritten.

Back in 2011, researchers led by Timo Strünker at the Center of Advanced European Studies and Research, in Bonn, Germany, took a closer look at the biochemistry of sperm, specifically at the mechanism underlying the progesterone-induced calcium ion (Ca2+) influx. The calcium influx activates a number of key physiological responses in sperm, including chemotaxis. The thought had been that a cell-surface receptor activated by progesterone kicked off a series of biochemical reactions leading to the opening of the CatSper Ca2+ ion channel. Once the channel is open, calcium ions flood through and into the sperm cell.

What Strünker and his colleagues demonstrated in their paper in Nature is that the CatSper channel is not opened by activation of a separate progesterone receptor. Instead, the CatSper channel itself (or an associated protein) serves as the progesterone receptor. (To anthropomorphize a bit: if you a progesterone molecule, you hold the key that opens the door directly; you don’t need to ring a doorbell down the hall and have someone open the door for you from the inside.)

While of interest mostly to biochemists, the Nature paper was a warning shot over the bow of Team Bourgeonal. It meant that separate, specialized receptors, such as odorant receptors, were not necessary for the calcium influx. In 2012, Strünker and team fired directly amidships. In an intricate and exhaustive set of experiments, they showed that the CatSper channel is activated by all sorts of molecules, including steroids, prostaglandins, menthol, bourgeonal, and several other odorants such as cyclamal, helional, and undecanal.

In other words, you can activate the CatSper channel by looking crooked at it. Or, as the researchers put it, “Activation happens through promiscuous, extracellularly accessible site(s) either on the channel itself or on associated proteins.” And this activation takes place completely independent of any odorant receptor for bourgeonal.

Team Strünker hypothesizes that the promiscuous CatSper channel “serves as a polymodal sensor for multiple chemical cues that assist sperm during their voyage across the female genital tract.” The idea that sperm are specifically attracted to bourgeonal’s lily of the valley scent is, it seems to me, dead in the water.

The studies discussed here are “The CatSper channel mediates progesterone-induced Ca2+ influx in human sperm,” by Timo Strünker, Normann Goodwin, Christoph Brenker, Nachiket D. Kashikar, Ingo Weyand, Reinhard Seifert, and U. Benjamin Kaupp, published in Nature 471:382-386, 2011, and “The CatSper channel: a polymodal chemosensor in human sperm,” by Christoph Brenker, Normann Goodwin, Ingo Weyand, Nachiket D. Kashikar, Masahiro Naruse, Miriam Krähling, Astrid Müller, U. Benjamin Kaupp, and Timo Strünker, published in EMBO Journal, 31:1654-1665, 2012.

Olfactory Tips from the Free Clinic

So you’ve exchanged a few text messages with that guy you met on VeganSingles.com, you’ve carefully chosen an outfit that’s alluring yet not Jersey Shore-ish, and you’re heading out the door for your first face-to-face, hoping for the best.

Remember one thing: get a good sniff of Mr. Eligible before taking things to the next level.

That’s the net-net from a new paper in the Journal of Sexual Medicine. Extending to humans a finding that has been well established in rats and mice, a team of Russian scientists has found that guys battling an infectious disease smell, uh, somewhat “putrid” in the armpits. And since the disease in question is gonorrhea, rank BO is another thing to watch for, along with whether he pays for the drinks and holds the door.

Mikhail Moshkin and colleagues from scientific institutes in chilly Siberia used the now-classic cotton-pads-pinned-into-T-shirts technique to collect axillary odor from young men. The odor donors included guys with current gonorrhea infection, guys cured of same, and guys who were never infected. A group of young women rated the BO samples for strength and pleasantness, and described them using a list of adjectives.

The results in a nutshell: infectious disease reduces a person’s odor attractiveness, and

The odor of infected persons was more often associated with a putrid smell. The odor of recovered persons was more often associated with a floral smell.

Moshkin et al. observed the usual experimental niceties: the odor donors refrained from eating spicy food for two days before the study, the odor judges did not use hormonal contraceptives, and the BO samples were stored at -20°C. The judge’s menstrual cycle phase made no difference to the outcome.

Saliva sample from the male odor donors were analyzed for testosterone, cortisol, and immunoglobulins A and G. None of these measures differed significantly among the three test groups. However,

while salivary IgA and IgG concentrations were insignificantly higher in the infected persons, they correlated negatively with pleasantness scores and positively with prevalence of putrid associations. A high level of the nonspecific salivary immunoglobulins reflects activation of the defensive mechanisms due to general antigenic pressure on the immune system. Several studies on laboratory animals demonstrate that antigen-induced immunoenhancement leads to reduction of male scent attractiveness.

Another small victory for the human sense of smell. Forget about electronic noses, trained service dogs, or hacking into private medical records. Just use your nose.

The study discussed here is “Scent recognition of infected status in humans,” by Mikhail Moshkin, Nadezhda Litvinova, Ekaterina A. Litvinova, Alena Bedareva, Andrey Lutsyuk, and Ludmilla Gerlinskaya, published in the Journal of Sexual Medicine, ahead of print, on December 6, 2011.

Sex Pheromones by the Numbers: Have They Peaked?

I recently declared that I no longer find the concept of human pheromones to be scientifically useful. I think there is lots of evidence for the effect of scents on human cognition, behavior, and physiology. But if we insist on labeling all these various effects as pheromones, we muddy the intellectual waters and make it harder to understand the biological basis of the effects. Dick Doty, in his book The Great Pheromone Myth, has done an impeccable job of showing how intellectually bankrupt the pheromone concept has become.

Still, there are die-hards out there who believe that with enough gas chromatography-mass spectrometry and with fine-grained enough fractionations, they will isolate the magic molecule that Will Drive Women Wild. Their more restrained colleagues believe that more research may lead to a mixture of a few different molecules that, when applied to a female with a specific mating history, at a specific time of the month, may, under certain specified conditions, alter her perception of men. For them, sex pheromones are a mixture that Will Drive Women to a Statistically Significant Difference in Perception.

Not exactly the stuff of lurid fantasies . . .

My sense is that many scientists in the field privately agree with Doty’s critique; it’s just not politic to trash the concept when you are applying for grant funding to study sex and scent.

It’s also my sense that public enthusiasm for pheromones has cooled. To test my impression, I played with a program from Google Labs:

When you enter phrases into the Google Books Ngram Viewer, it displays a graph showing how those phrases have occurred in a corpus of books (e.g., “British English”, “English Fiction”, “French”) over the selected years.

Neato! So let’s enter “pheromone” and ask for results from the corpus of English books from 1950 to 2008. Here’s what we get:



We find that pheromone enters the charts soon after its coinage in 1959, and climbs steadily to a peak in 2000. After that, it’s all downhill.

Can such a widely credited concept go bust just like that?

In my review of Doty’s book I wrote:

Once upon a time instinct theory was equally in vogue and used to “explain” all sorts of behavior. Today it’s rarely invoked. By specifying the roles of context and learning, behavioral science simply outgrew the need to appeal to instinct.

So let’s put “instinct” in the Google Ngram Viewer, set the time frame for 1800 to 2008, and see what we get.



Interesting! Instinct enjoyed a long climb in usage throughout the 19th Century and into the first two decades of the 20th. (Darwin, Freud, yadda yadda.) But it peaked in 1921 and then sank like a stone.

Which leads one to wonder: was 2000 the high water mark for pheromones? My money says yes.

The Transparency of Human Sex Pheromones

It looks like the emperor-has-no-clothes pushback against the concept of human sex pheromones is getting some traction in the popular press. Susan Perry, in a post at MinnPost.com, is exceptionally blunt: “Our body odors are not subliminal mating signals.” She highlights an article in Slate by Randi Hutter Epstein subtitled “Don’t trust the hype about pheromones and sexual attraction.”

Epstein’s piece spurred a raucous series of comments, including several by the tireless James V. Kohl, for whom it seems that every piece of evidence for human chemical communication is proof that the pheromone concept as brought forth in 1959 is true in its entirety and completely applicable to humans.

Perry’s piece also features a James V. Komment, which boils down to “Check out my poster about the emperor’s button: obvs he’s wearing the most beautiful, triple-stitched, silk-lined, fur-collared robe evah.”

Surprisingly, JVK is upstaged by Ross (aka Bubba) Nicholson who comment spams his latest publication, Exocrinology: The Science of Love, 2nd Edition; Human Pheromones in Criminology, Psychiatry, and Medicine.

The book’s Kindle product description from Amazon makes some startling claims:

Exocrinology The Science of Love Human Pheromones in Criminology, Psychiatry, and Medicine describes human chemical ecology, the physiology of kissing and hugging, and the passing of human pheromones to explain criminology, psychiatry, addiction pathology and pheromonal sexual orientation. The book begins with home remedies for juvenile delinquency, puberal running away, heroin and cocaine addiction, and unwanted sexual deviancies. The remedy has allowed Charlie Sheen and his Hollywood colleagues to break clear of addiction and perversion. Ellen Page of Inception and Juno fame, is now entirely heterosexual, as are Jessica Simpson and Leelee Sobieski who were earlier recipients.

Exocrinology’s epigenetic pheromones provide explanation for most of the rest of human pathology. The autoimmune disease signs and symptoms find a coherent systematic elucidation, with recommended pheromone therapies for remediation.

This day will be long remembered. Publication of Exocrinology The Science of Love will mark the emergence of modern medicine from the dark ages of psychological catastrophe and the beginning of a new era for humanity.

This book’s power to cure criminal behavior alone will provide trillions of dollars in economic benefit to humanity. Human pheromones provide the final epigenetic key to the medical puzzles of human behavior, physical and mental illness. Pheromones, their deficiencies, receptions, and excesses, accommodate the synthesis of economic, neuroanatomical, physiological, chemical, and behavioral evidence into a new theory of sociopathy and disease: the pheromone theory of love and illness. Surely this book will irrevocably revolutionize human social organization. We must use this new knowledge wisely and well. This is a book of genius. This is a book for the ages.

So who is the author of this book of genius? Here’s the About the Author section from the paperback edition of similar Nicholson opus:

Bubba Nicholson (1954-present) is the ultimate insider. As a teenager, he was instrumental in the decisions of three US Presidents to run for the office. He invented the modern meaning of the word Inclusive and the concept of inclusive democracy. He conceived the Deadbeat Dad Laws that found a state interest in enforcing alimony and child support. Nicholson proposed The HOPE Scholarships that lifted Georgia into the 21st century, with college education for millions of people. It was Nicholson who insisted Spielberg film E.T. and Schindler’s List and it was his idea to film Star Wars. He created and wrote the stories for Avatar, Titanic, Inception, Forrest Gump, The Matrix, and dozens more. Those are his speeches in Braveheart, Juno, and 300. Aside from the $1 and microcassettes for the saxophone cave solo (originally flute) in Dead Poets Society, Nicholson never took compensation for helping Hollywood, citing its ill effect on creativity. Now Nicholson’s great scientific genius is brought to bear on the greatest social and medical problems of our time. “This is why I went to medical school! Hotcho Momma!”

Mr. Nicholson should tell his publicist to take it down a notch. Then again, the rhetoric is consistent with Nicholson’s own approach to establishing authorial credibility. In the Preface to the first edition of Exocrinology, Nicholson explains why his views haven’t yet achieved the scientific renown they deserve. It is due to his “Spielberg show business association” (above) and his “youthful political associations.”

My helps to successful politicians (e.g. the Bushes (villainous fiends who murdered JFK, MLK, RFK, LBJ, George Wallace and many more), the Clintons, Julian Bond, Zell Miller, Ann Richards, Strobe Talbot, Khalid Sheikh Mohammed: “Privatization”, “Deadbeat Dad Laws”, “Inclusive Democracy”, “HOPE Scholarships”, “Freedom of Religion Rules in the Federal Workplace” have helped our country, but serve only to disparage me among the various science tribes.

Damn those intolerant science tribes. Mr. Nicholson sounds just like the trusted authority we need to spread the word about human sebum being the cure for crime and lesbianism. What else can he shed light upon?

The JFK assassination and almost all following American assassinations were conducted to appease Barbara Bush’s sexual lusts. [I knew it!—Ed.] Her vengeful husband, the cuckold George H.W. Bush, carried it off.

I recall meeting Bubba Nicholson when I worked at the Monell Chemical Senses Center in the last century. He had a notion about kissing being a behavioral mechanism for transferring behavior-activating sebum from one person to another. Plausible. But no way am I buying that crap about Strobe Talbot.

[Hat tip to FN reader Steve S.]

Family Feud: Gilbert vs. Vosshall on Human Sex Pheromones

Here’s a video snippet of the World Science Festival smell panel in which Prof. Leslie Vosshall and I argue about human sex pheromones. I say the original concept has been stretched to fit so many variant results that it’s no longer useful. Leslie thinks otherwise.


P.S. Earlier in the program, Leslie mentioned this study showing that lap dancers make better tips during the ovulatory phase of their cycle. I agree this might be due to an airborne chemical signal but I don’t think it qualifies as a pheromone (unless tossing $5 bills at a naked girl is a behavior hardwired by evolution). Thus my otherwise baffling line: “I believe in strippers.”

P.P.S.Well, okay, maybe not that baffling.

Social Media Company Buys Itself a “Pheromone”

Somehow, I missed this press release back on May 17th:

CrowdGather Partners with Human Pheromone Sciences to Launch “Made for Social Media” Patent Pending Attraction Fragrance

CrowdGather, Inc. is a company attempting to create new value in the social media market by bundling together fan forums which, in the age of FaceBook, are considered a rather old-fashioned form of social media. Human Pheromone Sciences, Inc. has patented mood-enhancing compounds for use in perfumes and colognes, and licenses the molecules to companies such as Victoria’s Secret and Avon.

The headline was justified by this portion of the press release:

CrowdGather will partner with Human Pheromone Sciences to launch and distribute Erox®, a unisex fragrance, which has been proven to increase feelings of arousal, excitement, social warmth and friendliness in both female and male users. The fragrance will be launched, sold and marketed through the use of social media and forum communities. Erox® will be the first commercial product to contain Human Pheromone Sciences’ patent pending ER303 compound which has been shown to increase feelings of attraction and flirtiness in both males and females during a double blind placebo controlled study.

The idea of a conglomerate of online fan-sites (PaintBall Nation being one of the cooler ones; Pocketbike Planet not so much) merchandizing a flirtiness fragrance to its socially awkward base of geeks, nerds, losers, dweebs, and tech enthusiasts generated immediate mirth at Mediaite:

This Exists: ‘Social Media Fragrance’ Oddly Does Not Smell Of Cheeto Dust And Tears.

This weekend Ad Age blogger Bob Garfield joined the mockery, suggesting that one of the prime reasons for the project was “the crippling horniness of the 70% male CrowdGather crowd.”

“Our network is a sausage fest,” [CrowdGather CEO Sanjay] Sabnani says. “There’s always conversations about picking up on the opposite sex.”

[Sausage fest?—Ed.]

Being keenly interested in the business end of the perfume blotter, and having met some of the principals of Human Pheromone Sciences, Inc. [HPSI] back in the last century when it was known as EROX Corporation, my eye was drawn to the second line of the press release:

CrowdGather (OTCBB:CRWG.ob - News) today announced that it has acquired brand assets from Human Pheromone Sciences, Inc.

Hold on! There’s a world of difference between partnering with a firm and acquiring its brand assets. Exactly what assets are we talking about?

As part of the agreement CrowdGather will acquire the Erox.com domain name and trademarks from Human Pheromone Sciences, and make a strategic investment in the company via a private placement at the time a final product is accepted by CrowdGather. Human Pheromone Sciences will design and contract out the manufacture of the fragrance for CrowdGather and its distribution partners.

Hmmmm . . . With a little digging at the SEC website I found the specifics of the deal, which was consummated the day before the press release. It smells a lot more like a creeping takeover than a “partnering.” CrowdGather will provide HPSI the grand sum of $100,000. An initial $50,000 buys CrowdGather the Erox trademark and erox.com domain name, plus product development, manufacturing and fulfillment services for a CrowdGather flirtiness fragrance. Once the fragrance is launched, CrowdGather kicks in another $50,000 to acquire restricted common stock of HPSI. (This is the strategic investment or private placement part.)

HPSI stock is currently selling over-the-counter at about 11¢ per share. At that price, Crowdgather will pick up around 454,545 shares. As of its 2010 annual report, HPSI had about 4,151,954 shares of common stock outstanding. If all goes as planned, CrowdGather will own roughly 10.9% of PHS, making it the company’s second largest shareholder after HPSI director Carson Tang and the shares he owns personally and beneficially through Renovation Global Funds, L.P. (32.8% in total).

In its annual report released in March, PHS acknowledged that it “has not had sustained profitable operations,” that it “is dependent on a few major customers,” and that “it requires additional funding to continue operations.” The situation is dire: “management believes that the Company’s existing cash resources and cash forecasted by management to be generated by operations will not be sufficient to meet working capital and capital requirements through the current year,” i.e., through 2011.

So, thanks for the additional funding and welcome aboard, Mr. Sanjay Sabnani! What sort of top note did you have in mind for Eau de Geek?

Out of the Shadows: I No Longer Believe in Human Pheromones

From my earliest fascination with animal behavior in college, through my pure sensory research phase at the Monell Center, and into my mercenary research phase in the fragrance industry, the question of human sex pheromones was never far from mind. Having studied sexual behavior and smell, I eagerly read the new studies and attended the promising talks hoping to see a definitive answer emerge. Curiously, as more research was done the case for human pheromones became more tentative. Researchers I knew and respected couldn’t even agree on basic physiological facts: do humans have a vomeronasal organ or not? If it exists is it functional? If it’s functional, does it deliver a behaviorally relevant message?

I grew increasingly impatient with this state of affairs. I wasn’t the only one seeking clarity: an endless parade of associate beauty editors, science reporters, and generally intelligent people asked me whether there was anything to the idea of human sex pheromones. The best I could offer them was the lame proposition that while the molecules and the means to perceive them might still exist, the effects of human sex pheromones were unlikely to be as dramatic as those in insects or rodents. This didn’t satisfy the associate beauty editors nor did it satisfy me. Reserving judgment in the face of conflicting data is a bedrock principle of science but it doesn’t make for good sound bites.

According to the definitions first developed in the early 1960s, a sex pheromone should trigger an invariant, reflex-like behavior in most people who smell it, and it should consist chemically of (ideally) one to (at most) a small handful of specific molecules. In theory, uncorking a sample tube of male pheromone ought to make women go gaga, while a nose full of female pheromone should make men go stiff, something along the lines of the wickedly clever story by Roald Dahl called Bitch.

So, thousands of studies and millions of research dollars later, where are we?

Richard Doty, a smell researcher at the University of Pennsylvania, has now supplied the book-length answer. In The great pheromone myth, Doty provides an exhaustive—and sometimes exhausting—account of the science behind mammalian pheromones. But this is much more than a summary of 50 years worth of research—it is a thorough and relentless examination of the evolving scientific claims made for the pheromone concept itself. And it is here that Doty has provided a major contribution: nothing less than an complete take-down of human pheromones.

The great pheromone myth is an argumentative tour de force. Like a skilled prosecutor cross-examining witnesses, Doty sets the trap by quoting researchers themselves as he reviews the definition of pheromones. From one scientist to the next we find inconsistencies, contradictions, and special pleading. The cumulative effect is devastating: it demonstrates the intellectual incoherence surrounding the term. A pheromone is a simple chemical—except when it’s a blend of chemicals. A pheromone has an innate releaser effect on other animals—except when learning or context is involved. Doty also quotes those who along the way cautioned about extending the pheromone concept from insects to mammals. Like a good courtroom lawyer, he plants seeds of doubt in the minds of jurors.

Doty spells out the technical shortcomings of animal and human experiments, but he always returns to his theme: that the results rarely meet the criteria for a pheromone, even as the criteria become ever more expansive and flexible. 

As Doty dismantles one pheromone claim after another, he also builds a powerful case for the behavioral and physiological effects mediated by body odors. Mothers recognize infants, infants recognize mothers, lover recognize each other—all through natural body scent. Many of these effects involve learning and the evaluation of context, even in rats. For example, “male rats exhibit an increase in testosterone and luteinizing hormone following exposure to the wintergreen-smelling odorant, methyl salicylate, when the odor had been paired with previous copulation.” Mice raised until weaning with artificially perfumed parents later prefer to mate with similarly scented mice; mice raised unscented prefer unscented partners. These results show the importance of smell in sexual behavior and speak to learning and adaptability; but they are hard to square with the idea that mammals respond only to pheromones composed of highly specific natural body scents.

To all of which one might reply, so what? So what if there is no solid evidence in mammals that meets the narrow technical definition of pheromones? What’s wrong with calling all these various effects pheromonal?

The problem is that the pheromone concept does no intellectual work. It provides no leverage for discovering new facts or phenomena. Pheromones are the intellectual version of elastic-waisted fat pants—the concept expands to accommodate each and every claim made for it. Once upon a time instinct theory was equally in vogue and used to “explain” all sorts of behavior. Today it’s rarely invoked. By specifying the roles of context and learning, behavioral science simply outgrew the need to appeal to instinct.

Today we are seeing a new wave of research by scientists such as Denise Chen, Bettina Pause, Johan Lundström, and others showing that body odors can transmit emotional state from one person to another, and can alter brain processing and hormonal levels. It’s clear that we are much more affected by the scent of other people than previously thought. The effects are many and varied; more will doubtless be revealed. But what is gained by shoving them all under the umbrella of “pheromones”? Very little, I believe. Like Doty, I’m pessimistic the public will ever give up its fascination with pheromones, but it’s time for scientists to file them away—right next to phlogiston—in the drawer labeled “formerly useful concepts”.

The Great Pheromone Debate

By far the most contentious topic in the chemical senses is whether or not humans produce and respond to pheromones—sex pheromones in particular. That this is still a matter for debate, fifty years after the coining of the term “pheromone”, will surprise some people. Others, like myself, are simply frustrated that despite thousands of experiments and scientific publications, the issue is not yet settled.

My sense of the field is that things are changing and a resolution may be at hand. It’s something I hope to explore on FirstNerve in the coming weeks. 

To start things off, I’ve linked to this excellent mini-lecture by Dr. Tristram Wyatt, a specialist in pheromones and chemical communication in the University of Oxford’s Department of Zoology. His topic is “Success of the smelliest: Pheromones and evolution.” In twelve minutes, Wyatt puts the notion of human sexual pheromones into a clear and concise historical context. Have a look.