Pheromones a myth in mammals

Dec 02, 2010 By Mike Unger
Pheromones a myth in mammals

Something just didn’t smell right to Richard Doty. It was 1976 when the director of the Smell and Taste Center at Penn’s School of Medicine first started raising a stink about the existence of pheromones.

When his latest book, “The Great Pheromone Myth,” was released earlier this year, it reignited the debate over the science of these supposed smells.
Even the definition of the word is controversial. Generally defined as a biological chemical that induces a well-defined response in the same animal, the concept of pheromones in mammals has been around since the late 1950s.

The term has lingered in both scientific circles and pop culture since then. We’ve all heard tales of how pheromones cause sparks to fly between people who almost subconsciously follow their noses even before their hearts toward a potential sweetheart.

There’s only one problem: According to Doty, mammals (in contrast to insects), do not have pheromones.

“The pheromone term seems to have mainly attracted perfume manufacturers and people looking for the fountain of youth,” Doty says. “It’s just not the way things are. It would be like saying a particular color is why we choose a mate. That’s just not how relationships are formed.”

The fallacy of the pheromone is not a position Doty has carved out only recently. He has spent decades researching the chemical senses (smell and taste) from both basic and clinical perspectives.

“We looked at the literature relative to the set of criteria that would distinguish a pheromone from a chemical,” says Doty, a professor in the School of Medicine’s Department of Otorhinolaryngology. “In reality, almost everything you could show [illustrates] that almost all the situations of changed behavior were learned. Animals are very good at learning the meaning of chemicals.”

Doty objects to the idea that a single chemical emitted by one mammal can induce a behavioral change in another of the same species, and therefore little or no more scientific study about the cause and effect of the relationship is needed.

“It’s an oversimplification of how chemicals work in the environment and how animals are affected by them,” he says. “People have oversimplified the nature of the olfactory system. It’s the brain that interprets what meaning is. Conditioning plays a very significant role in all aspects of human and mammal behavior.”

Though it deals with a testy topic, Doty’s book generally has been received well.

“‘The Great Myth’ is a lovely mural of important developmental questions and phenomena,” reads a recent review in Developmental Psychobiology. “The book is also an excellent guide to a field of inquiry, a conceptual framework and an admirable product of scholarship. It offers much to professionals and advanced students in a wide range of sensory, behavioral, ecological, physiological and even clinical fields.”

Those who’ve criticized Doty’s book range from the militantly pro-pheromone, many of whom Doty says have stated they will not read it, to those who say the whole argument is a tussle over semantics.

“It’s erroneous to infer that all these mammalian behaviors are determined in an invariant way by a single response to a single chemical,” Doty says. “It’s not just semantics, it’s the whole conceptualization.”

Doty has spent countless hours throughout his career working to debunk myths surrounding pheromones. This book may be his crowning achievement, yet the concept seems to never dissipate.

“People want [pheromones] to exist,” he says. “It’s part of our need as humans to have belief in the unknown. We have the need to believe that certain things are happening beyond our senses.”

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superhuman
2.1 / 5 (8) Dec 02, 2010
Doty objects to the idea that a single chemical emitted by one mammal can induce a behavioral change in another of the same species


What about mammals marking their territory? There are countless examples of this behavior and it is clearly based on chemicals being left behind which then induce behavioral change in others of the same species. His objection is clearly invalid.

Now if those are not pheromones according to him then it does look like just a tussle over semantics.
Raveon
5 / 5 (5) Dec 02, 2010
I would say a pheromone is a specific sexual attractant that causes a physiological change and unconscious action. Urine is a non-specific repellent that is noticed consciously and does not usually effect a physiological change. Many chemicals can be a repellent to a single species, probably only one can be a pheromone. I never believed there was a human pheromone but there is a certain odor that attracts most males and I don't mean bacon.
Tristan_Caley
5 / 5 (9) Dec 03, 2010
Ah, yes, so when a dog is in heat and rubs itself all over my front lawn, causing my dog to go completely fucking nuts, this is because the dog in heat released absolutely nothing onto my lawn, and nothing entered my dog's nostrils causing him to hump my front gate.

Yes, this makes perfect sense now.

/s
KwasniczJ
1 / 5 (7) Dec 03, 2010
Mammals indeed have sexual attractants, too. The question is, whether to call them pheromones of not is rather arbitrary.

http://www.scienc...2514.htm
MacGuffin
5 / 5 (3) Dec 03, 2010
He's not saying mammals don't have a reaction to specific chemicals. He's saying that those reactions are a learned response, even if subconsciously.

In terms of a human male's sexual reaction to a female's odor, the idea is that it's a result the male knowing through experience that that particular odor leads to sex.
Modernmystic
3 / 5 (2) Dec 03, 2010
He's not saying mammals don't have a reaction to specific chemicals. He's saying that those reactions are a learned response, even if subconsciously.

In terms of a human male's sexual reaction to a female's odor, the idea is that it's a result the male knowing through experience that that particular odor leads to sex.


Even if true what's the practical difference?
ArcainOne
5 / 5 (6) Dec 03, 2010
Even if true what's the practical difference?


Looks to me that the practical difference is that a pheromone triggers an instinctual response, one that is not learned through social interaction. In the world of science this is an important distinction. If insects have pheromones that trigger this kind of change and mammals only respond when the chemical meaning is learned it IS a significant difference and means mammals do not have pheromones. HOWEVER, if insects respond through a learned mechanism rather than an instinctual one than that means we are dealing with the same kind of chemicals and mammals in this case DO have pheromones...

The article states pheromones are not very understood so this seems to be part of the process of refining what exactly a pheromone is. Similar to the whole Pluto not being a planet issue where we don't really have a strong definition of what IS a planet.
Raveon
5 / 5 (2) Dec 03, 2010
In terms of a human male's sexual reaction to a female's odor, the idea is that it's a result the male knowing through experience that that particular odor leads to sex


No, it just smells good and it doesn't always lead to sex.
Raveon
5 / 5 (1) Dec 03, 2010
Ah, yes, so when a dog is in heat and rubs itself all over my front lawn, causing my dog to go completely fucking nuts, this is because the dog in heat released absolutely nothing onto my lawn, and nothing entered my dog's nostrils causing him to hump my front gate.

Yes, this makes perfect sense now.

/s


You obviously don't know much about dogs.
Thrasymachus
5 / 5 (4) Dec 03, 2010
I have a problem with this:

Doty objects to the idea that a single chemical emitted by one mammal can induce a behavioral change in another of the same species, and therefore little or no more scientific study about the cause and effect of the relationship is needed.


That seems just completely wrong-headed from a science standpoint. If anything, his assertion that a smell's relationship to behavior is learned and not instinctive should provoke more study into the cause and effect relationship, not less. It also seems to me to be an enormously broad statement to claim that our most primitive sensory apparatus has no connection to any instinctive behavior. He must have a lot more than one book's worth of evidence to back that claim up.
KwasniczJ
2.3 / 5 (3) Dec 03, 2010
Pheromones are also used in the detection of oestrus in sows. Boar pheromones are sprayed into the sty, and those sows which exhibit sexual arousal are known to be currently available for breeding. In mammals, pheromones may be detected by the vomeronasal organ (VNO), or Jacobson's organ, which lies between the nose and mouth and is the first stage of the accessory olfactory system.
verminjerky
4.5 / 5 (2) Dec 03, 2010
I'm sorry but I'm not really getting it. There are, as has already been determined by the comments, smells from their own species that stimulate or provoke certain behaviors in mammals. It's also easily observable that experience (for instance, mating) isn't necessary to create a response. How else would an animal *learn* an appropriate response?

I would agree that biological odors don't necessarily cause behavioral changes in mammals, but I find it very hard to believe that they don't provoke certain appropriate responses.

I'd be less suspicious of Doty's conclusions if he weren't A. opposed to further research on the matter and B. selling something.

It sounds to me like his book really is just an argument about semantics. He sounds to me like someone denying the existence of giant semi-reptilian/avian fossilized bones because the person who discovered them called them dragons and said they breathed fire. Well, that doesn't mean there aren't bones. You know what I mean?
JVK
1 / 5 (3) Dec 03, 2010
All animals have genes and are epigenetically influenced by their social environment. Animal models explain the development of human behavior, and the animal models include insects. In social insects, social odors are epigenetic influences that allow for the development of epigenetically distinct castes (i.e., with the same genes). In mammals, the genome allows for the development of even more epigenetically influenced diversity in physiological, morphological, and behavioral differences. The influence of social odors (e.g., pheromones) on the human genome is not much different than the influence of food odors. Both are epigenetic influences that drive the molecular machineries of all organisms during their development. Dr. Doty ignores any developmental systems psychobiological approach and wants evidence that the pheromones of mammalian pheromones elicit responses that he qualifies. No wonder he can’t find evidence of mammalian pheromones.
JVK
1.8 / 5 (4) Dec 03, 2010
All animals have genes and are epigenetically influenced by their social environment. Animal models explain the development of human behavior and the animal models include insects. In social insects, social odors are epigenetic influences that allow for the development of epigenetically distinct casts (i.e, with the same genes). In mammals, the genome allows for the development of even more epigenetically influenced diversity in physiological, morphological, and behavioral differences.The influence of social odors (e.g., pheromones) on the human genome is not much different than the influence of food odors. Both are epigenetic influences that drive the molecular machinery of all organisms during their development. Dr. Doty ignores any developmental systems psychobiological approach and wants evidence that mammalian pheromones elicit responses that he qualifies. He could benefit from reading works by others.
JVK
2.6 / 5 (5) Dec 03, 2010
http://www.ncbi.n...20646176
The link is to an article on how pheromones work in a mammal, the goat. They influence an evolved neurophysiological mechanism that is common among mammals. They directly alter the "biological core" of mammalian reproduction, which just so happens to be linked to behavior. Pheromones-hormones-behavior, how is it that an olfactory researcher missed this?
upthefeels
not rated yet Dec 04, 2010
what about the perfumes made by human pheromone... there is big business of human pheromone used in perfumes..if there is no pheromone.. what about those peoples whos are in this business...
JVK
2 / 5 (4) Dec 05, 2010
With one exception, no one involved in marketing products that claim to contain human pheromones has shown that the disclosed active ingredients influence the behavior of the opposite sex. Like Dr. Doty, the marketers cannot seem to understand the levels of complexity that are involved in chemical communication among species. And species-specificity of the claimed human pheromone is a requirement. The urinous-smelling androstenone of boars is not going to have a positive effect on human females, yet this is precisely what many marketers claim. Here are two links for people who want more details. However, these journal publications are not meant to be easy reading for the masses. They are truthful award-winning reviews of the complexity involved in attempting to accurately conceptualize mammalian, including human pheromones (which Doty somehow must have missed while researching his book).
http://www.nel.ed...view.htm
http://www2.hu-be...kohl.htm
Rohitasch
3 / 5 (2) Dec 05, 2010
Hoho! Women living in close proximity with other women, like in a hostel or sharing a flat, get their menstrual cycles synced by learning according to Dr. Doty, I presume. I guess the alpha female would be saying,"Hold it in,...Hold it in,...Now release!" and pow - they all get their periods! Lol!
JVK
2.6 / 5 (5) Dec 05, 2010
RE: synchronous cycles. My first presentation to a scientific congress was Luteinizing Hormone (LH) the link between sex and the sense of smell? The question mark indicated that I was speculating (in 1992). Since then both the androstenol-containing axillary secretions of men, and androstenol itself have been shown to increase levels of LH, which is a well-known hormonal indicator of reproductive fitness. LH levels also are associated with properly timed reproductive sexual behavior in mammals. Let me reiterate: Pheromones-hormones-behavior, how is it that an olfactory researcher missed this? And how is it that others who are supposedly in the know about such things have written favorable reviews of Doty's book?
jmcanoy1860
not rated yet Dec 07, 2010
Ah, yes, so when a dog is in heat and rubs itself all over my front lawn, causing my dog to go completely fucking nuts, this is because the dog in heat released absolutely nothing onto my lawn, and nothing entered my dog's nostrils causing him to hump my front gate.

Yes, this makes perfect sense now.

/s


As our illustrious colleague above has indicated there is a rather extreme departure from normal doggie societal norms whilst in estrus. I myself had a even tempered "pitt-bull" when I was younger which at certain times of the year would literally chew through a solid oak gate in the matter of 6 hours to get at the poon. This is NOT learned behavior.

Similarly DO NOT wear deer attractant. You might find yourself being viciously sodomized by it's antler wearing courtier. Also, this is not a learned behavior and it has decidedly negative survival benefit.
jmcanoy1860
5 / 5 (1) Dec 07, 2010
Hoho! Women living in close proximity with other women, like in a hostel or sharing a flat, get their menstrual cycles synced by learning according to Dr. Doty, I presume. I guess the alpha female would be saying,"Hold it in,...Hold it in,...Now release!" and pow - they all get their periods! Lol!


Perhaps they learned to "rag it" together as claimed by the author.
JVK
2 / 5 (4) Dec 08, 2010
Re: Deer attractant

I am reminded of a reported incident from:
Gibbons, D.L. (1989) Unusual case: Sex in the woods. Medical Aspects of Human Sexuality, 23,10(Oct):63.

“Cindy, who was menstruating… had gone alone to a portable commode hidden in a thicket to change her tampon, unaware that a young stag was nearby… Smelling her menstrual secretions, the deer became sexually aroused. He bounded through the trees and knocked Cindy to the ground. Then while prancing up and down with his forefoot on her shoulder, the sexually excited deer sprinkled her with semen.”

The existence of mammalian pheromones is no joking matter, but this incident does give new meaning to the phrase “terms of endeerment.” The involvement of mammalian pheromones in sexual arousal should not be underestimated, much less negated by Dr. Doty’s opinions about olfactory/pheromonal or visual appeal.