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Love & Hate Is In The Air

Kalyn's picture

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Kalyn Schofield

Paul Grobstein

Biology 103

Web Paper#1

Love & Hate Is in the Air


            There are many ways in which a person develops feelings for another individual. We use everything from our sight to body language in an attempt to connect romantically or aggressively with someone. All of these elements play obvious influences in romantic and repulsive attraction when dealing with another individual. But how often has one every stopped to think about how the body’s natural pheromones influence these everyday relationships?

            It’s easy to overlook the important of pheromones since one cannot always see or smell them. In fact many scientists have done the very same thing and ignored the importance of human pheromones until recently. In the beginning, the study of pheromones was a subject that was only relevant when dealing with animals and insects. Many scientists both in biology and chemistry, focused on how “chemical signals” highlighted the important functions of mating rituals, group processes, and bonding within other species. By looking into the importance behind human pheromones scientists are trying to comprehend the exact role they play in altering certain human behaviors.

            In understanding pheromones and where they originated from it is helpful to think of pheromones like a community, such as a forest. A forest is a word that includes many things such as animals, trees, flowers and bacteria. Each of these components interacts with one another while still performing their own specific tasks. This is also true for the function of pheromones as pheromones also act within a community that is the human body. There are various types of bodies including male, female, child and adult. But all of these bodies produce hormones which function from within the body with the purpose of interacting with other bodies pheromones to produce a response.“Pheromones are chemicals that one individual emits to elicit responses in another individual of the same species. A pheromone provides species-specific chemical communication and elicits a neurophysiologic response that results in an alteration of sensual behavior” (Kodis & Michelle, pg 17). The word pheromone originated from the Greek language from the words pherein “I carry” and hormon “I excite.” The overall meaning of the word pheromone is “I carry excitement.”

Pheromones originate from the lipids known as steroids that are produced from within the body.  When these steroids flow to the skin they are metabolized and transformed into pheromones. Some of the most potent pheromone centers are located within the groin, armpits, skin and the nasal sulcus. The nasal sulcus is the narrow strip of skin located between the base of the nostrils and the upper lip. The production of pheromones involves the hormone known as dehydroepiandrosterone (DHEA) an important hormone that is responsible for many functions including the immune system, estrogen production in females, brain function, cholesterol reducer, antidepressant, libido enhancer and encourages bone growth. DHEA is classified as a steroid hormone that metabolizes into pheromones through the adrenal glands (located in the kidneys).  Pheromones are created from hormones which are produced by specialized cells. These pheromones enter the surrounding environment as a gas or a liquid. Heavy pheromones must be passed by physical contact and can be picked up by the tongue which passes them to the neurons in the olfactory system. This system converts their chemical messages into nerve impulses which are sent along to the brain for decoding and processing. If these behavior modifications are the direct result of pheromones what influences cause males and females to still react to them today?

Females and males differ dramatically in their production of pheromones. This is true because each gender actively produces a different ratio of estrogen, androgen and progesterone. In general, pheromones are “sexually dimorphic” meaning some are naturally more active in one sex or the other. Such an uneven distribution of pheromone production seems natural, in my opinion if one takes into account the purpose of pheromones, which is to generate a response. Why would the body generate a response or react to something in which it has adequate sources of?  By requiring various levels of pheromone production these pheromones successfully influence the behavior of the opposite sex. However, these effects are found to vary according to the sex of the individual. Pheromones live in a world that is constantly suppressing the natural body odors of humans. People repress their body odor everyday with scented products such as lotion, soap and hairspray. Yet the purpose of pheromone production is to create an effect. How can this be accomplished today in the modern world if pheromones are being suppressed? The answer is not all pheromones can be suppressed or covered up.

The steroid hormone androgen has found to be linked with aggressive behavior because it is responsible for aiding in both the development of male sex organs and characteristics. Male urine carries within it pheromones that have a steroid derivative of androgen. Similar to a dog that marks their territory, this scent yields a hostile effect when smelled unconsciously by other males. Scientist Ching-tse Lee came to the conclusion that male mice are negatively affected by other male’s urine and that a female mouse’s pregnancy will be affected by the urine as well. Such findings led me to assume that it is possible for human males and females to experience the same thing as mice. Thinking about men who come together in large groups today conjures up images of sporting events. These men are kept within an enclosed space and forced to share bathroom stalls with other spectators. A common occurrence in such situations is the creation of graffiti littered on the bath stall walls. This graffiti is usually violent, hostile, and filled with crude remarks accompanied by aggressive etch marks and sometimes pictures. Would it be such a stretch to think that there is a link between the male urine’s pheromones and such aggressive tendencies? In such a case, these males may be predisposed to act out aggressively more than they normally would. My thoughts on why this would happen have to do with the prehistoric tendency of the human species to reproduce. Men may act out aggressively when exposed to another male’s urine in order to establish dominance and dictate rank. When in the presence of another male the “alpha” male or leader would have first choice of any females within the area. By raising their aggressive levels the males would be better fit to engage in battle with another male over breeding rights. Even in society today we have a saying for such a masculine show of bravado and ego. This sort of term relates perfectly to the urinal pheromone connection and is known as a “pissing contest.”

            In understanding the effects of androstenone on women an experiment was conducted at the University of Pennsylvania. Scientist Winifred Cutler extracted sweat from male participants by requiring them to wear absorbent pads under their arms for seven consecutive days. Cutler extracted the male sweat and mixed it with alcohol. Female participants entered in the study were noted to suffer from irregular menstrual cycles. A normal cycle consists of ovulation every twenty-eight days. The women were swabbed on their upper lip with the extracted sweat for three or four months. The results indicated that the exposure to male pheromones yielded a shift from irregular to regular menstrual cycles. Another experiment with zoologist Claus Wedekind conducted an experiment using forty-nine females and forty-four males. The men were required to wear a cotton white t-shirt for two consecutive nights. To avoid contamination of their own body’s scent the men were not permitted to wear or use any fragrance, deodorant, scented soaps, lotions, drink alcohol or engage in sexual activities. The women for the experiment were in the middle of their menstrual cycles. This was an important factor because a woman’s sense of smell is thought to be the highest during this time. Each woman individually sniffed the tee-shirts of each man which were put into unmarked boxes. The women were required to rate the tee-shirt’s smell according to “sexiness,” “pleasantness” and “intensity of smell.” Results found that on average, women were attracted to odors that belonged to men who had her opposite immune system.           

            Because men have higher levels of testosterone, their sense of smell is considerably less than a woman’s. “Most women can smell mild sweat from three feet away. When they are ovulating and fertile, in mid-cycle, they have an even greater sensitivity to odors, including sweat” (Kohl, James Vaughn, and Francoeur. pg 86).” Estrogen enhances the sense of smell where as testosterone weakens it. This revelation in heightened smell for women means it is possible for women to be more sensitive to subtle pheromone cues. This would make sense and be advantageous to females. By having a stronger sense of smell females can use it to determine potential mates. By selecting a mate with dissimilar immune system, women were giving their future offspring the potential of receiving a stronger immune system. The opposing genes between mother and father would have a greater chance in yielding a stronger immune system that was less susceptible to diseases. Similar to the mice, women are also affected when in the presence of male odors. In this case the regulation of their menstrual cycle is a response in the body to remain fertile in case of sexual activity. So the stronger sense of smell serves a dual purpose of selecting a compatible mate and to regulate her body’s ovulation to keep itself at its prime in order to reproduce.

It is clear that scientific studies have found human behavior alters through the introduction of pheromones. All animals, including humans produce aromatic pheromones messengers that generate bodily reactions. There is no denying that there are a multitude of odor cues and whether or not one detects these does not change the fact that they exist. Pheromones can influence everything from bonding a child to a mother, bond soul mates or elude a harmful situation. Pheromones work together within the human body to play an active role in sexual development, physiology and behavior.

            There exists a psychology theory that could possibly back up the main function of pheromones. An American William James and Danish psychologist Carl Lange coined the theory of emotion known as “James-Lange.” This theory states that stimuli cause physiological changes in our bodies and emotions result from these psychological changes. Using this theory it is possible to entwine the effects of pheromones with their inevitable outcome of altering the behavior of an individual. The stimuli are pheromones, unconscious awakenings within the body that respond to other pheromones from other human beings. Using the example of falling in love, these could include the natural odor of a potential lover.  Once engaged, these pheromones create a response which results in a response from the body. Your eyes focus on them, you feel dizzy, your heart accelerates and you are suddenly excited. Finally, these responses generate a feeling that translates into love.

            This science of pheromones often presents humans beings as being completely swept off their feet when encountering pheromones. But people are not robots that respond the same way to any and all stimuli. But at the same time humans do not share in the automatic reactions of the animal kingdom when presented with pheromones. The inner workings of pheromones involved with humans are similar to a lock and key. Pheromones work as subtle communicators between people that create a stronger probability for positive or negative feelings. Pheromones do not provide the sole ingredient in creating instant lust or hate.

            As human beings we are bombarded by a plethora of stimuli that constantly alter our thinking and behavior. To suggest that pheromones are the main component or ultimate aphrodisiac in making a person fall in love or hate another individual is false. The conditions and circumstances all play equally important roles for any given situation and must be taken into account as well. Scientists work tirelessly to understand what makes a flawless pheromone effect. History has given us many legends of successful seductresses, sirens, Casanovas and Don Juans but little understanding as to why their methods were so successful. Could it be that the “chemistry” people talk about when referring to a loved one is really the positive interactions of pheromones? Could this also be true when a person does not instantly “click” with another? If so, one day pheromones may prove to be the tipping factor in understanding what creates positive or negative feelings between two people.



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Works Cited

Cutler, Winnifred. "Our Pheromones And Sexuality: The Current Research On Human Pheromones And Their Role In Sexual Attraction." Athena Institute mission. Athena Science. Web. 17 Oct. 2009. <>.

Gleitman, Henry, Dan Reisberg, and James Gross. Psychology, Seventh Edition. New York: W. W. Norton, 2007. Print.

Kodis, Michelle. Love scents how your natural pheromones influence your relationships, your moods, and who you love. New York: Dutton, 1998. Print.

Kohl, James Vaughn, and Robert T. Francoeur. The Scent of Eros Mysteries of Odor in Human Sexuality. New York: Authors Choice, 2002. Print.

Monde, Harvey, Lee, Ching-tse, Donovick, Peter J., Burright, and Richard G. "Male mouse urine extract effects on pheromonally mediated reproductive functions of female mice." Physiology & Behavior 20.4 (1978): 447-52. PsycINFO. Web. 5 Oct. 2009. <>.

Schulz, Stefan. The Chemistry of Pheromones and Other Semiochemicals I (Topics in Current Chemistry). New York: Springer, 2004. Print.

Small, Meredith F. "Athena Media - Scientific American features Dr. Cutler and pheromones." Athena Institute mission. Athena Media. Web. 17 Oct. 2009. <>.

"Sweaty T-Shirts and Human Mate Choice." WGBH Educational Foundation, 2001. Web. 10 Oct. 2009.





Paul Grobstein's picture

contributions of pheromones to human interactions

"Could it be that the “chemistry” people talk about when referring to a loved one is really the positive interactions of pheromones?"
An intriguing idea indeed.  But it probably ought to be coupled more explicitly with the earlier thought that "people are not robots that respond the same way to any and all stimuli."  What is it about pheromones that might make them a more interesting stimulus than what we see or hear about another person?