(C) Live Science

A recent study published in the international academic journal, Evolution and Human Behavior, suggests a direct, albeit subtle, link between male testosterone levels and how their body odor is perceived by others. Men with higher circulating levels of the male sex hormone testosterone consistently emitted a scent that was interpreted by others as being "more dominant" or "authoritative" compared to men with lower levels. This groundbreaking research from a collaborative team of Canadian and British scientists provides new insights into the role of chemical communication in human social status and perception. 

Unpacking the Study: Methodology and Key Findings 

The research was designed to isolate the potential influence of body odor on social perception. The study involved:

Measuring Testosterone: Seventy-four healthy adult men had their testosterone levels accurately measured. Testosterone is primarily responsible for the development of male secondary sexual characteristics and plays a significant role in metabolism and behavior.
Odor Collection: These men were instructed to wear a plain cotton T-shirt for a specific period to allow their unique body odor to impregnate the fabric.
Oception and Evaluation: A large group of 797 male and female participants were then asked to smell the worn T-shirts. Crucially, they were asked to evaluate the impression of the person who wore the shirt across several social traits, including dominance, aggression, attractiveness, and friendliness.
The results were compelling: the body odor from men with higher testosterone concentrations was uniformly perceived as more dominant or authoritative than the scent of men with lower concentrations.

No Gender Difference in Perception 

An unexpected finding was the lack of a sex-specific effect. The researchers had initially hypothesized that women, often noted for superior olfactory abilities, might exhibit a stronger response, particularly one linked to mating or partner choice. However, the effect of high-testosterone odor signaling dominance was observed equally across both male and female evaluators. This suggests that the olfactory cue serves as a general social signal rather than a specific mating signal. 

Evolutionary Psychology: Dominance vs. Prestige 

The study’s findings are particularly relevant when viewed through the lens of evolutionary psychology, which differentiates two primary strategies for achieving high social status: Dominance and Prestige.

Dominance Strategy: This is a status strategy achieved through threat, physical strength, coercion, or intimidation to gain resources or compliance from others. This status is often associated with aggressive posture and a lower vocal tone.
Prestige Strategy: This is a voluntary form of respect and deference granted to individuals who possess superior skills, knowledge, wisdom, or technical expertise. This status is associated with confidence and strong social connections.
The study's most interesting nuance lies in the distinction between these two status markers and the observed biological signal:

Testosterone and Dominance: The research established a clear connection between higher testosterone and the olfactory perception of Dominance. The body odor acts as a biological signature, a subtle social cue, that non-verbally communicates a disposition toward this status strategy.
Testosterone and Prestige: Conversely, the study found no correlation whatsoever between testosterone levels and the perceived Prestige of the odor.
The researchers explained this disparity by noting that Prestige is a status strategy heavily influenced by cultural factors and is typically expressed through social behaviors (e.g., teaching, advising, leading by example) rather than raw biological signals like body chemistry. 

A Subtle Signal, Not a Determinate Trait 

It is crucial to note the researchers' caution: being perceived as 'dominant' through scent does not necessarily mean the individual is actually dominant or aggressive in their personality or behavior. The effect observed in the study is described as small and subtle.

The human sense of smell, or olfactory system, is capable of detecting incredibly minute chemical differences in an individual's chemisignals (chemical signals that carry social information). The body odor, primarily produced by the apocrine glands and metabolized by skin bacteria, contains volatile organic compounds (VOCs) that reflect an individual's hormonal state and genetic makeup.

While the study confirms that these chemical signals influence how people judge dominance, the researchers strongly emphasized that in daily life, the effect of body odor is eclipsed by overt social signals such as posture, verbal communication, facial expressions, and demonstrated social competence. 

Future Directions: Expanding the Chemical Dialogue 

This research contributes significantly to the growing field of chemical communication in humans, reinforcing the idea that we are not entirely visual or auditory beings in our social interactions. The findings suggest that body odor acts as an honest, unconscious signal of a man’s hormonal profile, specifically concerning traits associated with a dominance-based status strategy.

Future studies will likely focus on:

Identifying the specific VOCs responsible for the "dominant" scent to understand the precise chemical mechanism.
Investigating the effects of stress and short-term hormonal fluctuations on this olfactory signal.
Examining cross-cultural variability to see if the perception of this dominance signal is universal or culturally modulated.
The "scent of power," while a subtle whisper in the cacophony of social interaction, provides a fascinating glimpse into the deep, often unseen biological underpinnings of how humans perceive and navigate the complex hierarchies of status.