The Scientific Evidence: A Look at Hunter-Gatherer Studies
While anecdotal evidence might suggest a link between hunting and increased testosterone, scientific research provides a more nuanced picture. Studies observing contemporary hunter-gatherer societies offer valuable insights into the hormonal responses elicited by hunting. The findings indicate that the experience of a successful hunt can indeed cause a temporary surge in testosterone, an effect tied to both physiological and psychological factors.
The Tsimane Study: Successful Hunting and the 'Winner Effect'
A cornerstone study from 2014 examined salivary testosterone and cortisol levels in 31 Tsimane men from a subsistence population in Bolivia. The researchers took hormone samples at various points before, during, and after a single-day hunt. They found that, despite the natural daily decline in hormone levels, both testosterone and cortisol surged significantly at the time of a kill.
- The hormonal spike was also observed when successful hunters returned home with meat, suggesting a reinforcing effect related to achievement and provisioning.
- Interestingly, the researchers found that even hunters who returned with meat killed by another hunter or gathered resources experienced this hormonal boost, lending support to the 'provisioning model' of male hunting motivation. This suggests that providing for one's family, not just making the kill oneself, can be a hormonal reward.
- Critically, the increase in hormones during a successful kill was distinct from the effects of simple physical exertion. When men stalked their prey, their heart rates increased, but their physical movement, measured by an accelerometer, decreased. The hormonal surge was tied to the psychological arousal and physiological response of success, not just the physical activity.
Contrasting Findings from the !Kung San Study
Another, earlier study of !Kung San hunter-gatherers in the Kalahari desert showed different results. Over a six-day hunt, researchers observed an altered diurnal pattern of serum testosterone, with elevated evening values, but did not find a correlation between hunting success and testosterone levels. This variation highlights the complexities of human hormonal responses, which can be influenced by specific environmental factors, hunting methods, or the duration of the activity.
The Role of Psychological Arousal and the Winner Effect
The hormonal spike seen in successful Tsimane hunters is consistent with a phenomenon known as the 'winner effect.' This effect, observed in various competitive contexts—from chess to sports—is a temporary boost in testosterone and other hormones following a victory. It’s a reward-reinforcement mechanism that encourages future competitive behavior. In the context of hunting, the psychological payoff of a successful kill or returning with provisions appears to be a powerful trigger for this hormonal surge. This suggests an evolutionary link between successful resource acquisition and elevated male hormones, reinforcing the behavior that leads to providing for one's kin.
The Interplay of Testosterone and Cortisol
During a successful hunt, both testosterone and cortisol increase acutely. Cortisol is often perceived negatively as a 'stress hormone,' but in an acute, controlled context like a successful hunt, it plays a critical role in energy mobilization and focus. This differs from the negative health effects associated with chronic, long-term stress. The short-term rise in both hormones during a high-stakes event prepares the body for action, enhances muscle performance, and rewards the successful outcome.
Physical Exertion vs. The Psychological Win
It is important to distinguish between the effects of physical exertion and the psychological boost from success. Consistent, moderate exercise can lead to healthier baseline testosterone levels over the long term. However, overtraining or excessive endurance exercise without proper rest can actually increase cortisol and suppress testosterone. The unique hormonal profile of hunting combines the physiological effects of exercise with the distinct psychological reward of success, leading to a more pronounced, albeit temporary, surge in hormones like testosterone.
The Modern Hunting Context
While most modern hunting doesn't mirror the survival-level stakes of a subsistence hunter, the core psychological drivers may remain. The rush of the hunt, the stalking of prey, and the feeling of accomplishment after a successful harvest likely still trigger a similar neuroendocrine response in contemporary hunters. This suggests that the ancient biological wiring linking achievement and hormonal reward persists, even in a different cultural context.
Hormonal Response Comparison: Successful vs. Unsuccessful Hunt
| Hormone | Successful Hunt | Unsuccessful Hunt |
|---|---|---|
| Testosterone | Acute spike at time of kill and upon return; higher levels than unsuccessful hunters. | Follows natural circadian decline; potentially lower overall levels due to prolonged aerobic activity. |
| Cortisol | Acute spike, especially at the time of the kill, associated with physiological arousal. | Also follows natural circadian decline, similar to resting days. |
| Adrenaline | Likely elevated during stalking and pursuit, contributing to high heart rate and focus. | Rises during periods of pursuit, but less tied to a rewarding outcome. |
Conclusion
Successful hunting does raise testosterone, but not simply because of the physical activity involved. The increase is an acute and temporary phenomenon driven largely by psychological arousal and the rewarding 'winner effect' associated with a successful outcome. These hormonal spikes are an ancient physiological mechanism that reinforces behaviors like resource provisioning. While modern hunting differs from subsistence practices, the underlying biological responses related to challenge and success likely persist. For long-term hormonal health, consistent physical activity and proper recovery are more influential than isolated high-stakes events like a hunt.
Royal Society Publishing: Successful hunting increases testosterone
