Geschatte leestijd: 4 minutenResearch on mice shows that evolution can develop the body to be geared towards fleeing or fighting. Mice inclined to flee also turn out to be better runners.
Fleeing or Fighting
When I used to teach at gyms in Kobudo, I often explained the importance of a good fight-or-flight instinct when your life is in danger. “‘Channeling your inner Mike Tyson or Carl Lewis’, as long as you do something.” Those references, of course, mean nothing to the average 16-year-old, so I often continued: “rendering the other harmless in ten seconds or being 100 meters away in 10 seconds. The most important thing was to prevent a third, typically human, reaction to danger: freezing. Because we are so accustomed to a society in which others are responsible for our safety, responding to danger becomes increasingly unnatural. Meanwhile, some of these instincts seem to be returning now that attacks are more frequent. In other threatening situations, many people waste too much time wondering to themselves, “Is this really happening? Do I really have to take care of my own safety now?”
Fortunately, this does not yet apply to mice. They still instinctively react to any form of danger by fleeing or fighting. However, this reaction does not seem to be entirely based on considerations made at the moment of danger. The bodies of the fleeing mice appear to be more effective at running than the bodies of the fighters, who consume more energy in a short time. So, the body of the fleeing mouse also seems better built for fleeing.
The University of Utah conducted research on how male mice defend a territory with female mice against other males. They were housed in a lab with enough space for the runners to retreat. In addition, the researchers measured the effectiveness with which the males ran on a treadmill.
The mice inclined to flee were found to consume less energy (oxygen) while running and could (in theory) therefore run longer than the fighters. The fight-or-flight response thus turned out to be linked to the degree to which the body is suited for fleeing or fighting. The ‘fighter mice’ burned more energy relative to their mass.
‘More Efficient Running’
This difference in reaction was also unrelated to body composition. The fleeing mice were not smaller in size than the fighting mice. No other differences such as muscle fiber distribution and factors like testosterone were examined.
When looking at the difference in muscle fibers, fighters are normally benefited by the fast-twitch fibers that provide explosive power, while marathon runners rely on the slower-twitch fibers that can provide energy for longer durations. On the other hand, those fast-twitch fibers are necessary to sprint away from a pursuing tiger. If you have proportionally more fast-twitch fibers, you rely more on the system that provides a lot of energy in the first ten seconds without using oxygen. The research looked at the amount of oxygen consumed. If you use proportionally less oxygen, you can theoretically run longer, but not necessarily faster. In nature, we also see that some animals rely on sprinting ability to flee or hunt while others are more built for endurance. So, I wonder if oxygen consumption can be seen as a better flight mechanism. Moreover, I can imagine that there are significant differences in this regard between different life forms and their place in the food chain.
From Fleeing to Fighting
The researchers take into account that a similar relationship applies to humans since they also have the fight-or-flight instinct. However, as far as I’m concerned, the above research does not necessarily mean that you cannot influence this relationship if it already exists. You can decide to become even better at your instinctive reaction and as a ‘fleeer’, for example, engage in a lot of running and other endurance sports. You can also decide to work on ‘weak’ points instead.
Few would prefer to call themselves a ‘fleeer’ rather than a fighter. By nature, I tend to flee rather than fight. I am not inclined to seek confrontations and consider myself a pacifist. And yes, I was the best runner in the class by nature. However, this is my natural instinct, it doesn’t mean I act upon it. Although looking back, I’m still glad I walked away in certain situations, I always regretted it when it didn’t feel like a rational choice. It was a reaction to an instinctive feeling of self-preservation, more of a physical reaction than a mental one.
Five years, 20 kilograms of muscle mass, and the necessary dan degrees in Eastern martial arts later, I felt like a fighter. In the few ‘potentially physical’ confrontations that followed, I walked away again. However, this time I had to drag myself away, knowing that it was wiser not to leave the other crawling (or to be surprised with a weapon). That felt a lot better. I don’t want to be a ‘fleeer’ or a ‘fighter’, but just a rational thinking human with the physical and mental potential for both.
So, I can recommend those fleeing mice to find a good gym and dojo. On the other hand, you can wonder how much that yields if you throw a cat into the lab.
References
- Jeremy S. Morris, James S. Ruff, Wayne K. Potts, David R. Carrier. A disparity between locomotor economy and territory-holding ability in male house mice. The Journal of Experimental Biology, 2017; 220 (14): 2521 DOI: 10.1242/jeb.154823
