The sight of meat, such as a juicy roasted turkey on the Thanksgiving table, may promote caveman behavioral traits, according to new research recently presented at a McGill University undergraduate science symposium.
The study adds to the growing body of research on priming and aggression, which holds that looking at an object possibly learned to be associated with aggression, such as a gun, can make someone more likely to behave a certain way.
"I theorized that meat would elicit an aggressive response because it would be beneficial to our ancestor's adaptation in that it would place our ancestors in a state optimal for hunting and co-opting meat resources, where aggression would be necessary," project leader Frank Kachanoff told Discovery News.
"Fruits and vegetables would probably not require as much aggressive force to be acquired," added Kachanoff, a McGill Department of Psychology researcher.
For the study, subjects had to punish a script reader every time he made an error while sorting photos. Some of the images showed cooked poultry and red meat, while others displayed geometric shapes. The subjects believed they could inflict various volumes of sound, ranging from barely noticeable to "very painful" to the script reader, which he would hear after his performance.
The script reader was actually a colleague of Kachanoff's who never endured the punishment and who feigned forgetting his lines every so often, looking at a cheat sheet for six seconds each time he "forgot" his script.
The researchers predicted that when pictures of meat were sorted, as opposed to geometric shapes, participants would inflict more discomfort on the reader. Just the opposite happened, however. The meat images actually resulted in less punishment.
"It would make sense that our ancestors would be calm, as they would be surrounded by friends and family at meal time," Kachanoff said.
"It would have been favorable to our ancestors' fitness, if they would become less aggressive after hunting was completed, when he or she was around relatives sharing food," he further explained. "This would decrease the chance of one harming a relative with whom much of their DNA is shared."
Evolutionary psychologists believe it is useful to look at innate reflexes in order to better understand societal trends and personal behavior. Such studies often look at ways society may influence environmental factors in order to decrease the likelihood of aggressive behavior.
Researchers at Munich's Ludwig-Maximilian University and the Allianz Center for Technology, for example, studied whether playing virtual racing games was linked to risk-taking behaviors.
They found that those who play more virtual car-racing games were more likely to report that they drive aggressively and get in accidents. Less frequent virtual racing was associated with more cautious driving.
"Playing racing games could provoke unsafe driving. ... Practitioners in the field of road traffic safety should bear in mind the possibility that racing games indeed make road traffic less safe, not least because game players are mostly young adults, acknowledged as the highest accident-race group," the team wrote in a Journal of Experimental Psychology: Applied study.
In the future, Kachanoff plans to rework his meat experiment by showing participants pictures of live animals most likely to have been hunted by our ancestors.
"Also, it would be interesting to have a condition in which the animal's carcass would be shown," he said. "I would predict that these conditions would elicit an aggressive response in participants relative to neutral stimuli."