People are more likely to snack faster when someone else is around because people are wired with a ‘foraging mindset’
- People snack more often on small portions in the presence of food rivals
- Social animals adapt to signs of food competition – and humans are no different
- The behavior can be an evolutionary trait to prevent our food from being shortened
The presence of someone else while eating makes us switch to a “ foraging tactic ” that makes us eat more regularly for small portions, scientists say.
Japanese experiments showed that even when there was no real competition for food, people in pairs achieved smaller portions of chips, but more often.
This compared to study participants who were alone and who less often took larger portions of chips.
The research team compared the results with groups of mammals and birds that automatically eat small portions faster in the presence of a “food rival.”
Such a change in behavior in nature can be a built-in tactic to reduce the risk of some of their portion being stolen by nearby shooters
The researchers provided the subjects with a plate of chips and compared their foraging behavior solo and in pairs
Humans and other animals may have a built-in system that automatically causes the shift in the presence of others.
“Our results showed that the behavioral change was caused by the presence of a co-eater, even without competition,” the researchers write. Royal Society Open Science.
“This suggests that the underlying mechanism for the shift may be a built-in system that activates automatically in response to relevant social signals.”
To test whether a shift in eating behavior would be caused in humans, study participants were asked to do a lab test alone or in pairs.
They recorded the frequency with which the participants reached for chips, the weight of chips per range and the total amount consumed.
An electronic balance, invisible to subjects, was placed under the plates to record the timing and weight of the chips at each range.
Paired subjects (left) sat at opposite corners of a table, each with their own chip board, while in the solo condition (right) a contestant ate alone. Someone else on the other side of the table affected eating behavior even though it was clear they had their own portion
The scales under the plate recorded how often participants took a serving – and how large their serving sizes were
Subjects were also instructed not to eat two hours before the experiments to ensure consistent hunger levels.
Although the other subject had their own plate of chips, smaller subjects more often looked for smaller amounts of food.
However, total food intake did not increase in the ‘paired’ settings compared to the solo condition.
The research team conducted separate experiments for men and women, following the results of a preliminary questionnaire that showed that women were more concerned about the amount of meals than men.
Certainly, the frequency and total food intake were higher in men than in women, they found.
Previous research with crows has shown that smaller foods are less likely to ‘grill’ than larger foods
Social foraging – the search for food in groups – in the wild offers several benefits to animals, including greater chance of encountering food and collective monitoring of potential predators while eating.
However, it can also create competition between co-foragers, as individuals can ‘participate’ in others’ successful search efforts and steal bits.
The tactic of picking up small pieces more often than smaller pieces less often reduces the risk of shock from other individuals.
A previous study found chicks were approached and pecked more often with food when a co-forager was present, compared to when they were isolated.
Another study with crows discovered that smaller foods are less likely to be scraped than larger foods.