What is a crowd.According to the National Center for Working Conditions in Spain, the phenomenon called “collective behavior”, “mass behavior” or “collective dynamics” can be defined as all relatively spontaneous behavior carried out by a group of people before a common stimulus in an undefined or ambiguous situation. These groups of people, generally transitory and lacking formal organization, react to an immediate set of circumstances in unconventional ways. These are crowds that we could define as “a large number of people who share a common center of interest for a limited time.” Such people are normally aware of their mutual influence.
A minority decides.According to a study by the University of Leeds published a few years ago in the magazineAnimal Behaviour JournalIn human crowds, a minority of only 5% decides the way, and the remaining 95% simply follow it. “The subjects of the experiment always ended up reaching a consensus in their movements, despite the fact that they were not allowed to speak or gesture,” explained biologist Jens Krause, co-author of the research.
So we do “the wave”.Analyzing the development of fourteen “human waves” in football stadiums with capacity for more than 50,000 people, physicist Tamàs Vicsek has come to the conclusion that they generally move clockwise at a speed of 12 meters ( 20 seats) per second. And that for them to be unleashed it is necessary that at least 25 spectators raise their arms. Furthermore, the mathematical model that reproduces the movement of the wave is surprisingly similar to that which simulates the behavior of heart cells or that of the spread of forest fires.
The rules of pedestrians.French scientists from the Toulouse Animal Knowledge Research Center showed that when a pedestrian walks, they apply two rules to try to minimize congestion in their visual field:walks into the empty spaces you see and adjusts your speed to maintain a minimum safe distance from the nearest obstacle. By digitally simulating a behavior model in crowds with just these two parameters, the researchers found that the result coincided with what happens in reality, and that it explained many spontaneous phenomena, such as the formation of lines or “lanes” of pedestrians in opposite directions. , as published by the authors inPNAS.
Ants as a model.After years of observing Argentine ants (Linepithema humile), researcher Martin Burd seems to have discovered how these insects manage to control traffic in emergency situations. “When they feel panic they do not behave like humans: they remain calm, walk in orderly lines and are courteous to each other, because they do not seek the individual good but that of the group,” explains this Australian scientist.
