For millennia, humanity had used a simple trick to walk without being stamped with the elements: look ahead. This old maxim has passed away in recent years. The popularization of smartphones has filled the streets with people absorbed in their screens, wandering through cities without paying much attention to their surroundings. None of us are absolved of sin. You have been one of those people; I have been; we all have been.

What if. That has made us the worst. Even science knows.

Knowledge . Given that there is no area of ​​knowledge that science has not investigated to its ultimate consequences, the number of works devoted to the way we walk down the street, or rather, to how thousands of individuals synchronize their movements subconsciously to facilitate step of one and the other, it is quite high. There are two major hypotheses : on the one hand, “mutual anticipation”; on the other, the “alignment” with the fastest leaders of the group.

How it works. The first theory points to a series of subconscious decisions and non-verbal communication. As we walk down the street, we anticipate the movements of the rest of the pedestrians ( fleeting glances, body clues) and we adapt our path to avoid the collision (those small seconds of impás in which we choose to move to the left or to the right). We do it constantly and in unison, which facilitates a fluid movement, in a kind of collective intelligence.

The second, developed in a little more detail in this study , speaks of “attraction.” When we walk in groups we tend to locate the fastest individuals and adapt to their pace and direction. We are looking for leaders to break through the crowd. It is an idea that has also spread to the animal kingdom , an alignment of rhythm. Other works have explained both mechanisms under the idea of ​​a “repulsive force”, in the electrostatic way, which prompts us to change direction when we get too close to someone (avoiding contact).

The problem. But what happens to this refined mechanism when we introduce the variable “smartphone“? This is what a group of experts from the University of Tokyo wanted to find out. Their results, collected in this research, are illustrative. The work experimented at street level with 27 volunteers. Half of them received yellow hats; the other half red. The authors simulated various situations in which both groups were face to face and recorded their behavior in an overhead shot to see how they solved each problem.

No leader . When neither of the participants looked at their mobile phone while walking, the two groups behaved in the expected way: the people in front of each one of them, the leaders, chose different paths to overcome the human obstacles and the rest of the group companions followed. your steps. Anticipation, attraction, alignment, and so on. The key here lies in the leaders . When we enter a large crowd (concert) someone takes the lead and opens the way; the others follow.

“I try to predict where you will be in the future and you try to predict where I will be in the future,” explains one of the authors in Wired, “and that mechanism is what allows us to have this type of collective training.” It happens that this whole system goes to waste when that leader has walks looking at his screen. Attentive to other questions, our reading of the situation disappears. Instead of looking for an efficient way to the end of the agglomeration, we wander through the mass.

Breaking everything . This makes us more prone to collision, misleading the companions who walk in our direction tied to our wake. This is when the collective choreography breaks down and an erratic dance begins: people attentive to their surroundings try to predict our movements, but when we are looking at the mobile we are not able to calculate theirs. Confusion, contact, anger. Thousands of years of nonverbal reading and fine subconscious analysis flushed down the toilet.

The rhythms. The work is interesting because it sheds light on the dynamics that backbone the daily hustle and bustle of the masses, both in large cities and at mass events such as the hajj. A bustle that is not monotone and that changes depending on the culture of each country or large city: we know that not everywhere you walk at the same speed and that collective movement patterns (the label by which we read each other to the others on the street) are different in Singapore or Paris. All of them have something in common: those who look at the cell phone break everything.

Image: University of Tokyo